ky thuat bao quan che bien qua

7/27/2019 Ky Thuat Bao Quan Che Bien Qua

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Sha bi Trung tm Hc liui hc Thi Nguyn http://www.Lrc-tnu.edu.vn


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S ha bi Trung tm Hc liu i hc Thi Nguyn http://www.Lrc-tnu.edu.vn 1

K THUT S CHBO QUN QU


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Cc ch vit tt v ch gii

BQ BQBVTV BVTVCA Control Atmosphere (Kh quyn kim sot)C C

GAP Good Agricultural Practic (H thng thc hnh nngnghip tt)

MA Modified Atmosphere (Kh quyn iu bin)MAP Modified Atmosphere Packaging (Bao gi kh quyn

iu bin)

SCBQ S ch BQTC TCTCN TCNTCVN TCVNVSATTP VSATTPVSV VSV


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M u

Cun sch K thut s ch bo qun (SCBQ) qu ra i nhm p ngi hi ngy cng cao v k thut SCBQ qu ca cn b khuyn nng cc cp.Cun sch c bin son trn c s cc ti liu tham kho cp nht trong,ngoi nc v tng kt nhng kinh nghim thc tin cc a phng nc ta.

i tng s dng cun sch l cc cn b khuyn nng cp tnh v huyn.

Ni dung sch gm:

Phn 1: Khi nim c bn lin quan n SCBQ v phng php bo qun(BQ) qu.

Phn 2: cng bi ging v SCBQ qu.

phn 1 ngoi cc khi nim c bn lin quan n SCBQ qu, chng tia ra k thut BQ c th cho 7loi qu ph bin Vit Nam bao gm: chui,da, mn, qu c mi, thanh long, vi, xoi. Cn b khu yn nng c th lachn nhng itng qu ph bin a phng ging dy. Phn 2 cacun sch l cng bi ging v SCBQ qu, trong phn k hoch bi

ging chng ti a ra thi gian cn thit cho mi chuyn . Khi p dng voging dy, thi gian ny c th thay i cho phhp vi tnh hnh thc t calp hc.

Cun sch l thnh qu ca s hp tc gia Trung tm Khuyn nng Qucgia v Vin C in Nng nghip v Cng ngh sau thu hoch.

Do nhiu nguyn nhn khch quan v ch quan, chc chn cun sch vncn nhiu hn ch. Trung tm Khuyn nng Quc gia xin trn trng gii thiucun sch ny v mong nhn c nhng kin ng gp ca bn c.

Trung tm Khuyn nng Khuyn NgQuc gia


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PHN 1. KHI NIM C BN LIN QUAN NSCBQ V PHNG PHP BO QUN QU

1. Qu trnh xy ra trong SCBQ qu ti

1. c im qu ti

Qu ti l mt loi nng sn tng i kh BQ v hm lng nc trongqu cao, l mi trng tt cho VSV hot ng. Mt khc thnh phn dinhdng trong qu ti phong ph, c cha nhiu loi ng, m, mui khong,vitamin, kt cu t chc t bo ca a s cc loi qu li lng lo, mm xp,d b sy st, st m, bp, nt nn d b VSV xm nhp.

Trong qu ti cn cha nhiu loi men, sau khi thu hoch trong qu trnhBQ vn din ra hng lot cc qu trnh sinh l, sinh ha trong ni b, lm tin cho VSV pht trin.

Trong qu trnh tn tr qu ti, cc bin i v vt l , sinh l v sinh haxy ra c lin h cht ch v ph thuc vo tnh cht t nhin ca qu ti:ging loi, iu kin trng trt v chm sc, C thu hi, k thut thu hi, vnchuyn v nhng yu t k thut trong qu trnh tn tr.

Phn ln cc bin i ca rau qu sau thu hoch l tip tc cc bin itrong qu trnh pht trin ca chng. Cc bin i sau thu hoch l s phn hyv tiu hao vt cht sinh nng lng duy tr qu trnh sng khc c bn cc

bin i trong pht trin l s tng hp cc cht.

2. Qu trnh vt l

1. S bay hi nc

Khi BQ, qu b mt nc i lin vi mt khi lng v gim phm cht, mts hp dn, ho, mm, nhn do nc trong cc t bo qu b bc hi. bc

hi ph thuc vo loi, C v tit din ring ca mi loi qu cng nh ccyu t mi trng BQ (nhit , m , ). Qu c v mng bc hi nhanhhn qu c v dy hoc v cng, qu nh bc hi nhanh hn qu to. Khi qu

bc hi, nu khng c thng thong th nc ngng t trn b mt qu vbao b to iu kin cho VSV pht trin lm cho qu mau hng.


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Trong thc t BQ, gim s bay hi nc ca qu ti, thng p dngcc bin php sau: h thp nhit , tng m v gim tc chuyn ngca khng kh trong kho BQ. Ngoi ra cn dng cch xp qu ti trong hmt, vi trong ct, ng trong ti plastic, gi trong giy hoc bc trong spTuy nhin, cc bin php ny c th lm nh hng n h hp ca qu. Hhp ym kh, m cao mc nht nh li l nguyn nhn gy h hngcho qu ti: t bo qu b cht, vi khun gy thi v nm mc d dng phttrin.

Do vy, khi BQ tngth qu cn nghin cu nhng iu kin BQ thch hpv cn c thm bin php chng thi, mc .

2. S gim khi lng t nhin

S gim khi lng t nhin l s gim khi lng ca qu ti do bay hinc v tn hao cc cht hu c trong khi h hp. Trong bt c iu kin tntr no khng th trnh khi s gim khi lng t nhin, tuy nhin khi toc iu kin tn tr ti u th c th gim n ti thiu. Khi lng qu gimi trong thi gian tn tr ny ph thuc vo nhiu yu t: ging loi, vng khhu, cch thc chm sc bn phn, ma v v cng ngh tn tr, mc nguyn vn cng nh C ca chng,

3. S sinh nhit

Tt c nhit lng sinh ra trong qu ti khi tn tr l do h hp. Hai phnba nhit lng ny ta ra mi trng xung quanh; cn mt phn ba c dngvo cc qu trnh trao i cht bn trong t bo, qu trnh bay hi v mt phnd tr dng nng lng ha hc. Bit c cng h hp v nhit tntr, c th tnh c lng nhit ta ra, lng xy cn thit v lng nc sinhra. Nhng s liu ny cn thit cho tnh ton cc trang thit b trong kho BQ.Trong tn tr qu ti cn duy tr cc thng s nhit , m ti u trongkho. Khi nhit tng s kch thch cng h hp mnh ln. Khi nhit v m tng ln n mc thch hp cho s pht trin vi khun v nm mc thnhit lng sinh ra li tng hn na, mt mt do h hp ca qu, mt mt do h

hp ca VSV. l iu kin dn n h hng qu nhanh chng.

3. Qu trnh sinh ha

1. S thay i thnh phn hahc


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Gluxit lun l thnh phn c thay i ln v mnh nht trong khi tn trcng nh trong qu trnh sinh trng pht trin ca qu ti.

Trong nhiu loi qu c h hp t bin th s bin i tinh bt thnh ngl mt c trng. Hm lng tinh bt gim do qu trnh ng ha, di tc

dng ca cc enzim ni ti m ch yu l ba loi phosphorilaza. Tng lngng khi tng ln v n khi t cc i nht nh li gim xung.

S tch t ng trong thi k chn khng ch do ng ha tinh bt m cndo s thy phn hemixenluloza. Khi b thy phn hemixenluloza to thnh ccng xiloza, manoza, galactoza v arabinoza (cc pentoza), v cu trc t bo

b ph hy.

Cht pectin cha mt phn ba cht kh ca thnh t bo s cp ca tri cy.Trong qu trnh chn, protopectin chuyn thnh pectin ha tan, lm cho lin kt

gia cc t bo v gia cc m b yu i lm cho qu b mm. Khi qu chn, cccht pectin b phn hy n axit pectic v metanol lm cho qu b nhn v cutrc b ph hy. Nhng i vi mt s qu hch c th thy hin tng ngcli l lng protopectin tng ln trong qu trnh chn d tng lng pectin gimv ch khi qu chn lng protopectin mi gim i.

Hm lng xenluloza trong tri cy hu nh khngthay i.

S st gim axit l do tham gia vo qu trnh h hp v decacboxyl ha. Khi cc axit hu c (v d axit malic) b phn hy n CO2 v CH3CHO

(axetandehit). Tng cc axit hu c trong qu gim i, tuy nhin tng loi axitc th tng lndo nhng nguyn nhn khc nhau. Hm lng axit gim cngvi s gim lng tinh bt v s tng lng ng lm tng tr s pH v tngv ngt ca qu.

Cc cht mu thay i r nht trong qu trnh chn. Thng thngchlorophyll dn dn gim i trong khi carotene dn dn tng ln tr thnhcht mu chnh ca qu chn. Tuy nhin, trong chui tiu, caroten khng itrong qu trnh chn; cn trong cam, caroten bt u tng dn khi trn v khngcn mu xanh.

Hm lng tanin gim i trong qutrnh chn v gim ngy cng nhanh,lm thay i v (v cht) ca qu.

Hng thm c sn sinh do cc cht bay hi c tng hp trong qutrnh chn ca qu v gm c cc andehit, ru, este, lacton, tecpen v hp chtlu hunh.


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Vitamin C gim mnh trong qu trnh tn tr, c bit l vi cc loi qukhng tn tr c lu. Trong qu trnh chn, vitamin C ca qu gim i nhanhhn do cc qu trnh kh trong cc m b ph hy v khng kh xm nhp.

Mc ch qu trnh BQ l duy tr chtlng dinh dng ca qu, v vy cn

gi qu trong cc iu kin tn tr ti u hn ch s bin i cc thnh phnha hc dn n s suy gim cht lng v h hng qu.

2. H hp

1. Qu trnh h hp

H hp l mt qu trnh m cc vt cht hu c (carbonhydrate, protein,lipit) chuyn ha thnh cc hp cht cui cng n gin hn v gii phng

nng lng. Trong qu trnh h hp, kh O2c s dng, kh CO2v ncthi ra. Chnh v vy cng h hp lin quan mc tn tht, thi hng snphm sau thu hach

H hp l chui cc phn ng sinh ha cung cp nng lng cho t bo.Cng h hp l ch tiu nh gi mc trao i cht ca rau qu.

H hp c th coi l mt qu trnh t xc tc. Nc v nhit do h hp gyra lm qu trnh h hp mnh lit hn, c nh vy cho n khi rau qu hnghon ton.

H hp l qu trnh sinh hc c bn xy ra trong rau qu khi BQ ti, l qutrnh xy ha chm cc cht hu c phc tp di tc dng ca enzim cc chtny phn hy thnh cht n gin hn v gii phng nng lng.

Trong qu trnh h hp, di tc dng ca enzim, cc cht dinh dng b xy ha thnh CO2 v H2O .

Trong qu trnh h hp, mt lot nhng bin i trung gian ca cc cht sxy ra vi s tham gia cahng lot nhng enzim. H hp thc vt khc hn

vi h hp ng vt v trong iu kin c xy hay khng c xy, thc vt vnh hp c .

2. Cng h hp

xc nh mc h hp mnh hay yu ca tri cy trong thi gian BQngi ta dng khi nim cng h hp. Cng h hp c xc nh l


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lng O2tiu th hoc lng CO2thot ra ca 1 kg qu trong 1 gi mt nhit xc nh (mgCO2/kg.h hoc mgO2/kg.h). Cng h hp ca mi loi qu

ph thuc vo bn thn qu (ging loi, C, mc nguyn vn) v cc yut ca mi trng (nhit , m, s thng gi, thi gian BQ, nh sng)

3. Phn loi h hp

Da vo bn cht qu trnh h hp ngi ta phn chia thnh cc loi h hpsau:

H hp t bin

Trong qu trnh chn ca qu, c s bin i rt r rt v cng h hpca qu m c trng l s tng nhanh cng h hp v sau li gimnhanh to nn mt nh h hp gi l s h hp t bin. im t bin nh ldu hiu s bt u ca cui qu trnh sng ca qu mc t bo v cng lmi quan tm c bit ca cc nh nghin cu sinh hc v ngi tiu dng.nh t bin cao hay thp ph thuc vo loi ging ca qu.

Thng thng, qu giai an chn n c hoc mm sau nh t bin.c tnh ca qu l thu hi qu lc cha chn sinh l, qu vn chn n c. Vvy, i vi qu c t bin h hp, thu hi qu khi qu xanh gi s BQ clu hn m khng nh hng n cht lng n ung v qu vn c th tip tcchn c sau khi hi khi cy trong qu trnh BQ. Mt s loi qu h hp t

bin nh: chui, u , xoi, i, mng ct, su ring, o, mn, chm chm

H hp khng t bin

Khc vi h hp t bin, h hp khng t bin l cng h hp thp vgim dn rt chm trong qu trnh chn nc theo thi gian. c tnh caqu l thu hi qu lc cha chn sinh l, qu s khng chn n c. V vy, ivi qu khng h hp t bin, khng c thu hi qu khi qu cha chn nc v qu khng th tip tc chn c sau khi hi khi cy trong qu trnhBQ.

Mt s loi qu h hp khng t bin nh: nhn, vi, da, bi, cam,chanh, qut, nho, kh,

Theo bn cht ha hc ca qu trnh h hp c:

H hp hiu kh


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Qu trnh h hp c y xy gi l h hp hiu kh, theo phng trnhsau:

C6H12O6 + 6 O2 6 CO2 + 6 H2O + 2816 KJ (hoc 674 Kcal)

Khi h hp hiu kh, to ra sn phm cui cng l CO2, H2O v nhit, cmt phn t gam ng hexoza sinh ra 674 kcal, lm bc nng khi nguynliu trong kho tn tr. Nu khng lm thng thong y th s sinh nhit nys kch thch tr li, lm tng cng h hp, tch t thm hi nc. Nhit v m tng cao cn l nguyn nhn thc y s hot ng ca nhiu vikhun v nm mc gy h hng nguyn liu BQ.

