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n cng ngh 1

n cng ngh 1

CHNG 1

GII THIU V BIACHNG 2 : MALT I MCH

2.1. GII THIU V MALT I MCH

2.2. K THUT NY MM MALT I MCH2.2.1. LM SCH , PHN LOI V BO QUN I MCH

2.2.2. SN XUT MALT I MCH2.2.2.1. NGM I MCH

2.2.2.2 M MM I MCH

2.2.2.3. SY MALT TI

2.2.2.4. TCH R , LM BNG , NG GI V BO QUN

2.3. NH GI MALTT I MCH2.4. YU CU CHT LNG CA MALT I MCH

CHNG 3 : NGUYN LIU THAY TH MALT I MCH

3.1. NGUYN LIU THAY TH DNG HT

3.1.1. GO V THC T

3.1.2. NG

3.1.3. LA M

3.2. NGUYN LIU THAY TH DNG NG

3.2.1. NG MA V NG C CI

3.2.2. NG THU PHN

3.2.3. INVERTAZA

3.2.4. XIRO TINH BT

CHNG 4 : HOA HOUBLON

4.1. C TNH THC VT

4.2. THU HI, S CH V BO QUN HOUBLON4.2.1. THU HI

4.2.2. SY HOUBLON

4.2.3. BO QUN HOA HOUBLON

4.3. THNH PHN HO HC CA HOUBLON

4.3.1. CHT NG

4.3.2. TINH DU THM4.3.3. POLYPHNOL4.4. CH PHM HOUBLON

4.5. YU CU CA HOA HOUBLON

CHNG 5 : NC5.1. CHT LNG NC5.2. PHNG PHP X L NC5.3. CI TO THNH PHN SINH HC CA NCCHNG 6:KT LUNCHNG 1

GII THIU V BIABia l sn phm thc phm, thuc loi ung c cn thp, thu nhn bng cch ln men ru nhit thp. Bia c tnh cm quan rt hp dn con ngi: hng thm c trng, c v ng du, lp bt trng mn, hm lng CO2 kh cao gip con ngi gii kht khi ta ung. Ngoi ra, bia l th ung c dinh dng v tiu ho cao.V bia c ru nh v c tnh gii kht cao c nhiu ngi a chung. C nhiu nc mc sn xut v tiu th bia l 140-160 lt/nm cho mt u ngi, nc ta mc ny khong 3-5lt.Thnh phn ca bia gm c: 80-90% nc, 1,5-7% cn, 3-10% cht ha tan, 0,3-0,4 CO2. Cht ha tan ch yu l hidratcacbon, cc protein v sn phm thy phn ca n, cc cht khong, mt s axit hu c, cc axitamin, cc cht ng v thm ca hoa houblon.c im gy sng khoi v gy say ca bia l do etanol gy ra. Hng thm v v ng l do houblon v cc sn phm c to ra khi nguyn liu c sy trong l cng nh thnh phn thm to ra trong qu trnh ln men. Gi tr dinh dng ca bia l do hm lng cc cht keo ho tan khng ln men. Hiu qu gii kht l do CO2.Nguyn liu sn xut bia gm 4 loi c bn: malt i mch, hoa houblon, nc, ngoi ra phi k n l nguyn liu thay th. Trong malt i mch l i mch thc qua m mm, sy kh, cc loi ng cc khc nh: la go, la m, ng...v cc sn phm t chng c th dng thay th malt i mch, n c gi l nguyn liu thay th. Hoa houblon l loi hoa c un si vi dch ng trc khi ln men trch li cc cht to v ng c trng cho bia. Nc l thnh phn chim lng ln nht trong sn phm, nc c dng trong nhiu mc ch khc nhau trong nh my bia. Trong ti ny ta ch quan tm n malt i mch, nguyn liu thay th malt v hoa houblon.S cng ngh sn xut bia:

CHNG 2

MALT I MCH

2.1 Gii thiu v malt i mch- Malt l nguyn liu chnh nu bia, l sn phm c ch bin vi cc loi ht ho tho nh: i mch, thc, ng... Sau cho ny mm iu kin nhn to v sy n m nht nh vi nhng iu kin bt buc.

- Malt l mt loi bn thnh phm nhng rt giu cht dinh dng: cha 16-18% cc cht thp phn t d ho tan, ch yu l ng n gin, dextrin bc thp, cc axit amin, cc cht khong, cc vitamin v c bit c h enzim proteaza v amylaza.