H hp ym kh

Qu trnh h hp din ra trong iu kin hm lng xy trong khng kh

thng nh hn 2% gi l h hp ym kh, ng b ln men theo phng trnhsau:

C6H12O6 2 C2H5OH + 2 CO2 + 117,23 kJ (28 Kcal)Khi h hp ym kh, to ra sn phm cui cng l CO2, ethanol v nhit.

Lng nhit sinh ra t mt phn t gam hexoza do h hp ym kh s t hn 24ln khi h hp hiu kh. Cho nn m bo nhit lng duy tr qu trnh sng,khi h hp ym kh s tiu hao mt lng cht dtr ln hn nhiu ln so vih hp hiu kh, v vy s gim khi lng t nhin c th t nhng cht kh li

tiu hao nhiu. Trong qu trnh BQ qu ti, cc t bo dn dn mt kh nnghp thu oxy v dn dn chuyn qua h hp ym kh, tch t cc hp cht trunggian ca qu trnh h hp nh cc ru, acetandehyt, axit acetic, axit lactic,gy bin mi, mt tnh min dch t nhin, sn phm c th b hng trc khixy ra cht t bo. V vy s gia tng ca qu trnh h hp ym kh cn ccoi nh mt hin tng bnh l khng c trng cho rau qu ti.

Nh vy, trong qu trnh BQ tri cy, cn phi to ra nhng iu kin mbo cho h hp vn xy ra bnh thng vi cng thp nht nhng mbo cho cc qu trnh trao i cht din ra bnh thng.

3. S sn sinh ethylene

1. Ethylene l mt hoc mn sinhtrng thc vt


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Ethylene l mt hoc mn sinh trng thc vt, l sn phm t nhin cathc vt c sn sinh ra trong qu trnh chuyn ha, c cu to ha hc ngin (C2H4), ng vai tr quan trng trong cc qu trnh sau y d ch lngrt nh (< 0,1 ppm):

o y mnh qu trnh chn ca qu h hp t bin;o Lm mt mu xanh trong mt s loi qu cn (qu c mi, da)

theo mong i ca th trng;o Nu ha cung, cnh (nho);o Lm m mm nt (da hu);o Lm rng i hoa, hoa v l;o Kch thch tng hp lignin lm mm cung

Nh vy, ethylene gy hiu qu rt r rt ln rt nhiu qu trnh sinh l caqu, c bit l qu trnh chn qu. Trong thc t, kch thch s chn ca qa

nhanh hn v ng lot, cn x l cc cht c kh nng sn sinh ra kh ethylenenh t n sn sinh ra kh acetylene. Vic x l ny c th thc hin trckhi thu hoch hoc sau khi thu hoch. Trong thc t, vic ethylene do tri cyt sinh ra trongqu trnh BQ gy ra hin tng qu nhanh chn, khng BQc ko di, c bit l i vi BQ cht ng trong kho. c ch s chnnhanh ca qu, cn BQ iu kin nhit thp hn ch s sn sinhethylene v x l cc cht hp ph ethylene. C th x l theo nhiu phng

php khc nhau: X l nhit khng nhng hn ch to ethylene ni sinh m cnhn ch c ethylene ngoi sinh. C nhiu nguyn nhn gii thch, nhng mttrong nhng nguyn nhn l nhit lm c ch enzyme tham gia tng hpethylene; Dng cht hp ph ethylene t trong ti bo qun hn ch s tothnh ethylene. Cc cht hp ph ethylene l cc hp cht ca ion Mangan, ccion Bc, c tnh oxy ha cao oxy ha cc ethylene ni sinh v ethylenengoi sinh to thnh kh cacbonic vnc. Cht hp ph ethylen AR3 do VinC in Nng nghip v Cng ngh sau thu hoch ch to c kimnghim tt trong bo qun mt s loi rau qu nhng nm gn y. AR3 l mthn hp ca cc hp cht oxy ho mnh v mt s cht ph gia c tc dngkh ethylene to thnh CO2v nc v nh vy s c ch qu trnh chn kodi thi gian bo qun. V d vi liu lng 5g ng trong mt ti nh t vo

ti mn 3kg c tc dng ko di thi gian bo qun khong qu t 20 - 40 giso vi mu i chng.Cch thc x l n gin v m bo an ton v sinhthc phm.

2. Ethylene l tc nhn lm hng qukhi BQ sau thu hoch


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Ethylene c sn sinh nhiu trong qu vo giai on qu trng thnh vchn. Tc dng ca ethylene l i khng vi cc cht kch thch sinh trng,n km hm s sinh trng ca qu v xc tin s chn.

Trong qu trnh chn ca qu, s tng hp ethylene tng ln rt mnh m.

Mc tng hp ethylene ph thuc vo tnh cht ca tng loi qu, lin quann tc C ca chng. Vi cc loi qu h hp t bin nh chui, xoi, mtth hm lng ethylene trong chng cao hn nhiu so vi cc loi qu h hpkhng t bin nh cam, chanh, bi, mn Hm lng ethylene ca qu tngrt nhanh giai on cui ca qu trnh tn ti ca qu trn cy.

3. Rm chn tri cy bng ethylene

Trong thc tin sn xut, vic lm nhanh chn, c bit l chn ng lot tiu th c ngha quan trng. Mt s cht ph bin rm chn tri cy trn thgii l:

o Ethrel: thng s dng ethrel phun cho qu trc khi thuhoch hai tun vi nng 500-5000 ppm

o t n (CaC2): dng rn, t n khi tc dng vi hi nc ctrong khng kh to ra axethylene, sau thnh ethylene. V d,rm chn chui bng t n, c mt tn chui cn 4-5 kg t n(tu theo cht lng t n), trong 12h, m lp y chuiln m t nhin trong khong 4-5 ngy (ty thi tit) cho n khi

chn hn.

4. C thu hi

1. C k thut

L C m qu c cc ch tiu k thut thch hp nht phc v mc ch sdng ca ngi sn xut (BQ hay ch bin). C c xc nh bng cc thngs k thut trong sn xut. C th thu hoch qu khi cn non (da chut bao t)hoc khi qu chn hon ton (da cho ch bin nc da).

2. C sinh l

Khi qu pht trin y cc thnh phn to nn qu, t ti a v kchthc, c hnh dng c nh v c kh nng chn bnh thng sau thu hoch. LC m qu c kh nng khng tt nht vi mi tc ng bn ngoi (thigian BQ di nht).


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3. C n c

Khi qu pht trin y cc thnh phn to nn qu, t ti a v kchthc, cc thnh phn ha hc trong qu bin i nhiu nht gip to nn ccch tiu c trng ca qu v trng thi, mu sc, mi v, hng thm, LC m ngi n c cm gic ngon nht.

4. Gi ci v hng

Qu qua giai on chn n c, cc ch tiu cht lng trng thi, dinhdng, mi v, gim r rt. Qu rt d b thi hng bi cc tc ng bnngoi mi trng.

2. Mt s yu t nh hng v nguyn nhn gy tntht

1. Nhit

1. Nhit cao

Nhit l yu t ca mi trng c nh hng quyt nh nht n qutrnh sng ca qu khi tn tr. Nhit BQ tng 10oC th phn ng ha hc,lng nhit sinh ra, cng h hp, t l hng tng 2-3 ln, hn na sn sinhethylene cng tng rt nhanh, do qu nhanh chn v cng nhanh chng dnn thi hng. BQ nhit an ton s gip ko di ti a thi gian BQ cngnh duy tr cht lng cho qu.

Bng 1. nh hng ca nhit n t l hng ca rau qu (loi khng tnthng lnh)

Nhit (oC)

Q10 Quan h tc hng

Quan h thiian bo

qun

Tn tht /ngy (%)

0 - 1,0 100 110 3,0 3,0 33 3


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20 2,5 7,5 13 830 2,0 15,0 7 1440 1,5 22,5 4 25

Ghi ch: Q10= T l hng nhit T+10 / t l hng nhit T

2. Tn thnglnh

BQ nhit thp hn nhit an ton s gy tn thng lnh cho qu.Tn thng lnh s lm gim cht lng sn phm, v rt ngn tui th BQ.Khi , cc t chc t bo b bin i, v mng t bo, gy tn tht cht dinhdng, cu trc bn trong b ph hoi mt phn, mu sc, mi v thay i, hnhdng rn nt, tp li, mt s loi tri cy s khng chn c. Ngoi ra, qutrnh chuyn ha bt thnh ng b gim i, cng h hp gim, vitamin C

b ph hy, s hot ng ca cc men b c ch, qu trnh trao i cht sngng li. Tn thng lnh ca qu cn do bn cht ca qu chi phi. Nhngvng sn xut khc nhau, C khc nhau, ma chn khc nhau th mc nhycm vi tn thng lnh cng khc nhau. Triu chng tn thng lnh ca ccloi qu khc nhau nh sau: Chui khi chn s b thm en; bi c cc vt so(bng), lm, sng nc; xoi c cc vt so mu xm, chn khng u; u c cc vt lm, khng chn c, km thm, thi hng; da khi chn s b xm;cam xut hin cc vt nu, lm... Cc triu chng ny thng xut hin khi asn phm tr li nhit m, nh l khi chng c em ra bn.

2. m tng i khng kh

m tng i ca khng kh trong phng BQ c nh hng ln n qutrnh BQ qu. m khng kh thp lm tng s bay hi nc, khi , mt mtqu b gim khi lng t nhin, mt khc lm ho b ngoi v bn trong, sinhra hin tng co nguyn sinh, dn n ri lon s trao i cht v qu mt khnng khng vi cc tc dng bt li t bn ngoi.

Tng m khng kh trong mi trng BQ va lm hn ch qu trnh h

hp, va m bo qu ti, khng ho (mt nc). Nhng nu tng mkhng kh cao qu th rau qu d b dnh bt, ngng t hi nc (t) trn bmt rau qu trong sut qu trnh BQ lm tng kh nng thi ra hn, gy tnthng b mt, c li cho VSV hat ng.

Trong qu trnh BQ qu, m ca kh quyn cn c duy tr ti u va chng bc hi nc li va hn ch c s pht trin ca VSV gy thi


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hng. V vy,thng thng vi loi qu c thi hn tn tr ngn th duy tr m khng kh 90 95 % chng mt hi nc lm ho. Cn vi loi qu ckh nng chng bc hi nc tt hn v tn tr c lu hn th cn gim m xung 80 90%.

3. thong kh

S thng gi v lm thong kh c nh hng quan trng n cht lngca qu ti trong qu trnh tn tr. Thng gi l i khng kh trong phngtn tr bng khng kh t bn ngoi vo. Cn lm thong kh l to ra schuyn ng ca lp khng kh xung quanh khi qu tn tr. S thng gi cnthit thay i nhit , m v thnh phn khng kh trong kho BQ. Trongqu trnh tn tr, tri cy c th sinh ra d nhit v d m. Nhit v m ny cth do h hp ca qu sinh ra c th do s bin ng ca nhit v m

ngoi tri. C th thng gi t nhin hay cng bc. Thng gi t nhin cto ra theo quy lut ca dng nhit. Khi h hp, khi tri cy pht nhit lmnng kh quyn trong phng tn tr, khng kh s gin n, nh i v cng hinc bc ln ri qua ng thot ra ngoi. Khong trng ny c b vo bngkhng kh t bn ngoi qua ng ht, khe ca v cc ch khc. Tc chuynng ca khng kh tc l hiu qu ca s thng gi t nhin ty thuc vo schnh lch nhit ti khi rau qu v bn ngoi, vo s chnh lch chiu caogia ni vo v ni ra ca khng kh.

m bo s thng gi t nhin c tt, nht l v ma h, qu ti cn

c tn tr cc kho thng thong, khng xp thnh ng qu ln v qu cao,phi c khong cch thch hp gia cc l v vi tng. Khng nguyn liuy hnh lang cn tr s thng gi vo phng. S thng gi t nhin ch pdng cho cc kho tn tr thng, lng va phi v xp chng khng qu cao.

thc hin thng gi cng bc, thng dng cc qut ht v qut y.Khng kh thi vo c th ly thng t kh quyn ngoi tri ch qua lc bihoc c th qua lm mt ti cc dn truyn nhit (dn nc lnh hay nc muilnh) hay lm m (qua mng nc phun sng) hoc lm kh (bngcht htm hay ngng t bt hi nc bng lm lnh ri hm nng li) ri mi thi vo

phng. cc kho tn tr hin i, c trang b h thng thng gi cng bct ng.

4. Mi trng kh quyn

Thnh phn ca kh quyn BQ c nh hng quan trng n qu trnh BQqu. Tng hm lng CO2v gim O2trong kh quyn c tc dng hn ch h


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hp (hiu kh) ca qu. Khi hm lng CO2tng ln n 3-5% v lng O2gim tng ng (ch cn 16-18%) th thi gian tn tr qu c th tng gp 3-4ln so vi khi gi kh quyn thng (0,03% CO2, 21% O2, 79% N2). Nhngnu CO2tng qu 10% s sinh ra qu trnh h hp ym kh,ph v cn bngcc qu trnh sinh l lm cho qu mt kh nng khng t nhin, dn n sthm en v thi hng. nh hng ca s thay i thnh phn kh quyn ntrao i cht trong qu rt phc tp, trc ht l s gim cng h hp vlm chm qu trnh chn tip. Khi duy tr c thnh phn kh quyn thch hpth cht lng qu c th cao hn c tn tr lnh.

5. Sinh vt hi (cn trng, VSV)

1. Cn trng

C rt nhiu loi cn trng ph hi qu trc v sau thu hoch. Sau y lmt s loi cn trng gy hi chnh trn qu sau thu hoch: rui c qu, suc tri, nhn , rp sp.

Rui c qu

o Tn khoa hc:Bactrocera correcta Bezz.o H Rui c qu:Trypetidae, B Hai cnh: Diptera

+ Triu chng

Rui gy hi trn nhiu loi cy n tri nh: thanh long, mn, vi, xoi,cam, v sa, to, u trng l di c vo trong qu, ch vt c bn ngoilc u l 1 chm en, sau ln dn c mu vng ri chuyn qua nu. Bn trongqu di c thnh ng hm vng vo lm qu b thi mm, d rng.

+c im hnh thi

RuiB. correcta c mu nu xm di khong 6-8mm, mt rui c vt enngang. Ngc trc thoi ha ch cn thy sau. Thy sau ngc trc mu vng,

hai bn sn pha trc gc cnh c mu vng, lng ngc gia mu en hocnu en. Gn gc chn cnh c 2 vt vng song song, cui vt vng c 1 lngcng. Chn ruimuhung.Trng rt nh, mu trngc hoc vng nht. Sunon l loi di c mu vng nht tri qua 3 tui, y sc di khong 6-7 mm.Khi di y sc chui ra ngoi ha nhng. Nhng dng nhng bc, mu nunht n nu m.

+ c im sinh hc v sinh thi


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Vng i: khong 22 ngy. Di n ra c vo trong qu gy hi. Trong qub hi thng c nhiu con di, y sc di chui ra ngoi ri xung t honhng hoc ho nhng trong qu b rng.

Rui c qu

- Tn khoa hc:Bactrocera dorsalis (Hendel)

o H Rui cqu:Trypetidae, B Hai cnh: Diptera

+ Triu chng

Loi rui ny l mt loi cn trng a thc; chng cn gy hi trn rt nhiuloi tri cy khc nh: xoi, thanh long, bi, vi, nhn, mn, hng b, toRui ci trng vo qu, di nra c ph lm cho qu b thi, rng gy

gim sn lng qu hng nm t 10-15%. L i tng kim dch quc t. Sph hi ca rui ny gy tr ngi cho vic xut khu hoa qu ca nc ta.

+ c im hnh thi

Con trng thnh ca chng l mt loi rui, c th di khong 7mm, cmu nu nht, mc d l rui nhng nhn chng c v ging con ong hn ruinh. Con ci dng ng trng chc thng v tri ri trng vo bn trong.


Rui ci dng ng trng chc thng v qu v trng vo ch tip gipv v tht qu. Sau khi khong 2 ngy th trng n ra con di. Sau khi ncon di c n phn tht qu xung quanh ch trng, cng ln chng cng crng v su vo bn trong n ph, lm cho qu b h thi, b rng v khng thn c. Nu b hi nng tri s b rng rt sm v rng hng lat, gy tht thurt ln cho nh vn.

y sc di c v tri chui ra ngoi, bng mnh ri xung t ri chui suxung t khong 3-7 cm lmnhng.

Mi nm loi rui ny pht sinh t 6-7 la.Trng thnh tng 5-10 qubn di v tri, v th khi b ra s thy c nhiu su non (di) nm bn trongtri. Mt rui ci c th t 150-200 qu trng.

Bin php phng tr rui c qu:


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Nu iu kin cho php, sau khi hnh thnh tri, dng bao giy, baonilon, bao chuyn dng...bao chm tri li, y l bin php thng chohiu qa rt cao khng phi s dng n thuc tr su, khng gy nhim cho mi trng v c hi cho ngi n, tuy nhin y cng lmt bin php kh tn cng sc ca nh vn.

Thng xuyn v sinh vn tc, ct ta nhng cnh, nhnh khng cnthit, to cho vn lun sch s, thng thong, hn ch ni tr ng cacon trng thnh.

Thu nht ht nhng tri rng di gc em tiu hy tiu dit di bntrong tri.

Thu hi tri sm hn bnh thng, khng tri chn qa lu trn cy. Dng thuc VIZUBON-D dn d v tiu dit con trng thnh. C th ri Basudin 10H, Vibasu 5H/10H; Paden 4G/10G, Regent

0,2G/0,3G... xung xung quanh gc dit nhng ang nm di t Khng nn dng thuc ho hc phun trc tip ln tri cy khi sp thu

hoch v rt d gy ng c cho ngi s dng, ht sc ch bo mthi gian cch ly ca thuc.

Su c qu

- Tn khoa hc: Conoghethes punctiferalis (Guenee)

- H Ngi sng: Pyralidae, B Cnh vy: Lepidoptera

+ Triu chng

Su c th gy hi trn xoi, i, thanh long v nhiu loi cy trng khc.Su c tri gy hi vo giai on tri trng thnh v chn, u trng sau khin c vo tri n phn tht hoc v ht to thnh nhng ng hm ngonngoo, i khi n c th c c vo ht.

+ c im hnh thi

Trng thnh l loi bm nh c chiu di thn khong 12mm, chiu disi cnh 25 mm, mu vng rm, trn cnh c nhiu chm nh mu en.

Trng thnh ci tng trng trn cung tri, trng hnh bu dc dp, kchthc khong 2 mm. u trng mi n c mu trng sa, u nu, sau chuynsang mu hng nht, y sc di 22 mm. Nhng mu nu nht c bao bc

bi mt kn bng t, su thng ho nhng k tri hoc ni tip gip gia 2tri.


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Vng i: 27-35 ngy: trng: 4-6 ngy; su non: 1416 ngy; nhng: 7-10ngy; trng thnh trng: 2-3 ngy.

Su gy hi lc tri cn non cho n khi sp thu hoch.

Bin php phng tr su c qu:

Trong t nhin trng su c tri b k sinh bi ong k sinh hTrichogrammatidae v kin, do to iu kin thun li cho cc loiny pht trin cng gim c thit hi do su gy ra.

Thu hoch tri sm khi tri chn, trnh tri chn qu lu trn cy. Bao tri bng bao nylong c c l. C th phun khi tri bt u chn bng cc loi thuc ha hc nh Decis,

Cymbush, Ambush, ch phi cch ly thuc trc khi thu hoch tri14 ngy.

Nhn hi cam chanh

- Tn khoa hc:Panonychus citri M.

- H: Tetranychidae, B: Acarina

+ Triu chng:

Nhn gy hitrn cam, qut, chanh, bi v nhiu loi cy trng khc.L loi su hi rt nh b, kh nhn c bng mt thng. Trng thnh chnh van, di t 0,3-0, 5mm mu nu . Trn qu nhn gy ra cc m snsi, lm gim nng sut v phm cht qu.

+ c im hnh thi

Trng thnh c kch thc rt nh, di khong 0,30-0,35 mm, mu camhay sm, hnh bu dc trn, trn c th c nhiu lng cng mc t u li

r rng. u trng mi n c mu vng hoc mu nu nht.Trng rt nh, hnh cu, pha trn c mt ci cung.


Thi gian sng ca nhn ko di t 10 15 ngy.
http://www.mard.gov.vn/PPDHCMC/html/Tailieukt/imageTailieukt/caq-ccmui-sau-nhendo-trai.gifhttp://www.mard.gov.vn/PPDHCMC/html/Tailieukt/imageTailieukt/caq-ccmui-sau-nhendo-trai.gifhttp://www.mard.gov.vn/PPDHCMC/html/Tailieukt/imageTailieukt/caq-ccmui-sau-nhendo-trai.gifhttp://www.mard.gov.vn/PPDHCMC/html/Tailieukt/imageTailieukt/caq-ccmui-sau-nhendo-trai.gif


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Trn tri, nhn thng sng tp trung phn cung tri, y tri v trong ccphn lm ca tri. Khi tri cn non nhn chch v ht dch lp biu b lm vtri b bin mu v cc vt thng kh li to nn nhng m sn si cnng dn gi l da lu, da cm, nh hng n v p ca tri.

Bin php phng tr nhn hi cam chanh:

Ta to tn cy cam chanh thng thong. Bn phn cn i; Nu c iu kin ti phun s lm gim mt nhn hi v t l n ca

trng. S dng thuc chn lc, trnh phun mt loi thuc nhiu ln, trnhphun

cc loi thuc qu c i vi thin ch ca nhn hi. p dng cc loi thuc ha hc cn ch : phun t u c hai mt l v

qu vi lng nc thuc 800l/ha v phun 2 ln vo cc thi im khi

hoa n xong v qu c ng knh 2cm. Cc loi thuc c th s dngl: Pegasus 500SC 0,1%; Ortus 5SC 0,1%, Danitol 10Ecn0,1% vi liulng 600-800l/ha.

Trong t nhin trng su c tri b k sinh bi ong k sinh hTrichogrammatidae v kin, do to iu kin thun li cho cc loiny pht trin cng gim c thit hi do su gy ra.

Rp sp

- Tn khoa hc:Pseudococcus sp.

- H Rp sp gi: Pseudococcidae

- B Cnh u: Homoptera

Rp sp l loi phn b rng nc ta. Chng c th gy hi trn nhiu loicy trng khc nhau nh xoi, cam, qut, bi, mn, da, chui.

L nhng cn trng nh b, kch thc t 1 - 4mm.

Cc loi rp sp u c chu k sinh trung ngn (khong 1 thng), kh nngsinh sn cao. Gy hi bng cch chch ht (u trng v trng thnh ci) tri,cung tri. Cc loi rp sp sng thnh tp on, tng m, bm dnh cht trnqu. Rp gy hi trn qu, lm gim cht lng sn phm. Ngoi ra rp spcng l mi gii truyn bnh virus.

Bin php phng tr rp sp:


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Phun nc vo tri ra tri rp sp trn tri. Ta b nhng tri b nhim giai on u. Thu hi nhng tri b hi nng em tiu hy. Trnh trng xen vi nhng loi cy d b rp sp nh mng ct, c ph. Phun thuc Pyrinex, Supracide, Basudin, Sagolex, Vidithoate, du

khong D-C Tron Plus... khi mt cao.

2. VSV

Sinh vt gy bnh l cc loi c th sng bao gm cc loi k sinh vt nhb nh vius, vi khun, nm, tuyn trng. Nhng sinh vt ni trn gy rabnh, gi l bnh truyn nhim. VSV gy hi trnqu thng thy l bnh thido nm v do vi khun gy ra. Sau y l mt s bnh thi hay gp trn qu:

Bnh thn th(cn gi l bnh m than)

- Tn khoa hc: Colletotrichum gloeosporioides.

+ Triu chng

Trn qu xoi: Thng b tn cng lc tri cn nh. Lc u l nhng chmmu nu nh, sau ln dn, lm xung c mu en, gy thi tri lc tn tr.

Trn qu thanh long: trn qu gi v chn c nhng m en hi trn lmvo v. Bnh pht trin mnh trong iu kin thi tit nng m ma nhiu.

+ Tc nhn

Bnh thn th xoi do nm Colletotrichum gloeosporides gy ra.

+c im pht sinh, pht trin ca bnh

Trn qu, m bnh tp trung nhiu trn cung, hay trn chp qu. Nm cth xm nhp vo cc l t nhin trn qu cn xanh. Khi bnh pht trin mnhs n su vo tht qu trong qu trnh tri chn.

Bin php phng tr bnh thn th hi xoi:

Bnh thn th trn xoi, thanh long th vic tiu hy cc cnh l, tri bbnh trnh ly lan l rt quan trng.

Trong ma ma c th phun nh k 7 ngy/ln cc loi thuc gc ngnh dung dch Bordeaux 1%, Copper zinc, Copper B hay Benomyl t


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khi hoa n cho n 2 thng, sau gim s ln phun khong 1 thngphun 1 ln.

Bnh thi qu (Phytophthora sp.)

Phytophthorasp. l nm a k ch, chng tn cng gy hi trn rt nhiuloi cy n tri nh cam, vi, da, nhn, da hu

+Triu chng

Bnh gy hi t qu xanh n qu chn. Giai on tri chn thbnh xuthin nhng m nu en,v sau ln dn v n su vo trong tri lm thi nhn.Tri thi c th cn trn cy hoc rng xung t.

+ Tc nhn

Do nmPhytophthorasp. gy ra. Si nm c cu to n bo, hnh thnhvi ht hnh tr hoc hnh cu trong qu trnh k sinhbn trong t bo cy.

NmPhytophthora.sp. c kh nng hnh thnh nhiu chng (race) khcnhau.

+ c im pht sinh, pht trin ca bnh

Bnh pht trin iu kin thi tit nng v ma nhiu, nht l cc chm

tri khut trong tn l. Cc vt chch ht ca cn trng trn tri to iu kincho nm pht trin.

Bin php phng tr:

Tiu hy cc tri b nhim bnh nhm hn ch ly lan. V sinh vn cyta tn to thng thong.

Khi thi tit ma nhiu c th phun thuc phng nga bnh cho cykhong 1 thng trc thu hoch bng cc loi thuc Viben, Dipomate,Mexyl - MZ, Mancozeb...theo nng khuyn co.

Bnh mc xanh v mc lc

(Penicillium italicum Wehmer vPenicillium digitatum Sacc)

Bnh gy hin tng thi qu cam, chanh, bi trc v sau thu hoch,trong thi gian BQ, ct tr v vn chuyn. nc ta bnh xut hin ph bin vn trng v cc kho BQ.


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+ Triu chng:

Bnh mc xanh v mc lc c c im chung l ch ph hi qu. Vtbnh thng xut hin cung qu hoc qua cc vt thng sy st. Lc u lim trn nh, mng nc mu vng nu, sau to dn, hi lm xung m

bnh thi ng. bnh mc xanh, b mt m bnh tng i rn, khng nhnnheo; cn bnh mc lc th b mt m bnh nhn nheo, n tay nh d v. Lcu trn b mt vt bnh thng mc ln mt lp nm mc trng. Sau , gia vt bnh lp mc chuyn sang dng bt mu xanh lc hoc mu xanh datri. Khi trn qu b c hai loi bnh, qu thi rt nhanh v to thnh hai lpnmhai mu xanh lam v xanh lc xen k, trong m qu c vt mu hng hochng ta.

+ Nguyn nhn gy bnh:

Nm mc xanh v nm lc u thuc nhm nm Bt ton

Nm mc xanh: si nm khng mu, ng knh 2-12m. Si nm mcxanh pht trin trong phm vi nhit 6 - 330C, thch hp nht nhit 270C.