- Malt c th dng ch bin cc loi thc phm c cht lng cao nh bt dinh dng cho tr em, cc loi ung tng hp cho ngi gi v ph n c thai.- Malt dng lm tc nhn dch ho trong cng ngh sn xut ru cn t tinh bt, lm tc nhn ng ho trong sn xut ko mch nha... Nhng cng dng ln nht ca malt l dng sn xut cc loi ung c cn thp.

- Malt i mch l nguyn liu chnh sn xut cc loi bia. Qu trnh quan trng nht m qua ht i mch tr thnh ht malt l s ny mm. Qu trnh ny mm l hot ho, tch lu v khi lng v hot lc ca h enzim c trong ht i mch. H enzim l ng lc ch yu phn ct cc hp cht cao phn t trong ni nh thnh cc sn phm thp phn t ho tan bn vng vo nc tr thnh cht chit ca dch ng.

2.2K thut ny mm ht i mch

2.2.1 Lm sch , phn loi v bo qun i mch

Mc ch:

- i mch nhp vo nh my cn cha nhiu tp cht nh cc loi ht v, rc v nhiu tp cht khc. V vy trc khi a vo xilo d tr ht phi c lm sch v phn loi chn loi tt nht, trng lng trung bnh 40-50g/1000 ht, ht i mch cha trn 17% m.

- Dy chuyn lm sch thng gm cc loi my sau c b tr thnh dy chuyn lin tip nhau: my qut sng, my tch v kim loi, my chn ht v cui cng l my phn loi.- trnh h hng, khi bo qun i mch cn phi sy i mch nhit 40-450C n khi m cn 10-12%, ch khng sy qu m trong ht cn di 10%, v nh vy s mt kh nng sng ca ht. Sau khi sy c th gi i mch trong kho vi tun, tt nht l sau 3 tun nn chuyn sang c s ch bin malt.

Ch : Trong qu trnh bo qun cn ch nh k thng gi u khi ht, n nh nhit khi ht v kho, m bo m ht khng c vt qu 15%, chng vi sinh vt v cn trng gy hi.2.2.2 Sn xut malt i mch Cc cng ngh sn xut malt gm 2 bc c bn: sn xut malt ti v sn xut malt thnh phm

Bc 1 gm hai giai on: ngm i mch v m mm i mch

Bc 2 gm hai giai on: sy malt ti v tch r, lm bng, ng gi v bo qun.

S sn xut malt i mch

Thi gian

Ht i mchMc ch

Khong vi gi

Lm sch

Loi b rc bn v ht gy v

Khong 2 ngy

Ngm ht

kch hot ht ny mm

Khong 4-5 ngy

m mm

Ht c tao iu kin ny mm

Khong 24-48h

Sy

Qu trnh ny mm ngng li v

m gim dn

Malt

2.2.2.1 Giai on ngm i mch

- Ngm i mch l qu trnh u tin v rt quan trng, n nh hng trc tip n thi gian m mm, hao ph cht kh trong qu trnh sn xut malt, chi phi cht lng malt thnh phm.- Phng php thng dng nht thng c thc hin l lm t bng nc v bng khng kh.

Mc ch : Loi b nhng ht lp, cc tp cht... m trong qu trnh lm sch v phn loi cha b ra khi khi ht.

Ra sch bi v mt s vi sinh vt, cn trng bm trn ht, ng thi c bin php st trng ton b khi ht bng cch a vo nc ngm cc ho cht.

To iu kin ht ht thm mt lng nc t do, sao cho lng m t 43-45% qu trnh m mm sau ny c tin hnh bnh thng.-Trong qu trnh ngm ht cn thay nc ra sch nht v mi, c th dng cht st khun nh thuc tm, nc oxy gi... v kch thch t ny mm. Tc lm t ph thuc vo kch c ca ht v kch c ca ht cng ln th thi gian lm t cng di.