Nm mc lc: si nm khng mu, ng knh 4 -20m. Si nm mc lcpht trin thch hp nht nhit 270C.

+ c im pht sinh pht trin bnh

Qua tip xc, nm cng d dng truyn lan t qu bnh sang qu lnh.

C hai bnh u pht trin thun li trong iu kin nhit cao. Phm vinhit l 6-330C, thch hp nht nhit 25-270C. Bnh pht sinh ph hinng trong trng hp b gip hoc c nhiu vt sy st, thu hoch vo thigian ma nhiu hoc nhiu sng. Qu cng chn cng d b nhim bnh.

Bin php phng tr:

Chn thi gian thch hp thu hi qu v bo v nm qu. Trnh lmdp v hoc gy sy st trong khi thu hi, ct tr v vn chuyn. Nn thuhi vo nhng ngy nng ro, khng ma.

Chn qu lnh ln ct tr bo qun, loi b ht nhng qu thi dphoc xy xt. Kho ct gi cn phi c kh trng, lm v sinh sch s,thong kh v c nhit thp. Thu hi kp thi khng qu qu chn.


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phng tr cc bnh ny c th x l qu bng dung dch Borac 5%trong 5 pht 430C hoc ngm qu vo nc mui 0,4% trong thi gian2 pht.

Bnh lot cy c mi (Xanthomonas citri Dowson)

+ Triu chng

Bnh gy hi trn cnh non, trn l v qu. Vt bnh lc u l cc mn snkhong 3-5mm, sau chuyn sang mu nu vng, xung quanh c vin muvng.

Trn qu: vt bnh rn, x x mu nu hi lm, mp ngoi c g ni ln, gia vt bnh m cht rn nt, vt bnh thng lm vo. Cc vt bnh thngni lin nhau thnh tng m c th sinh ra chy gm. Ton b chiu dy ca

v qu c th b lot, nhng vt lot khng n su vo rut qu. Bnh nng cth lm cho qu bin dng t nhiu, qu t nc, kh sm, d rng. Bnh lmcho qu xu m, khng t cht lng v TC xut khu, mt khc vt bnhlot l tin m ng cho nhng k sinh th cp xm nhim.

+ Nguyn nhn gy bnh

Vi khun gy bnh lot l loiXanthomonas citri. Vi khun hnh gy ngn,kch thc 1,5-2 x 0,5- 0,75m, c 1 lng roi u, nhum gram m, ho kh.Vi khun xm nhim vo cy qua l kh, kh khng v qua vt thng sy st.

+ c im pht sinh pht trin bnh

Thi k tim dc ca bnh thay i ty thuc vo cc ging cam bi, mc thnh thc ca cy b bnh v ph thuc vo iu kin nhit . Vi khun

pht trin mnh nhit 20-300C, nhit 520C trong 10 pht th vi khuns b cht. Vi khun c kh nng chu hn, chu lnh cao.

Trn cc cy c mi th cy bi nhim bnh lot nng nht, ri sau lcam chanh, cc ging qut c tnh chng bnh mnh hn.

Bin php phng tr:

Phng chng bnh lot cy c mi phi kt hp nhiu bin php trong quan trng nht l bin php chn ging chng bnh, tiu dit ngun

bnh, bin php canh tc v phun thuc bo v theo mt h thng tnghp.


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Tiu dit ngun bnh: thu dn sch tn d, b phn b bnh trong vnm cng nh trong vn qu; thng xuyn ta l, cnh b bnh trongvn um; dng cc mt ghp khng b bnh, gc ghp chng chu

bnh. Phng tr bnh bng bin php k thut canh tc: bn phn vo thi k

thch hp, bn cn i cho cy pht trin bnh thng. Pht trin trng cc ging cam qut chng chu bnh lot. Bin php ha hc: dng thuc Boocdo 1% phun bo v phng chng

bnh t khi ra lc xun c 20 ngy. Phun bo v qu nn bt u tlc hoa tn, sau 50-60 ngy cn phun thuc lp li phng tr bnh.

Bnh thi tri da

+ Nguyn nhn gy bnh: do nm men Saccharomyces spp.

Nm men l mt loi sinh vt rt ph bin trong t nhin, chng xut hintrong tri qu chn hoc tri b tn thng.

+ Triu chng v thit hi:

Nm men ln men ng, sn sinh ra ru v phng thch CO2, Triuchng u tin l xut hin cc bt kh c gas v nc qu qua vt nt hoc tnthng nhng ni nhim bnh. V tri chuyn sang nu v v tri dy ln,khi tri chy nc lm cho tht tri b rng bn trong.

+ Phng nga

Thu hoch khi tri va chn ti. Trnh s dng tri c triu chng nt chotiu th ti.

Bnh thi tri da, chui

+ Nguyn nhn gy bnh: do nm Thielaviopsis paradoxa

+ Triu chng v thit hi :

Nm bnh c th tn cng ngay vt ct ca cung tri lm thi cung tri vy tri, nmcng tn cng tri b tn thng trong lc vn chuyn. Trn quchui nm tn cng lm qu chui b thi en. Nhit v m cao l 2 yut gia tng t l bnh v tri da, chui s thi rt nhanh.

+ Phng nga:


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Thu hoch cn thn trnh lm tri b sy st, loi b tri b tn thng.Dng c bao b phi sch khi vn chuyn v tn tr tri.

Bnh thn th chui

nc ta bnh pht trin quanh nm. Bnh thng ph hi qu vo thik thu hoch, rm chn v vn chuyn.

+ Triu chng bnh:

Bnh ch yu ph hi qu thnh thc sp chn v chn, bnh hi ccung qu, thn bung.Vt bnh thng tp trung phn u qu.Lc u l chm nh mu nu nht hi lm, hnh trn v sau vt bnhlan rng c mu nu sm hoc en, nhiu vt bnh c th lin kt nhau,

sau 2-3 ngy qu thi nhn. Trn b mt vt bnh c nhiu chm nh ccht dnh mu hng nht.

Vt bnh cung qu v cung bung cng c mu en t, trn b mtc lp nm mu trng.

Hnh 15. Bnh thn th trn chui


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+ Nguyn nhn gy bnh:

Nm gy bnh thn th Colletotrichum musae (Berk and Curt) thuc nhmnm Bt ton. Trong iu kin t nhin nm ch c giai on v tnh. Nhit thch hp cho nm pht trin v hnh thnh l 27-300C. S ny mm ca bo t

nm m 92%. Bnh pht sinh mnh trong iu kin m cao. Chui tiub bnh nng hn chui ty v chui l.

Bin php phng tr:

Chm sc tt vn chui, ct b phn cung bung khi pht hin bnh. Khi thu hoch chui trnh lm sy st, kh trng dng c, thu hoch khi

qu cn xanh. Lm v sinh tt ni ng gi v BQ, vn chuyn chui. C th dng tia

garna dit ngun bnh.

Bnh thi nu qu mn

NmMonilinia fructicolal nguyn nhn chnh gy nn bnh thi nu, mtloi bnh ph bin v rt nguy hi cho mn.

Bo t ca cc loi chng VSV trn l lng trong khng kh, c cc dngkhng kh khuch tn i khp ni, tip cn vi qu. Gp iu kin thun li,chng s ny mm v bm su vo v qu.

Khi qu chuyn sang trng thi chn, nhng hot ng ca chng mi btu xy ra. Lng bo t c to ra cng nhiu v xut hin s ly nhim tnhng bnh ra cc qu kho mnh khc. V th, s thi hng thng xuthin khi qu chn trong khi vn chuyn hoc sau khi BQ lnh.


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Bnh m qu trn thanh long

Hai i tng dch hi quan trng nht lm nh hng v gy cn tr nvic xut khu thanh long qu ti ca nc ta hin nay l rui c qu(Bactrocera dorsalis Hendel,Bactrocera correcta) v bnh m qu do nm

Fusarium lateritium gy ra.

Khuyn co i vi b con nng dn, cc nh vn, cc doanh nghip trngv xut khu thanh long qu ti bin php x l bnh m qu v dit ruic qu thanh long nh sau:

X l nhit (hi nc nng) i vi qu thanh long 46,5 C dit rui

c qu trong thi gian 20-30 pht, sau kt hp BQ trong phng lnh nhit 5 C c tc dng tt hn ch pht trin ca bnhm gy thi bn trongv bn ngoi qu do nmFusarium lateritium.

Nu khng c kho lnh m phi BQ trong iu kin thng thng th cnphi chn lc loi b tt c cc qu c du vt bnh d ln hay nh trc.

3. K thut SCBQ c bn

1. S ch: nh s ch, lm sch, phn loi, baob

1. Nh s ch

1. Chc nng nhim v nh s ch

Nh s ch l ni din ra cc hot ng chnh trong x l sau thu hochnng sn bao gm cc khu phn loi, lm sch, x l BQ, ng gi, lm lnh,BQ, v vn chuyn c thc hin bi thit b v con ngi nhm hn ch thp

nht s tn tht sau thu hoch, tng cht lng cui cng v gi tr th trngca sn phm nng nghip.

2. c tnh nh s ch


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Nh s ch trc ht l mt khng gian m mi hot ng sau thu hochc thc hin trong . Thit b c b tr trong nh s ch hp l,thun tin cho hot ng sau thu hoch.

Ph thuc vo tng mc ch, yu cu s dng m nh s ch c th rtn gin ch l mt khong khng thch hp c mi che, thng t tirung, vn thc hin nhng hot ng n gin khng i hi k thutcao. Thit b b tr trong nh s ch n gin (bn thao tc, chu ra,).

Nh s ch hin i c xy dng c nh, thit k m bo thongkh, nh sng v v sinh. Nh s ch tt nht khi c h thng lm lnh.Thit b c b tr trong nh s ch ny c th l n gin nhng thngthng l tng i hin i, ng b. Thit b s thay th nhiu sc laong ca con ngi.

Do i hi ca sn phm v s phc tp ca nh s ch hin i, ngicng nhn phi c o to, lnh ngh trong cng vic.

2. Lm sch

Vic lm sch qu trc khi BQ c thc hin khc nhau i vi mi loiqu khc nhau. C loi cn lm sch bng ra nc nh chui, xoi, u ;c loi ch c lau nh bi, cam, v c loi khng c ra nc nh: na,da,. Vic lm sch l rt cn thit, va gip loi b tp cht v c v huc.

1. Tp cht v c

Tp cht v c bao gm cc bi bn, t, ct v nhng tp cht khng phnhy c khc bm trn bmt qu hay ln trong khi qu trc v trong qutrnh thu hoch, vn chuyn.

2. Tp cht hu c

Tp cht hu c bao gm cung, cnh, l, rc, su b, VSV, nha m caqu; cc qu lp, nh, thi, khuyt tt, tn thng v nhng tp cht c th

phn hy c khc c trn b mt v qu hay ln trong khi qu trc v

trong qu trnh thu hoch, vn chuyn.

3. Lm sch bng nc

Lm sch bng nc c thc hin lm sch cc tp cht v c v huc trn mt s loi qu. Vic lm sch bng nc c th thc hin n gindi vi nc sch ang chy hoc nc sc kh khuy trn. Tt hn, vic lm


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sch nn c thc hin vi h thng thit b ra cng nc ra c pha thuckh trng chlo. C th pha 1- 2 ml Chlo trong 1 lt nc sch s to ra dungdch Chlo 100 150 ppm. pH ca nc ra nn c gi 6,5 7,5 l ttnht.

4. Lm sch bng dng kh thi

Loi b cc tp cht bng vic s dng dng khng kh mnh thi ln bmt qu. Bin php ny c th c p dng cho nhng loi qu cn lm schm khng c ra nc. Vic ny c thc hin vi thit b lm sch qu

bng kh nn.

3. Phn loi

Phn loi bt u bng vic loi b nhng qu km cht lng, hoc bkhuyt tt (nhng qu b rn nt, bin dng, thi hng, su bnh, hoc b ccvt thng c hc). Nhng qu c cht lng tt sau s tip tc c phnloi theo kch thc, khi lng, mu sc

Phn loi s gip trnh c s h hng sm ca qu. Nu ln cc loiqu khc nhau v cht lng, qu b bnh hoc b tn thng vi cc qu lnhln s lm tng t l thi hng, v qu cht lng km hoc qu b tn thngrt nhy cm vi s pht sinh bnh, d dng b nhim bnh t qu b bnh, vc th dn n h hng c nhng qu tt khc. Qu b bnh hoc b tn thng

c hc thng sn sinh ra nhiu ethylene, thc y qu trnh chn v gi ho.Cng khng nn ln qu cha chn vi qu chn, c bit l trong sut thigian di vn chuyn v lu tr, v qu chn s sinh ra lng ethylene cao, gyra s chn sm canhng qu cha chn khc.

1. Phn loi theo kch thc, khilng, mu sc

Vic la chn qu c kch thc, khi lng v mu sc ng u trongcng mt l BQ c ngha rt quan trng khng ch vi ngi tiu dng vmt cm quan v thng phm m cn bi qu c kch thc, khi lng, musc khc nhau c th s khc nhau v cht lng l, ha hc v cc hot ngsinh l nh s trao i cht v mc tng hp ethylene

Vic phn loi qu theo kch thc, khi lng, mu sc c th c thchin ch quan bng mt hoc c s h tr ca cc thit b o nh cn, thc,my o mu sc. Cng c th s dng mt s cng c phn loi n gin hay


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phc tp c th cho tng loi qu khc nhau. Cc sn phm c hnh trn cth c phn loi bng l trn xc nh nhiu kch c khc nhau nh bn

phn loi kiu bc thang, bn v tr cao nht c l ln nht, bn v tr thpnht c l nh nht. Qu c kch thc ln nht khng lt qua cc l bn thnht c ly i, cc qu c kch thc nh hnlt qua l c chuyn xung

bn th hai v c tip tc nh th. Mt s cng c phn loi khc nh mngphn loi, bng ti c cc khe h kch thc, hnh dng khc nhau c thit kring cho tng loi qu.

2. Phn loi theo cht lng l hc, hahc

Qu c cht lng l hc, ha hc khc nhau nn c tn tr ring v nhy cm vi nhng tn thng c hc, v tc C ca chng khng ging

nhau. Nhng qu mm hn cn c ring trnh b mp bp, nt v nhtl i vi qu phi vn chuyn i xa. Nhng qu c thnh phn ha hc nhhm lng ng, axt khc nhau c tc C khc nhau trong qu trnh BQcng nn c phn loi ring.

4. Bao b

1. Bao b BQ

Bao b BQ l nhng loi bao b dng bao gi qu trong qu trnh BQ vimc ch gi gn cht lng v ko di thi gian BQ ca chng. Mi loi quthch hp vi mt loi bao b BQ ring. Bao b BQ tt nht cho qu l bao bc m bo hn ch c tn thng c hc, khng b ng nc, c tnhthm kh ph hp, chng tia t ngoi, chng tnh in., khng c. Vt liulm bao b BQ c th l cht do, giy nhng ph bin l cc loi mng chtdo nh: Polyethylene (PE) ; High density polyethylene (HDPE) ; Linear lowdensity polyethylene (LLDPE); Low density polyethylene (LDPE); Mediumdensity polyethylene (MDPE); Polybutylene (PB); Polyethylene terephthalate(PET); Polyolefin; Polypropylene (PP); Polystyrene (PS); Polyvinyl butyral

(PVB); Polyvinyl chloride (PVC); Polyvinylidene chloride (PVDC)

2. Bao b vn chuyn

Bao b vn chuync s dng trong thi gian vn chuyn sn phm tni thu hi n nh s ch BQ hoc t nh s ch BQ n ni tiu th. Bao bvn chuyn c tnh ton thit k ngoi tc dng bo v hng ha cn gip


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h tr vic tn tr trong sut qu trnh vn chuyn, phn phi v tiu th trnth trng, v c th hn ch ti a cc va chm khi vn chuyn trong iu kinxu. Bao b vn chuyn cn m bo sch s, c chc chn, chu c plc khi chng xp, thng gi tt, khng sc cnh, c th tch hp l cc qunm di khng b chn p Vt liu chnh thng c s dng lm bao bvn chuyn bao gm st tre, thng g, thng nha, thng carton, bao ti siay, si vi, si nha an,.... C th s dng cc vt liu mm lt m nhrm, l cy, giy vn, bo c, xp, mtkt hp vi bao b BQ nhm hn chcc tn thng c hc i vi qu trong qu trnh vn chuyn.

2. BQ

1. BQ bng nhit

1. X l BQ bng nhit cao, thigian ngn

S dng k thut x l nc nng hoc khng kh nng trong thi gianngn nhm ngn nga cc yu t bn ngoi (v sinh sch) v bn trong (c chhot ng ca enzim) ri lm mt ngay nhm trnh h hi nhanh sn phm.

X l bng dng khng kh nhit cao (HTFA) l mt trong nhngphng php x l sau thu hoch c pht trin t nhng nm 1920 cho nnay vn c s dng. HTFA l mt dng s dng khng kh nng kt hp vi m tng i khng kh RH thp nhm gim h hi sn phm. Thngthng i vi mt s loi qu, nhit x l 49-53oC trong thi gian 3-10

pht

2. BQ mt (cooling)

Trong sut thi gian tn tr qu, gi v kim sot nhit l yu t quantrng nht duy tr cht lng. Gi qu nhit an ton ca n s tng tui

th sau thu hoch. Mi loi qu thch hp vi mt nhit BQ khc nhau, nhit thp hn d b tn thng lnh, nhit cao hn s nhanh thi hng. ivi nhm qu nhit i (nhm 1) nhy cm vi tn thng lnh nh chui, quc mi, vi, nhn, xoi, u , da, chm chm nhit an ton BQ lkhong 8-13oC. Trong cc trng hp c bit, nhit bo qun an ton cth thay i.


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3. BQ lnh ng (freezing)

BQ qu bng nhit lnh ch c th BQ c t vi tun n vi thng tyloi. Mun BQ c lu hn na, t 3-4 thng n hng nm th phi BQ lnhng. Khi lm lnh ng qu, lc u cc tinh th to thnh t nc gian

bo, sau ti nc thnh t bo, ri tip tc trong dch bo v nguyn sinhcht mi dn dn chuyn thnh . n cui cng qu trnh lnh ng cng vncn mt lng nc khng ng bng c, l phn nc lin kt bn vngnht m trong rau qu lnh ng thng chim t 6-8%.

Do chuyn thnh nc nn sn phm qu lnh ng tr thnh cng, cmu trng sng hn, c khi lng ring nh hn (v trong ng bng th tchnc thng tng khong 10%) v c s thay i cc thng s nhit vt l .Cng v nc ng bng nn nng dch bo qu tng, p sut thm thu

tng, pH gim nn c tc dng km hm mnh hot ng ca VSV. VSV cn bkm hm mnh lit hn do nc ng bng nn khng cn mi trng m hot ng. Nu lnh ng qu t nhit m 18oC th lng nc ng

bng ti 86%, tc lng m cn li ch 14%. Trong khi , loi nm mc hotng khan nc nht cng cn n 15% m. Mc ng bng nc trit

ph mi trng sng ca VSV l mt trong nhng TC ca k thut lnh ngrau qu, chnh v vy, m t lu th gii quy nh lnh ng thc phm n -18oC. Ngy nay, vi loi thc phm nhiu ng, nhiu vitamin nh rau qucn tr ng nhit thp hn nn TC BQ thay i t -18oC xung -25oC.C cc phng php lnh ng nh: lnh ng dng bung (thi gian lnh

ng ko di 15-20 gi); lnh ng dng bn (thi gian lnh ng ko di 20pht n 3 gi); lnh ng nhanh - IQF (thi gian lnh ng t 5-10 pht).

2. X l BQ bng cc ch phm ho hc

Cc ch phm ho hc s dng trong BQ ch yu l hn ch qu trnh xy ha v phng dit VSV. Khi s dng cc ch phm ho hc trong BQ qucn lu ch s dng cc ch phm c trong danh mc c php s dng vvi liu lng trong gii hn cho php v tun th ng quy nh v thi giancch li khng lm nh hng n sc khe ngi tiu dng.

hn ch qu trnh xy ha ca qu ti trong qu trnh BQ phi dng cccht kh mnh c tc dng gim lng oxy c trong cc t bo qu, tng cng, gim s sn sinh ethylene ni sinh v ngoi sinh, iu chnh pH kmhm cc phn ng nu ha bt li cho qu. Cc ch phm ph bin c sdng l: SO2, vitamin C, KMnO4, CaCl2, 1-MCP, axit xi tric


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Cc ch phm ha hc thng c dng phng v tr bnh cho qu l:lu hunh, mui Canxi hypoclorit (dng bt) v Natri hypoclorit (dng lng).Qu c th c ra trong dung dch hypoclorit (dung dch Clo 25 ppm), sau scra, s kim sot c thi hng do vi khun gy ra. Hoc hypoclorit(dung dch Clo 50-70ppm) sau ra di vi nc sch kim sot vikhun, nm men v nm mc. Cc mui bicacbonat bao gm: Natricacbonathay cn gi l bt Soda hay bt n (NaHCO3), Kalicacbonat (KHCO3). Mt sch phm khc dit nm nh: vi bt, dung dch phn 15% (15g Nhmkalisulphat trong 100 ml nc) bi cung; Topsin-M 0,1% BQ chui, camti; Benlat 0,2-0,3%; Mertect 0,4-0,5%, Atonic, Carbedazim...

Chi tit danh mc cc ch phm ho hc, thuc BVTV v liu lng cphp s dng tham kho :

o Quyt nh s 867/1998/Q-BYT ngy 04/04/1998 ca B

trng B Y t v vic Ban hnh Danh mc TC v sinh i vilng thc, thc phm

o Quyt nh 23/2007/Q - BNN ngy 28 thng 3 nm 2007 caB trng B Nng nghip v pht trin nng thn v vic banhnh danh mc thuc bo v thc vt c php s dng,hn chs dng, cm s dng Vit Nam

3. BQ bng chiu x

BQ bng chiu x l mt phng php hin i p dngthnh tu ca vt lht nhn vo BQ thc phm ch bin cng nh ti sng. Nguyn l BQ caphng php ny l: chiu tia bc x vo b mt sn phm mt mt tiu ditVSV, mt khc c ch qu trnh sinh l, sinh ho (i vi rau qu ti) nh vyko di c thi hn BQ. Khi s dng bc x ion vi liu lng cho php BQ thc phm, khng gy ra c t, c hi, s thay i cht lng dinhdng do bc x khng ln hn do cc phng php khc.

Bng 2. Quy nh v liu chiu x i vi rau qu ti

(Theo Quyt nh S: 3616 /2004/Q-BYT ca B trng B Y t v vic banhnh Quy nh v sinh an ton i vi thc phm BQ bng phng php

chiu x )

Mc ch chiu x Liu hp th ti a (kGy)*Ti thiu Ti a

Lm chm qu trnh 0,3 1,0


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chnDit cn trng, k sinhtrng

0,3 1,0

Ko di thi gian BQ 1,0 2,5

X l kim dch 0,2 1,0

Ghi ch: *Liu hp th l t s gia de v dm, trong de l nng lnghp th trung bnh (tnh bng jun) m bc x ion ha truyn cho khi thc

phm c khi lng l dm (tnh bng kilogam).n v liu hp th l Gray (khiu l Gy), 1Gy=1j/kg, 1kGy=1000 Gy.

u im ca phng php ny l nhanh, thun tin, c th rau qu trongbao b khi x l nn t b ti nhim, khng li d lng ha chtc hi trni tng chiu x, tit kim nng lng , c th iu khin theo mun

m bo yu cu v cht lng ,bo tn cc ch tiu vt l , ha hc, sinh l.Gi thnh tn tr rau qu ti theo phng php chiu x r, bng 50% tn trlnh.

Nhc im ca tia bc x i vi qu ti l lm gim sc khng cachng, v cc nguyn nhn sau:

o Lm gim kh nng to mng bo v (da non) cc vt thng;o Lm mm qu v chia ct mch xenluloza v protopectin;o Lm tng thm thu ca t bo, do vy y mnh qu trnh trao

i cht, lm cc thnh phn dinh dng b hao tn;o Ph hoi mt s cn bng trao i cht, ch yu l trao i nng

lng, do hn ch s xy ha lm cho kh nng t khngca qu i vi VSV gim;

o Hnh thi t bodi ra, c ch phnh ra, c ch teo li khng bnhthng.

4. BQ bng mi trng kh iu chnh(Control atmosphere-CA)

Mi trng kh iu chnh l mi trng kh c to ra m trong t lthnh phn cc kh N2, O2 v CO2khc vi khng kh bnhthng (khong79% N2; 20,9% O2; 0,03%CO2v cn li l mt s t cc kh khc) v gi nng trong sut thi gian BQ. BQ bng mi trng kh iu chnh l BQtrong phng kn, c h thng thng gi v cung cp cc kh O2, N2 v CO2vithit b o nhit , m v nng cc kh ny mt cch t ng v c


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kim sot cht ch. Do thit b t tin, chi ph tn tr cao nn phng phpny t ph bin d cht lng BQ rt cao.

Bng 3. Nng kh thch hp cho mt s tri cy

Loi qu Nng kh O2 (%) ng kh CO2 (%)Chui 2-5 2-5Vi 3-5 3-5Xoi 3-7 5-8Cam 5-10 0-5

Da 2-5 5-10Mn 1-2 0-5

Bi 3-10 5-10u 2-5 5-8

1. Mi trng nng O2thp

Oxy gy ra thi hng do qu trnh oxy ho thc phm v kch thch s phttrin ca VSV. i vi phng php CA, oxy c th b loi tr, nhng khnghon ton v n thng l mt nguyn nhn tt khng ch cht lng baogm:

+ Duy tr ti, mu t nhin.

+ Duy tr h hp ca rau, qu.

+ Ngn nga s pht trin ca VSV ym kh.

Rt nhiu phn ng sinh l ca qu sau thu hoch xc tc bi enzim cnoxy. Khi thnh phn khng kh BQ c thnh phn O2gim th mc O2thnh t bo gim, tc phn ng ho hc gim v s trao i gim.

nhhng bt li ca mc O2thp l s tch t ethanol v acetaldehyt lmmt mi qu. Mc O2thp c th gy h hp ym kh cc thnh t bo


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nh hng ca vic gim nng oxy trong khng kh BQ vi cc loi quc tm tt di y:

o Gim cng h hp;o Gim s xy ha cc cht;o Lm chm chn qu h hp t bin;o Ko di thi gian BQ qu;o Lm chm phn hy chlorophill;o Gim s sn sinh ethylene;o Thay i s tng hp axt bo;o Gim t l phn hy pectin ha tan;o Hnh thnh hng v khng mong mun, bin i trng thi;o Pht trin nhngri lon sinh l

2.

Mi trng nng CO2 caoKh CO2 ngn nga s pht trin mnh ca cc loi vi khun v nm mc

hiu kh. Theo nguyn tc chung mc CO2cng cao th cng ko di thi gianBQ.

Tuy nhin CO2d b hp th bi cc cht bo v nc nn phn ln thcphm hp th CO2.

mc CO2cao c th gy ra thi hng, mt nc v gy p cht bao bvo sn phm.

Lng CO2 khng ch s pht trin ca mc v vi khun ti thiu l20%.

Kh CO2c tc dng ko di thi gian BQ v gim cng h hp. Ngnnga hot ng ca mt s enzim tham gia vo qu trnh trao i cht ca chutrnh h hp ca qu.

Ngi ta chng minh c nng CO2cao khi BQ c th cnh tranhvi nh hng ca ethylene cc v tr linkt ni trong t bo qu (Burg1967). Nng CO2khong 10% th hot tnh sinh hc ca 1% ethylene ivi qu b mt. Yang (1985) chng minh rng CO2tch t trong khoang t

bo ca qu nh l cht knh ch vi ethylene.