Tin hnh: Ngm ht trong b hoc thng chuyn dng. Trong qu trnh ngm, m ht c nng t 11-13% ln n 43-45%, nhit ngm ht tt nht 12-170C. Thi gian ngm ph thuc vo nhit nc ngm, kch thc ht, ging i mch v hm lng protein.+ i mch trong kho cha m thp, nc trong ht ch l nc lin kt, ch duy tr kh nng sng ca ht. Khi tng m th trong ht xut hin nc t do, nc t do thc y cc qu trnh sinh ho lin quan n hot ng sng ca mm, thc y qu trnh h hp v hot ho enzim trong ht. Tuy nhin, m ht tng lm tiu hao mt t hyratcacbon do qu trnh h hp ca ht, mt phn nh cc cht to nn v ht b ho tan, nc cn ho tan mt t ng, nit v mui khong. + Th tch v khi lng ca ht sau khi lm t tng trung bnh trn 45%

+ Mc lm t: ht i mch cn ngm nc khng qu mc so vi m ngm t t khi ht ny mm t nhin rung v nu xy ra th n nh hng xu: lp v trong ca ht b ph, tnh thm thu ca n b tn tht, mui t nc thm vo ht lm cht mm .

Yu cu k thut:

- Nhit nc ngm: 12-170C

- Thi gian ngm: 30-48h

- Thng xuyn cung cp O2 cho ht h hp, cn o trn khi ht v thi khng kh y CO2 ra khi khi ht.

2.2.2.2 m mm i mch

Mc ch: To iu kin v nhit v m ca mi trng phi pht trin. S pht trin ca phi l ng lc dn n mc tiu chnh l hot ho v tch lu enzim.1.Chuyn i trng thi ca h enzim t trng thi ngh sang trng thi hot ng, tch lu chng v khi lng v tng cng nng lc xc tc ca chng.

2.To v duy tr iu kin thun li h enzim thy phn sau khi gii phng khi trng thi lin kt ng thi vi vic tng cng v khi lng v cng lc xc tc, chng s phn ct mt lng ng k cc cht dinh dng cao phn t thnh cc sn phm thp phn t, ng thi ph v thnh t bo lm cho ht mm ra ...Cc bin i ny nhm mc ch: n giai on ng ho nguyn liu, trong mi trng nhiu nc, ht c nghin nh, khi lng enzim nhiu, cng lc hot ng mnh, cc cht cao phn t trong ht malt c thy phn thnh cc cht thp phn t, ho tan bn vng vo nc v l dch ng s em i ln men to ra bia.Ny mm nhn to khc vi ny mm t nhin v mc ch. Ny mm trong t nhin l ht ny mm phi to c cy non kho c kh nng chng chu cao, cn ny mm nhn to l hot ho v tch lu enzim.

Tin hnh:

- Ht sau khi ngm nc c a vo thit b m mm hoc ti ln sn ximng c dc thot nc (lp ht trn sn khong 20-30cm). Hng ngy phun nc hoc cho ngp nc ra sch mi, ui kh CO2 v gii thot nhit. - Khi ht i mch nhn c lng m, c cung cp oxy v iu kin t0opt th hot ng sng ca ht i mch bt u. Cc cht d tr trong ht trng ln v cc enzim d dng tn cng vo trng thi trng .- Mm bt u pht trin v cn cc cht dinh dng, lc u th s dng cc cht ho tan trong nc v mt lng rt t cht d hp ph c sn ngay trong mm, sau s dng n cc cht d tr cao phn t (ni nh) ca ht nh tinh bt, cht m, cht bo... c enzim chuyn thnh nhng cht ho tan d hp ph. Nhng cht c phn t lng thp v d hp ph ny c khuch tn n mm: Mt phn c mm dng h hp, mt phn dng tng hp tr li nhng cht cao phn t trong trong thnh phn m ca r v ca l mm.

Nh vy giai on m mm, trong ht i mch xy ra 2 qu trnh:+ Qu trnh phn gii cht hu c thp phn t to ra nng lng cung cp cho hot ng sng ca t bo ng thi thc hin qu trnh sinh tng hp t bo cy non, xy ra phi. Qu trnh ny bt li v hao tn cht kh.+ Qu trnh phn ct cc hp cht cao phn t thnh cc hp cht thp phn t d ho tan, xy ra nhng khu vc cn li ca ht. y l mc tiu cn t c.

Trong thi gian ny phc h enzim ca ht c chuyn sang dng hot ng thy phn cc cht trong ni nh vo dch ng trong nu bia sau ny.i vi i mch, mm c hnh thnh t phi, 8-9 ngy mi nh ra ngoi ht, r m ra ngoi v.S ny mm kt thc khi phn bn trong ca ht tr nn ti xp, r di 1,5-2 ln so vi chiu di ca ht v mm mc bn trong gn ht chiu di ca ht.

Yu cu k thut:

- Nhit m mm :15-180C

- m tng i ca mi trng: 98-100%

- Khu vc m mm phi thong, kn nh sng mt tri.