S ri lon sinh l ca qu vi mc CO2qu cao c th lin quan ti sngt on, chuyn hng ca cc phn ng trong chu trnh h hp v dn ti stch t ru v aldehyt.


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Mc CO2 cao (10- 15%) c th c ch s pht trin nm mc ca mt sloi qu.

Ko di thi gian gi qu mi trng c nng CO2cao dn n s hhng ca qu. Nhng nu gi mt thi gian nht nh (v d 2 ln trong mt

tun vi thi gian mi ln l 10 gi) sau vn gi iu kin thng th lic li cho BQ du ty, gim s thi hng qu.

Khi tng mc CO2trong BQ c cc nh hng c tm tt nh sau:

o Gim cc phn ng tng hp qu h hp t bin;o Gim mc C;o Ngn chn vi phn ng enzim;o Gim s sn sinh cc hp cht bay hi hu c;o Bin i s chuyn ha cc axt hu c;o Gim t l phn hy cc hp cht pectin;o Hn ch phn hy chlorophill;o Gy mt mi sn phm;o Ri lon sinh l bc u;o Lm chm s pht trin VSV;o Gim nh hng ca ethylene;o Thay i hm lng ng;o Duy tr c tnh cht ti ca qu;o Gim s chuyn mu sc

3. Mi trng nng CO2rt cao(Shock CO2)

X l qu vi mc CO2cao trc ri sau mi em BQ c hiu qu cao ko di thi gian BQ. X l vi mc CO2cao trong mt thi gian ngn nhtnh ph thuc vo loi rauqu gi l sc (shock) CO2. Nng CO2x l rtcao c th c tc dng:

o Hn ch s to thnh carotenoid, gi mu xanh v qu;o Tng cng sau BQ;o Sn sinh CO2, ethylene, ethanol v ethyl acetate, lm qu mm v

vng hn nhng v tt hn;o Gim t l nu ha, ri lon sinh l mt s qu

5. BQ bng bao gi kh iu bin (ModifiedAtmosphere Packaging - MAP)


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C cc cch nh ngha MAP nh sau:

Kh iu bin (MA) l to ra mi trng m trong t l thnh phn cc khN2, O2 v CO2khc vi khng kh thng v c s thay i lin tc qua chu kBQ bi cc yu t h hp, sinh ho v thm chm qua bao b. Phng php to

ra kh iu bin (MA) trong mi trng BQ bng cch dng mt s bao b bao gi gi l MAP).

MAP l mt dng bao gi nhm iu chnh thnh phn kh quyn xung quanhsn phm c bao gi lm gim cng h hp ca sn phm v c chhot ng ca VSV. Kt qu ko di thi gian BQ v duy tr c tnh t nhinca sn phm. y l phng php BQ da trn nguyn l tim sinhAnabioza.

MAP l s t sa i thnh phn kh xung quanh rau qu c dn kn trong

ti bng mng cht do nh h hp v khuych tn hoc MAP l la chnthnh phn kh xung quanh rau qu ti trong bao b cht do dn kn saocho rau qu vn h hp c.

1. MAP th ng

Trong qu trnh BQ, thnh phn kh trong bao gi c th b thay i thngqua vic gim nng O2 v sinh ra kh CO2. Mng bao gi phi cho php khO2t bn ngoi thm vo trong bao gi vi t l bng chnh lng O2do qutiu th. Tng t, kh CO2phi thm ra bn ngoi ti bao gi bng nglng CO2sinh ra. Thnh phn kh lun phi c thit lp nhanh do trongtrng hp thiu kh O2c th dn n sn phm h hp ym kh hay thnh

phn kh CO2cao c th dn n ri lon sinh l cho sn phm. Phng phpMAP th ng p dng ch yu trong BQ rau, qu ti, p ng tt ti nhit v m ca mi trng n nh.

2. MAP tch cc

Phng php MAP tch cc c iu chnh thnh phn kh thng qua vic

ht chn khng v thay th ch ng bng hn hp kh yu cu vo bao gi.Hn hp kh ny c th c iu chnh thng qua k thut ht kh O2 ra hocs dng cht hpph kh O2, CO2 hoc C2H4. Phng php ch yu hin nayc s dng hp th kh O2l da trn nguyn l oxy ho Fe. Mt vi

phng php khc c s dng bng phn ng enzim Glucose oxidase. Chthp th kh CO2hin nay ch yu c dng l Ca (OH)2

.


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3. MAP c l

Mng to l nh (bng tia la in) hoc mng bn thm hoc thng quamt l nh c gn ln mt phn ca bao b nhm kim sot s khuych tnkh O

2v CO

2gia mi trng bn trong v bn ngoi bao gi to ra mi

trng kh quyn mong mun. Khi , s khuych tn kh gia mi trng bntrong v bn ngoi ti trng thi cn bng kh c thit lp cht ch.

6. BQ bng mng bc bn thm(Waxing/Coating)

Mng bn thm l mng mng bao quanh lp v qu c kh nng hn chs thot hi nc v lm gim s trao i kh (ch yu l kh O2 v CO2) caqu c bc mng. Lp mng ny to ra s khc bit kh quyn gia bn

ngoi (mi trng BQ) vi phn tip xc trc tip ca qu v iu chnh qutrnh trao i kh ca qu, do lm chm qu trnh h hp. Mt khc mng

bc cn c chc nng bo v lm gim h hng trong qu trnh vn chuyncng nh s xm nhp ca VSV t mi trng xung quanh.

Qu c th c nhng trong hn hp cht lng hoc dng hn hp chtlng phun hoc tri trn b mt ca qu, sau c lm kh nhn to hoc tnhin khi trn b mt qu s hnh thnhmt lp mng mng khng thmnc v ng nht lin tc. Mng bc bn thm c th c to ra t mt loi

polyme hay t hn hp cc polyme khc nhau v bn cht ha hc ca polyme

quyt nh tnh cht ca mng bc. Mng bn thm c th n c hoc khngn c.

1. Mng bn thm n c

Mng bn thm n c thng c dng cho cc loi qu n c v nh:mn, m, i, nho, du ty, ... Mng bn thm n c c th c lm t nhiungun protein, khc nhau. Cc ngun protein c dng lm mng bn thm nc gm c zein ca ng, gluten ca la m, protein u tng, protein sa vcc protein c ngun gc ng vt nh collagen, keratin v gelatin. Ngoi ra,mng bn thm n c cn c lm t cc vt liu n c khc nh: CMC(Carboxyl methyl cellulose), Chitosan, tinh bt, whey protein, gluten bt m,tinh bt khoai mn, sp cht bo

2. Mng bn thm khng n c


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Mng bn thm khng n c thng c dng cho cc loi qu n b vnh: bi, cam, qut, da, mng ct, ...Vt liu to mng bn thm khng nc l cc cht khng n c nh: polyethylene, keo, nha cnh kin

7.

BQ bng kt hp hai hoc nhiu phngphp BQ

Kt hp mt cch hp l gia hai hay nhiu bin php BQ s tng ng khiu qu BQ qu. C nhiu bin php BQ kt hp,ph bin l kt hp gia xl ha cht, iu chnh kh, chiu x,bao gi vi nhit thp , hay kt hpgia x l ha cht, bao gi v nhit thp hoc kt hp gia chiu x, baogi vi nhit thp. Bin php tt nht ko di thi hn BQ qu tihin nay l h thp nhit mi trng, kt hp vi CA (kh quyn kim sot)hoc MAP (bao gi kh quyn iu chnh) hoc coating m khng phi dng

n ha cht hay phng tin no khc.

3. Cht lng

Cht lng l tp hp cc ctnh ca mt thc th (i tng) to chothc th (i tng) kh nng tha mn nhng nhu cu nu ra hoc timn (Theo TCVN TCVN 5814-1994 ph hp vi ISO 8402-1994)

Cc lai nng sn hng ha khc nhau vi th trng tiu th khc nhau sc nhng qui nh v cht lng cng khc nhau.

Sn phm c cht lng l lun lun p ng yu cu ca khch hng. Micng vic sn xut, kinh doanh mt sn phm c cht lng l lun lun c sn

phm c cht lng mt cch c hiu qu nht, vi chi ph thp nht. Tt c cch thng cht lng phi t mc tiu ny.

Ty thuc th trng theo khng gian v thi gian nht nh, m cht lngt mt hoc nhiu nhm cht lng nh:

i. cht lng thng mi,

ii. cht lng dinh dng,iii. cht lng nu nngiv. cht lng n ung vi cc ch tiu chi tit c cp phn

trn.

Cht lng phi lun c nng cao nhm p ng c i hi ca thtrng pht trin th sn phm mi mang tnh cnh tranh cao. Do vy, khi


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nim cht lng sn phm khng phi l c nh, n c th thay i theo thigian v khng gian, ph thuc vo ngi tiu dng cui cng. Tuy nhin, cth ni: Cht lng ca mt sn phm hoc dch v ch c th nh gi bingi mua sn phn hay dch v . chnh l khch hng.

Ngoi ra, nn hiu r cht lng tt khng c ngha l cht lng cao.iu quan trng l sn phm hay dch v p ng hoc tha mn c yucu ca khch hng.

c im ca cht lng.

o Cht lng c th c p dng cho mi thc th.o Cht lng phi l mt tp hp cc c tnh ca thc th th hin

kh nng tha mn nhu cu.o Mt thc th d p ng c TC nhng khng ph hp vi nhu

cu, khng c th trng chp nhn th vn phi b coi l khngcht lng. y cnphn bit gia cht lng v cp chtlng.

o Cht lng phi c gn lin vi iu kin c th ca nhu cu,ca th trng v cc mt kinh t, k thut, x hi, phong tc, tpqun.

o Cht lng c o bi s tha mn nhu cu. S tha mn nyphi c th hin trn nhiu phng din: tnh nng ca snphm, gi tha mn nhu cu, thi im cung cp, dch v, anton hnh thnh khi nim cht lng tng hp. Cc phngdin ny c th tm lc qua qui tc 3P hoc QCDSS.

Qui tc 3P:

o Performance, Perfectibility - Hiu nng, kh nng hon thin.o Price - Gi tha mn nhu cu.o Punctuality - Thi im cung cp.

Qui tc QCDSS:


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o QualityCht lng.o CostChi ph.o Delivery TimingGiao hng ng thi hn.o ServiceDch v.o SafetyAn ton

1. TC cht lng (QS)

L tp hp cc gi tr c lng ha v c tnh hoc ch tiu ca snphm c qui nh. TC cht lng c qui nh nhiu cp nh cp c s(TCCS), cp quc gia (TCVN), cp quc t (ISO, AOAC, Codex). Trongtrng hp c bit, c qui nh theo tha thun ca hai hoc nhiu bn thamgia.

Ch , TCN (TCN) hin nay khng c xy dng na nhng vn cn gitr tham kho

2. Kim tra cht lng (QC)

L hot ng nh o, xem xt, th nghim hoc nh c mt hay nhiu ctnh ca i tng v so snh kt qu vi yu cu qui nh nhm xc nh s

ph hp ca mi c tnh.

3. Qun l cht lng (QM)

Cht lng l kt qu tc ng ca hng lot cc yu t c lin quan chtch vi nhau. Mun t c cht lng mong mun, cn phi qun l mtcch ng n cc yu t ny. Hot ng qun l trong lnh vc cht lngc gi l qun l cht lng. H thng qun l cht lng l h thng qunl nh hng v kim sot mt t chc v cht lng.

Mt s cc h thng qun l cht lng nng sn thc phm :

a) H thng qun l cht lng theo TC quc t ISO 9000

ISO 9000 l b TC do T chc TC quc t (The International Organizationfor Standardization- ISO)ban hnh vo nm 1987 nhm a ra cc chun mccho h thng qun l cht lng v c th p dng rng ri trong cc lnh vcsn xut, kinh doanh v dch v.


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ISO 9000 cp n cc lnh vc ch yu trong qun l cht lng: chnhsch v ch o v cht lng, nghin cu th trng, thitk v trin khai sn

phm, cung ng, kim sot qu trnh, bao gi, phn phi, dch v sau khi bn,xem xt nh gi ni b, kim sot ti liu, o to,

ISO 9000 l tp hp cc kinh nghim qun l cht lng tt nht cthc thi nhiu quc gia v khu vc, ng thi c chp nhn thnh TC qucgia ca nhiu nc.

H thng qun l cht lng theo ISO 9000 da trn m hnh qun l theoqu trnh, ly phng nga lm phng chm ch yu trong sut vng i casn phm. B TC ISO 9000 bao gm rt nhiu TC nh ISO 9001, 9002, 9003vv.

b) H thng thc hnh sn xut tt (Good Manufacturing Practices -GMP): l mt h thng m bo cht lng, v sinh, an ton c p dng ivi cc c s sn xut, ch bin thc phm v dc phm.

GMP a ra cc yu cu nhm kim sot tt c cc yu t nh hng ti qutrnh hnh thnh cht lng t thit k, xy lp nh xng, thit b, dng c ch

bin, bao gi, BQ v con ngi iu khin cc hot ng ch bin.

C th, GMP a ra cc yu cu sau:

o Nh xng: khi thit k hoc s dng nhng nh xng c,

phi ch n cc yu cu v v tr, din tch, thong, vt liuxy dng, thit k, m bo khng gy nhim bn vo sn

phm.o Phng tin ch bin: bao gm cc yu cu i viphng tin

v sinh, phng tin chiu sng, phng tin thng gi, h thngmy mc, thit b, dng c dng cho sn xut, h thng thit bm bo an ton.

o Yu cu v sc khe ngi lao ng: c ch khm sc khethng xuyn pht hin, iu tr v cch ly nhng cng nhnmc bnh truyn nhim hoc ly lan. C ch v sinh c th i

vi cng nhn m bo khng b nhim bn sn phm.o V sinh: bao gm cc yu cu v x l cht thi, BQ ha cht c

hi, kim sot sinh vt gy hi, dng c nhn.o Qui trnh sn xut (ch bin): bao gm cc yu cu v kim sot

nguyn vt liu v kim sot cc hot ng sn xut (ch bin).o BQ v phn phi: bao gm cc yu cu v kim sot cc iu

kin, phng tin BQ, phn phi.


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Ni chung, GMP a ranhng yu cu chung, c bn v l nhng iukin tin quyt m bo v sinh v an ton i vi thc phm, dc phm.

c)H thng thc hnh nng nghip tt ( Good Agricultural Practice -GAP)

L sng kin ca nhng nh bn l chu u (Euro-Retailer ProduceWorking Group) nhm gii quyt mi quan h bnh ng v trch nhim giangi sn xut sn phm nng nghip v khch hng ca h. H a ra khinim GAP v ngy nay n tr thnh 1 trong nhng h thng qun l chtlng nng sn tt nht v c nhiu quc gia trn th gii p dng. GAPc chia ra lm 2 h thng chnh bao gm :

- EUREPGAP: v mt k thut, EurepGAP l mt ti liu c tnh cht quychun cho vic chng nhn ging nh ISO trn ton th gii

Quy nh ca EUREPGAP phin bn 2.1/2004 bao gm 14 vn :

o Truy nguyn ngun gc;o Lu tr h s v kim tra ni b;o Ging cy trng;o Lch s v qun l vng t;o Qun l t v cc cht nn;o S dng phn bn;o Ti tiu v bn phn qua h thng ti;o Bo v thcvt (BVTV);o Thu hoch;o Vn hnh sn phm;o Qun l nhim cht thi, ti s dng cht thi;o Sc khe, an ton v an sinh ca ngi lao ng;o Vn mi trng;o n khiu ni.

- ASEANGAP: trc y 10 nc thnh vin ca ASEAN cam kt gia tngcht lng v gi tr ca sn phm rau v qu. T yu cu cc nc thnh

vin bt u gii thiu nhng quy nh v m bo cht lng m nng dnphi tun th. Nhng gn y mt vi nc thnh vin nhn ra s cn thitphi c h thng m bo cht lng (Quality Assurance-QA) nn pht trinchng thnh nhng TC nh:

- H thng kim sot cht lng SALM (The Farmer Accreditation Schemeof Malaysia) ca Malaysia.


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- H thng m bo cht lng da trn nhng quy nh v thc phm anton ca Philipphin.

- H thng m bo cht lng v an ton thc phm (QA) ca Singaporepht trin t Indonesia-nh cung cp ch yu sn phm cho h.

- H thng tng t (Q) ca Thi lan.

Tuy nhin nhng h thng m bo cht lng ny bao trm nhng khacnh m TC GAP yu cu. T cc nc thnh vin quan tm v m rngh thng QA cho khi ASEAN da trn yu cu an ton thc phm. Nhngquy nh c chun ha mc chung nht cho khu vc ASEAN c gil ASEAN GAP v nphi l mt TC hi ha ph hp vi cc nc thnh vinn nm 2020.

Quy nh ca ASEAN GAP phin bn 1.0 bao gm 7 vn :

Lch s v qun l a im sn xut; Vt liu gieo trng; Phn bn v cht ph gia cho t; Ti tiu; BVTV; Thu hoch vx l rau qu; Qun l trang tri.

d) Th tc tc nghip v sinh chun (Sanitation Standard OperatingProcedure-SSOP).

SSOP cp n cc vn v v sinh lin quan n an ton thc phm vv sinh mi trng nh:

o An ton ngun nc v h thng sn xut nc.o Cc b mt tip xc trc tip sn phm.o B tr dy chuyn sn xut ngn nga s nhim cho.o Kh trng tay v v sinh c nhn.o BQ sn phm, bao b.o BQ v s dng ha cht c tnh c hi.o Kim sot v tiu dit sinh vt gy hi.o Kim sot tnh trng sc khe cng nhn vin.


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Mt khi SSOP c thc hin tt s gip cho vic thit lp h thng qun lGMP c d dng hn.

e) H thng phn tch cc mi nguy v kim sot cc im ti hn -HACCP

HACCP ( Hazard Analysis and Critical Control Point) l cng c nhgi cc mi nguy hi v lp cc h thng tp trung vo cc bin php phngnga thay cho vic ch th nghim thnh phm. Gi tr ca HACCP l c thc p dng trong sut dy chuyn ch bin thc phm, t ngi sn xut banu n ngi s dng cui cng. Ngoi vic nng cao tnh an ton ca thc

phm, HACCP cng to iu kin s dng cc ngun lc hiu qu hn v png cc yu cu kp thi hn, ng thi h tr cho hot ng kim tra v chngnhn ca ccc quan c thm quyn.

HACCP bao gm 7 nguyn tc c bn sau:

1. Phn tch mi nguy hi (Hazard Analysis HA): nhm xc nh minguy hi tim n mi giai on c th nh hng ti an ton thc

phm. T , nh gi kh nng xut hin v ra cc bin php kimsot chng.

2. Xc nh cc im kim sot ti hn (Critical Control Point CCP):nhm xc nh cc im cn phi c kim sot ti cc cng on ch

bin loi b hoc hn ch kh nng xut hin ca cc mi nguy hi.3. Xc lp cc ngng ti hn: nhm xy dng cc ngng m qu trnh

sn xut khng vt qu m bo khng ch c hiu qu cc imkim sot ti hn.

4. Thit lp h thng gim st cc im kim sot ti hn: nhm xy dngmt h thng cc chng trnh th nghim, quan st gim st ccim kim sot ti hn.

5. Xc nh cc hot ng khc phc: nhm xc nh cc hot ng khcphc cn phi tin hnh khi h thng gim st cho thy c mt im tihn no khng c kim sot y .

6. Xc lp cc th tc thm nh: nhm khng nh rng h thng HACCPang hot ng c hiu qu.

7. Thit lp h thng h s ti liu: nhm thit lp mt h thng ti liulin quan n mi th tc, hot ng ca chng trnh HACCP.

Da theo 7 nguyn tc trn y, xy dng nn cc bc p dng c th, tvic thnh lp nhm cng tc chu trch nhim chnh trong vic p dng hthng HACCP ti c s, n vic thit lp cc th tc thm nh, thit lp h


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thng h s, ti liu. C th thy rng, cc iu kin m bo an ton caHACCP l rt kht khe.

4. m bo cht lng (QA)

L ton b cc hot ng c k hoch, c h thng c tin hnh trong hthng qun l cht lng v c chng minh l mc cn thit to s tintng tha ng rng thc th s tha mn y cc yu cu cht lng.

Cc bin php m bo cht lng:

Cam kt cho cht lngo Cng b chnh sch cht lng.o ra nhng mc tiu phn u cho cht lng.

Chng minh kh nng kim sat cht lngo Phn cng ngi i din chu trch nhim v hat ng cht

lng.o Phn cng trch nhim quyn hn y v r rt. o C mt h thng ti liu y cc yu t cn kim sot.

Chng minh kh nng duy tr kim sot cht lngo H thng h s cht lng c xy dng v lu tr.o Duy tr cc hot ng khc phc phng nga v sa i nhng

iu khng ph hp (mang tnh thng xuyn v nh k).

4. m bo VSATTP

1. D lng thuc BVTV v ha cht BQ

L lng thuc BVTV (BVTV) v ha cht BQ cn tn ti trong sn phmnng nghip vt qu mc cho php (ngng an ton) ca cc c quan chcnng trong nc v th gii trc khi s dng.


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Tn ti thuc BVTV v ha cht BQ c tc hi trc tip n sc khe conngi, vt nui (gy ng c) v tc ng xu n mi trng t, nc, khngkh. D lng thuc BVTV v ha cht BQ trong rau qu lm gim cht lnghng ha, gim sc cnh tranh ca hng ha nng nghip trn th trng quct.

Nguyn nhn dn n d lng thuc BVTV v ha cht BQ c th do:

Dng sai v liu lng s dng. Khng m bo thi gian cch ly. Dng thuc khng r ngun gc, thuc b cm s dng,

Bng 4. V d d lng cho php ca mt s ha cht BVTV

(Ban hnh km theo Quyt nh s 867/1998/Q-BYT ca B trng B Y t

ngy 4 thng 4 nm 1998)

Tn thng dng Tn ha hc Thc phm Gii hntn d tia (mg/kg)

Azinphos-methyl S-3,4 - dihydro - 4-oxo- 1,2, 3

benzotriazin

Qu o 4

Captan N-

(trichloromethylthio)cyclohex-4-ene-1,2-dicarboximide

Cam, qut, o,

du ty, to

15

Carbaryl I-naphthylmethylcarbamate

Mn, anh o,m

10

Cholorfenvinphos 2-chloro-1- (2,4-dichlorophenyl) vinyldiethyl phosphate

Cam, qut 1

2. VSV gy bnh

VSV gy bnh l cc loi virus, vi khun, nm men, nm mc trong quc th gy bnh trc tip cho ngi, vt nui khi n phi.

VSV gy bnh c rt nhiu trong mi trng khng kh v c trn b mthu ht cc loi qu m mt thng khng nhn thy. VSV pht trin mnh v


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tng ln rt nhiu v s lng khi qu b tn thng v iu kin BQ khnghp l.

S lng v chng loi VSV gy bnh ph thuc nhiu vo c im cuto thnh t bo ca tng loi qu, mi loi qu c cc chng VSV ring bit,

chng va l nguyn nhn gy thi hng qu va c kh nng gy bnh khixm nhp vo c th.

Bng 5. Vd v qui nh mt s VSV v s lng cho php c trong thcphm

Thc phm VSV Gii hn cho php trong 1g hay 1ml thchm

Sn phm thcphm

Coliforms

E. coli

S. aureus

Cl. perfringens

B. cereus

Salmonella*

103

102

102

102

102

0

(*) Salmonella: khng c c trong 25g thc phm.

3. c t do VSV gy ra

Mt s loi VSV c kh nng sinh ra c t khi c mt trn b mt rau qu.Cc c t ny c hai loi l ni ct v ngoi ct:

Ni c t (endotoxin) l c t c to thnh v lin kt vithnh tbo ca VSV. c t ny ch gii phng ra ngoi (gy c) khi t boVSV b cht hoc b phn hy (ph v).

Ngoi c t (enterotoxin) l c t do VSV sinh ra trong t bo sau tit ra ngoi. Dng c t ny c tnh c rt cao.

4. K thut SCBQ mt s loi qu


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1. Phng php SCBQ chui

p dng chnh cho chui tiu

1. TC nguyn liu, dng c, thit b, khotng

Nguyn liu (TCVN 1872-86; TCN 568-2003):

Trng thi: qu nguyn vn, pht trin t nhin, khng gip, gy, nt, cnhqu hitrn, nhng cn r cnh. Khng cho php qu dnh i, d dng.

Mu sc: v qu mu xanh, ti, kh ro, sch s. Khng cho php v qub rm nng, rm mui, thm en, dnh nha, dnh bi t.

Hng v: cn v cht, khng c mi c trng ca chui chn

Ch tiu ha hc:

Bng 6. Ch tiu ha hc ca chui

Ch tiu Hm lngCht kh

Axit

ng

Tinh bt

3-3,8oBx

0,2-0,36%

0,7-0,15%

16,4-21%

D lng thuc BVTV: Carbouran < 0,1mg/kg; Thiabendazole


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Kho BQ.

2. S quy trnh

3. Thuyt minh quy trnh

Chm sc v phng tr su bnh (BVTV):

- Vi vng sn xut chui ngoi bi nn t ph sa pha ct, b Basilepta gyhi nhiu nn p dng bin php phng tr su hi bng ha cht kt hpthng xuyn v sinh ng rung nh:

+ Ta bt cy con, ct b v t ht l kh, lp l b v thn kh.

+ Phun tr su trng thnh bng Dipterex 90 nng 0,1% c pha thmcht bm dnh Thin nng nng 0,1 %, lng dung dch phun 500 lt/ha.Phun 4 t trong nm; 2 t vo thng 4 v 2 t vo thng 7, mi t cchnhau 15 ngy.

- Vi vng sn xut chui trong : p dng lun canh cy trng phngtrnh tc hi ca su gm v Basilepta.

X l sau khi chui tr hoa:


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Phun Dipterex 90 nng 0,1% c pha thm cht bm dnh Thin nngnng 0,1 % ln cy ngay sau khi tr hoa, lng phun 500 lt/ha.

Bc bung

thi im bp mi tr thng cha cong gc xung, dng ti PE mu xanhda tri c kch thc 140 80 cm c c l vi din tch 2% so vi tngdin tch b mt ca ti to thng thong. Ch dng ko ct to 2 l nh cng knh khong 1cm y di ca mi ti thot nc khi tri ma.Phn ming ti c buc vo cung ca mi bung chui.

Vi vic p dng cc k thut x l trc thu hoch nh trn, t l chuixanh khi thu hoch t TC 10 TCN 568-2003 tng ln ng k so vi tnhin.

Thu hoch

Xc nh chn (C) thu hi

Qu chui tiu ti i din xc nh C l qu gia v hngngoi ca ni chui: c hnh dng bnh thng, khng d dng trong kinmu ly ngu nhin t l hng.

Chui tiu thu hoch thng thng giai on 1 theo tiu chun (TC)quc t PCI (bng chun mu sc v qu) c cc c trng sau:

Quan st mu sc v qu, trng thi lin kt gia v qu v tht qu: vqu c mu xanh lc hoc xanh sng, v qu cn dnh st vo tht qu vkh bc.

Quan st hnh dng bn ngoi ca qu chui: cnh ca qu cng trn thqu cng gi

Quan st mu sc, trng thi tht qu: tht qucng, chc, b d gy, cmu trng ng.

Quan st trng thi t nha ca qu chui: khi b qu c t nha dnh vtrong, nha khng chy thnh git.