2.2.2.3 Giai on sy malt ti : L qu trnh cng ngh nhm thu nhn bn thnh phm c y tnh cht v tiu chun v cht lng, c bit l tnh cht cm quan .

Mc ch: Lm cho ht kh, d xt b mm r, bo qun c tt, ng thi ht sy c mu v mi thm.+ Sau khi ny mm malt c m 43-45% do phi sy dng qu trnh ny mm bo qun. Qu trnh ny l lm cho sn phm c hng thm v v c trng m ch malt mi c v cng c hnh thnh trong qu trnh sy m thi. + Do qu trnh sy c tin hnh nhit cao nn hu ht cc vi sinh vt bm trn ht hoc b tiu dit hoc chuyn v dng bo t, hn ch kh nng h hng do chng gy ra. + Trong qu trnh sy nhit khi ht tng chm v m cng gim chm. Trong gii phm vi nhit di 400C v m ca ht trn 20% l iu kin l tng cho h enzim thy phn hot ng, cc enzim ny phn ct hp cht cao phn t thnh hp cht thp phn t d ho tan.Trong thi gian sy, malt chu tc ng ca mt s qu trnh vt l, ho sinh, ho hc v sinh l. Nhng thay i l hc: thay i v hm m, th tch, khi lng, mu sc, hng v v. Khu sy malt lm gim hot lc enzim so vi ht mi ny mm khong 30-40%.

Yu cu : + Thi gian sy: 24h (malt vng), 48h (malt thm) nhng khng lm thay i ln thnh phn ho hc ca ht v khng lm tn hi hay git cht enzim trong malt, tu theo ch nhit m malt thu c l vng sng hay malt thm mu .

sn xut malt cho bia sng mu phi cho ht i mch ny mm trong nhng iu kin nhit khng qu 180C v ch ko di 7 ngy.

sn xut malt cho bia thm mu khong 23-25 0C trong 9 ngy.

+ Khi sy malt cn phi t c nhng s thay i ho sinh v ho hc nht nh trong ht malt. Mun t c iu ny cn tin hnh qu trnh sy malt qua 2 giai on: giai on lm mt nc trong malt v giai on sy malt kh. + Sy malt cho m gim t 43-45% xung 3-4% m cn lm thay i mu sc, mi v v thnh phn ho hc ca malt.2.2.2.4 Giai on tch r, lm bng, ng gi v bo qun

- Malt trong thi gian bo qun kho hoc trong xil lun b bi bn. Nguyn nhn l do ma st ca chng trong thi gian vn chuyn hoc xo trn v tr hoc trong qu trnh tch r mt phn cn st li...

- Sau khi sy ht c em xt tch mm r, v r s lm cho bia c v ng v trong qu trnh bo qun d b su mt n hi.- Hao ph cht kh trong qu trnh lm sch v nh bng malt l khong 0,5%.- Malt c bo qun ni kh ro nhit n ho.- Malt sau khi sy, xt b mm r bo qun. Malt c ng gi phi bo qun t nht 15 ngy n nh hot lc enzim sau mi a vo sn xut bia.

2.3 Yu cu cht lng ca malt i mchCht lng ca malt thnh phm c nh gi theo cc du hiu bn ngoi, cc ch s c hc v thnh phn ho hc ca chng.

1. nh gi cm quan :

- Mu sc: Mu sc ca cc ht malt vng phi l mu vng sng, cn ca malt en l mu sm. V ca cc l malt cht lng cao phi c nh.- V v hng: phi c trng cho tng loi khc nhau.- sch: t l cc tp cht, ht gy, v cha trong v 1% tp cht khc.

2. Hot lc enzim :- Th hin qua kh nng ng ho tinh bt >Kh nng ny c biu th bng n v hot lc, l lng tinh bt c th thy phn n maltza v extrin khng phn ng mu vi it bi enzim c trong 1g malt ti 300C trong 1h

Cc ch tiu cht lng ca malt:

T l ht v, gy, dp : 0.5-0.6%Hm m ca ht : 2-5%

Thi gian ng ho : 15-20ph

Hiu sut ho tan: 70-75%

Cng mu : 0.16-0.26ml

Hot lc amylaza :250-300 WKCHNG 3 : NGUYN LIU THAY TH MALT I MCH

h gi thnh sn phm, trong sn xut bia ngi ta s dng mt s nguy liu thay th bt mt phn i mch. Nguyn liu thay th c chia thnh hai nhm: Nhm dng ht v nhm dng ng.3.1. Nguyn liu thay th dng ht

Phn nguyn liu ny ch yu l cung cp tinh bt cng vi malt chuyn thnh dch ng trong qu trnh dch ha.