Xc nh mi v tht qu bng cm quan: tht qu cn v cht, cha c

mi c trng ca chui chn. Thi im thu hi: nn thu hoch chui vo bui sm, khi tri kh ro. Cch thu hi: mt ngi bung, mt ngi dng dao chuyn dng

cht t bung mt cch dt khot. bung chui theo chiu dngng xung t mt cch nh nhng. Dng dy buc vo cung bungv gnh v ni tp kt.


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Pha ni:

Ti ni tp kt, cc bung chui c trong bng rm xp theo chiudng ng ngc xung t da vo nhau, gia cc bung nn chn l chuikh hn ch sy st do tip xc. Ty theo mc ch sdng, chui c pha

ni bng dao Ecuador (chui xut khu), hoc dao thng (chui tiu th trongnc). Khng s dng ni u bung v 1-2 ni cui bung.

X l sau thu hoch

Chui sau khi pha ni c ngm ngay vo nc v ra loi b m,bi v mt phn cn trng, VSV c trn v chui. Sau 5-10 pht ngmra bng nc l, chui c chuyn sang ngm trong nc Javen.

Ngm nc Javen: chui sau khi c ngm ra s b bng nc ls c ngm trong dung dch nc Javen nng 0,1% trong thi gian

10 pht nhm mc ch tiu dit mt s VSV b mt. X l ha cht dit nm bnh: sau khi c ngm nc Javen, chui

c x l bng cch ngm trong dung dch CBZ 0,05% trong thi gian2 pht, sau c vt ra v ro nc.

Bao gi, ghi nhn, vn chuyn: theo TCVN 1872-86; Tiu chun ngnh(TCN) 568-2003.

Ghi nhn:

Bn ngoi bao b ng chui tiu phi c nhn ghi r rng bng mc khngphai theo ni dung sau:

Tn ngi bn hng. Tn ngi mua hng. Tn hng. Khi lng tnh. Khi lng c b.

C th ghi nhn theo quy nh trong hp ng i ngoi.

ng gi

Chui tiu tiu th dng ni phi c ng gi trong baopolyethylene c dn y v t trong bao b cartn lnh, chc chn,kh, sch, khng b mc, mt, mc i, khng c mi v l gy nh hngn phm cht qu. Thnh thng carton phi c l nhng v tr qui


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nh. Cho php s dng nhng loi bao b khc nhau theo tha thuntrong hp ng i ngoi.

Khi xp chui vo bao b phi xp ng nitheo kiu xp tha, cungquay vo trong. Trn cung ni v gia hai lp ni phi c lt bnggiy mm. Trong mt kin khng c xp qu 2 lp ni. Cho php cthm 1-2 chm qu trong mi kin hng m bo khi lng tnh.

Khi lng tnh ca mi kin l 10 kg hoc 15 kg. Trong mi kin chui phi c phiu ng gi (bng ting Vit hoc ting

nc mua hng yu cu) theo ni dung sau: Tn hng. Tn n v sn xut. Tn n v bao gi. Khi lng tnh. Ngy ng gi. Tn ngi ng gi.

Vn chuyn

Cc phng tin vn chuyn chui phi kh ro, sch s, thong mt, cmi che, khng c mi v l v cc cht c hi gy nh hng n

phm cht chui. Phi c bin php chn lt chng va chm khi vnchuyn, tt nht l vn chuyn bng xechuyn dng c iu ha nhit.

Bc xp chui phi nh nhng, khng va chm mnh v qung qut kinhng lm gip qu.

Cc kin hng phi c xp chc chn, trnh ri ro cho sn phm tibn trong trong qu trnh vn chuyn.

Cc kin hng c xp st nhau thnh mt khi chc chn, cc l thnggi trn thnh kin hng phi c xp thng hng m bo thnggi cho sn phm bn trong.

Cho php to khe h m bo thng gi trong mt khi hng bngcch: c mi hai hng ngang kin hng c chn np g dy khong1cm theo phng thng ng. Cc np g c chn sao cho khngc che l thng gi trn thnh kin hng.

BQ

BQ nhit thng:

Kho BQ chui phi kh ro, sch s, thong mt, khng c mi v l,khng cc hng ha c mi v l chung vi chui.


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Cc kin chui phi c xp cch tng t nht 0,6 m, c xp ln ccbc g cch nn kho t nht 0,3 m, v phi m bo thng gi cho cckin hng.

Nhit BQ trong phng khng qu 30oC, thi gian BQ c 7 ngy.

BQ lnh:

Nhit BQ ti u ca chui ti ty thuc vo C, iu kin v sinh,thi gian vn chuyn chui ti n ni tiu th.

i vi chui ti C thu hoch 1 CPI, nhit BQ ti u l1214oC, vi m tng i ca khng kh t 85-90%.

Cc kin chui c xp cao khong 5 - 8 lp kin, ty theo cht lngbao b cc-tng v khi lng tnh ca kin chui tiu.

Thi gian BQ ti a c 30 ngy.

Rm chn v tiu th

Sau khi BQ, trc khi chun b tiu th, chui c x l rm chn bngdung dch rm Ethrel 0,15-0,2 % bng cch ngm trong dung dch ny trongthi gian 2 pht, ro nc v nhit khong 22-25oC. Sau khong 5ngy chui s chn, c mu vng c trng, chui chn t mc Rt thch nh gi cm quan theo thang Hedonic (t 8,1 im). Tin hnh x l rm 4-5ngy trc khi c k hoch tiu th.

4. Cht lng sn phm

Ch tiu cm quan

Bng 7. Cht lng cm quan ca chui sau BQ

Ch tiu Yu cuTrng thi Qu khng mm

Mu sc V qu mu vng p ( thang 6 PCI)Hng v V ngt nh, khng chua

Ch tiu l, ha

Bng 8. Cht lng dinh dng ca chui sau BQ


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Ch tiu Yu cuHm lng ng 18%Hm lng tinh bt2,5%

Ch tiu VSATTP(TCN 418-2000)

Tng s VSV (TCP): 104 CFU. Vi khun Samonella: khng c trong 25g sn phm. Vi khun E.coli: khng c. D lng thuc BVTV: Carbouran < 0,1mg/kg; Thiabendazole


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in (kho lnh) ging nhau

Cng 215 000 250 200T l thi hng 65,27 % kg 652,7 5 000 3 263 500-T l thi hng 8,63 % kg 86,3 5 000 - 431 500

Tng cng 3 478 500681 700

Li ch do vic BQ bng phng php MAP so vi phng php truynthng c tnh trn vic chi ph thm cho BQ nhng mang li kt qu l hnch c t l thi hng nh sau:

6 185 800 876 000 = 2 796 800 ng / tn chuinguyn liu

Nh vy, nu p dng phng php BQ MAP cho chui nhit lnh thtng thm l 2 796 800 ng/tn so vi phng php truyn thng.

Ch

Quy trnh trn c th p dng cho cc ging chui khc v trng cc vngmin khc nhau.

Trong trng hp BQ chui nhit thng th theo thng s sau y:

Chui nguyn liu giai on 1 theo TC quc t PCI. Bao b LDPE; 10m. Nhit BQ khng ln hn 30oC. B qua cng on lm lnh. Thi gian BQ khng ln hn 10 ngy, t l tntht nh hn 9,1%.

2. Phng php SCBQ da

p dng cho c ging Cayenne v ging Queen.

1. TC nguyn liu, dng c, thit b, khotng

Nguyn liu:


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- tiu th v ch bin trong nc: (p ng TC da qu ti tiu chunVit Nam (TCVN) TCVN 5002-89)

Qu nguyn vn, ti, sch, chc, c chi ngn v mt phn cung, mtqu cng, m to; khng b rm nng, st, gip. Trn qu khng c cn

trng nhn thy c. Tht qu chc, khng nht, c mu trng ng n vng, mi thm c

trng ca da chn, v chua ngt n ngt, khng c v l.

- xut khu: (p ng TC da qu ti xut khu 10 TCN 567-2003)

Qu nguyn vn, ti, sch, hnh dng t nhin, mt qu cng, m to;khng b rm nng, st, gip khng c vt nt d lnh; c chingn v cung.

Chi ngn p, thng, khng di hn 150% so vi chiu di qu. Cung qu sch, khng di qu 2 cm, mt ct vung gc cung. Tht qu chc, khng nht, c mu trng ng n vng, mi thm c

trng ca da chin, v chua ngt n ngt, khng c v l. Mt ct ngang qu khng c vt nu hoc thm.

- Da cho tiu th v ch bin trong nc cng nh xut khu c chialm 3 C theo mu sc v qu nh sau:

C 1: m mt ton qu, c k vng 1-2 hng mt phn cung qu. C 2: qu c mu vng 1/3 v qu tr xung. C 3: qu c mu vng 1/3 n 2/3 v qu.

Dng c, thit b, kho tng: bao gm

Cc dng c, phng tin thu gom, vn chuyn da t ni thu hoch v niSCBQ nh bao, r, st, xe th s, xe ti chuyn dng,: phi kh, thong,sch, khng mc, mt, khng c mi l v ha cht c hi nh hng n chtlng qu; phng tin thu gom, vn chuyn phi c che chn v chu lc tt trnh ma, nng v ri qu trong khi vn chuyn.

Kho, ln trung chuyn n niSCBQ hay nh, kho SCBQ: phi kh ro,sch, thong mt, khng c mi l nh hng n cht lng qu, khng chaha cht c hi hay hng ha c mi l chung vi da trong kho.

Hp carton hay hp g, nha, tre xp da trong SCBQ: phi kh, sch,khng mc, mt, khng c mi l nh hng n cht lng qu; chu lc tt,n nh cao bo v c qu bn trong khi xp chng trong thi gian ng


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gi v vn chuyn ng di, thnh hp c c l thng gi tt. Trn hpphi c nhn ghi r c im v k m hiu hng ha theo ng Quy ch luthng hng ha s 178/1999/Q-TTg ngy 30/8/1999.

2. S quy trnh

3. Thuyt minh quy trnh

Thu hi:

Khi qu t cc C 2 v hm lng ng trong qu t ti thiu 10oBrix (kim tra qu ngay trn ng). Hi qu bng tay la chn chnh xc quv mu sc, kch thc theo yu cu. Khi thu hoch dng tay xon cung qucho ri khi cy. Khng thu hi vo nhng ngy ma hoc nng gt.

Xp vo phng tin thu gom, vn chuyn:

Xp da thu hi c vo bao, st, r, . chuyn n phng tinchuyn ch. Xp nh nhng, cn thn, trnh gy bm gip, trnh lm gy cungv chi ngn. cc nng tri ln v trang b k thut tin tin, da thu hixong c chuyn n phng tin chuyn ch bng cc bng ti b tr dctheo cc hang da gim h hng do va p n mc thp nht


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Vn chuyn v ni SCBQ:

Vi lng da ln, c th vn chuyn bng t, da c xp ng trnsn xe lt rm di y v bn thnh xe; xp qu ng thng, cung quayxung di, xen k nhau hoc da c cha trong cc st, thng ri xp ln

sn xe. Vi lng vn chuyn nh c th vn chuyn bng xe my, da ccha trong cc st, thng hoc trong bao.

Xp ng

Ni cht ng da tm thi ch chuyn i trn ng rung phi ch rmmt, kh sch.

La chn, Xn cung:

loi b cc qu khng t yu cu cht lng nh qu c vt rm, gipnt, su bnh, qu cn xanh, qu chn hay qu b.

Cung qu c xn gn gim cng bao gi v th tch bao gi, vnchuyn v tiu th sau ny. Khi xn phi dng dao sc, sch, cung qu cn lisau xn di 1-2 cm, mt ct vung gc vi cung.

X l cht dit nm hoc sp:

phng trnh cc bnh qu do nm,vi khun gy ra trong thi gian vn

chuyn, BQ nh thi nhn, thi en mt, kh nu mt lm qu b ng nc, thtqu xm en, v qu mt mu vng p, qu khng cn v chua ngt v mithm c trng ca da chin.

Cch x l: qu c ra bng nc sch, sau nhng hoc phun cht ditnm Dowicide A hay Thiabendazole (pha theo nng 7g thuc/lt nc); Cth pha cht dit nm ni trn vi cht to mng bn thm khng c hi (nhBQE 625) ri x l qu va phng trnh nm bnh va trnh qu b tnthng lnh trong thi gian vn chuyn, BQ.

Sau d qu kh t nhin (khong 1 ngy) hoc bng qut thng gi ri tinhnh phn loi qu.

Phn loi:

Trc khi bao gi phi phn loi qu theo chn 2 v theokch c p ngyu cu thi trng. Kch c qu c quy nh nh sau:


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Bng 9. Quy nh v kch c ca da BQ

Ging da Khi lng qu (g)Loi nh (S) Loi trung bnh

(M)Loi to (L)

Da queen Bc B 500 n di700

700 n di1000

10001300

Da queen NamB

700 n di900

900 n di1200

12001500

Da cayenne 1000 n di1300

1300 n di1600

16002000

Bao gi:

BQ vn chuyn i xa trong nc: c th ng qu vo hp carton, thngg, nha hay sttre; mi thng, st cha 20-25 kg qu, bao gi ring tng qu

bng rm, giy mm, xp qu ng thng, cung quay xung di, xen knhau, qu trn chng ln v tr chi qu di; chn, lt k y v thnh thng,hp, st. Thng, hp, st phi c np y chu lc khi xp chng ln nhaukhng b x, bp lm gip nt qu bn trong. Cng c th xp qu nh cch xpcho xut khu .

BQ vn chuyn xut khu: ng qu vo hp carton, hp g hoc nha;xp qu 2 lp nm ngang trong hp, cung quay ra pha thnh hp, chi ngnquay vo trong, mi chi nm xen gia 2 thn qu ca hng i din; gia 2lp qu c tm ngn, gia cc qu c bao gi hoc tm chn thch hp trnhc xt v dch chuyn qu. Mi hp thng xp 6-8-12 qu hay 10-15-20 kgty theo yu cu. Sau khi bao gi phi nhanh chng a da vo kho lnh BQhay xe lnh chuyn ch.

Lm lnh:

Trong

ky thuat bao quan che bien qua

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