Cc loi cc dng thay th malt i mch ch yu l go, ng hoc m. Cc loi ht ny thng c s dng trng thi cha m mm v a vo ch bin di dng bt nghin mn, phi trn cng vi bt malt.

Yu cu: Phi chn cc ht c cht lng cao nu bia: ng c lm sch, loi b tp cht, ht lp, khng b mt, b mc. Thc t th nn xt b v tru v go em i nghin nn dng go mi xay xt.3.1.1. La m (ht tiu mch)- Ht tiu mch gn ging ht i mch, c mt im khc l tiu mch khng c lp v tru. V ca tiu mch ch c hai lp: v qu v v ht lin kt cht hn so vi i mch, v ht v ni nh cht hn so vi i mch.- Khi bt tiu mch tip xc vi nc th protein ca n tham gia qu trnh hidrat ho to thnh phc cht keo t, phc cht ny rt dai v do, c th ko thnh si v c gi l gluten. Vi tnh cht qu ny nn tiu mch dng sn xut bnh m hn l s dng trong sn xut bia.- Kh nng trng n cng hn ch, bia s dng la m ch yu c sn xut v s dng ti Bc u.3.1.2. Go v thc t

- Go l loi cc c dng thay th i mch nhiu hn ht. C th s dng bi hai cch:

+ Dng go trc tip ch bin ln vi bt malt

+ Dng thc m mm, c th sy kh hoc dng dng malt ti, ng ho phi hp vi malt i mch theo t l thch hp.

Tuy nhin, nu dng nguyn liu ph dng khng ny mm th kh c th nng cao t l nguyn liu ph ln. S d khng th s dng nguyn liu ph dng khng qua ny mm vi t l cao c l do s enzim trong trong malt khng th xc tin cc qu trnh thu phn v trch li ton b nguyn liu m trong gn mt na l nguyn liu khng ny mm.

Bin php : c 2 cch

Sn xut ch phm enzim, a vo x l nguyn liu.

Cho cc loi ht ca nguyn liu ph ny mm. Cc c s sn xut bia thng s dng cch hai.- Thng s dng thc go c ni nh mu trng c cho mc ch thay th malt trong sn xut bia v chng cha t protein, nhiu tinh bt.- Ht thc bao gm cc b phn: v tru, v qu, v ht, lp alron, ni nh v phi. Trong thnh phn cht kh tinh bt chim 75%, protein : 8%, cn li l cht bo, xenlluloza, cht khong vi hm lng thp hn.+ Ni nh ca go c th l trng trong hay trng c hoc trng trong tng phn. Ht trng trong khc ht trng c bi hm lng protein cao hn, ht chc hoc cng hn. thay th malt i mch ta nn chn loi go c trng c cao hn.- Khi tin hnh m mm v ng ho cn lu cc c im sau:

+ V thc dy v vy thi gian ngm nn ko di n 2-3 ngy, nhit phng nn khng ch 20-230C.

+ ng ho 670C v dch ho 770C.- Qu trnh ch bin malt thc t ch khc nhau cht t vi qu trnh ch bin malt i mch v mc lm t, v nhit v thi gian ny mm.

+Nu mc lm t ca i mch 44-46% th thc t ch khong 40-42%.

+Nhit ny mm thc t c th ln khong 20-230C, i mch t0 ngm 12-170C.

+Thi gian ny mm cng ngn hn so vi i mch, i mch: 30-48h3.1.3. NgThnh phn trong ht ng: v qu, v ht, aloron, phi ng, ni nh (75% khi lng ht)...Theo hnh thi ng c chia thnh : ng rng nga, ng v ng bt, theo mu sc c ng vng v ng trng.Ng c dng thay th malt ch yu l loi trng c v c s dng di dng bt nghin nh.

Nhc im:

- Phi ca chng ln hm lng cht bo nhiu, kh lc v lm gim bn keo cng nh kh nng to bt ca bia. Bin php: Trc khi a vo ch bin dch ng ng phi qua cng on tch phi v v.

Tin hnh:

- Ngm ng ht trong nc m 500C, c cha SO2, thi gian ngm 30-50 pht vi mc ch l lm cho ht mm ra tc phi c nguyn vn (SO2 l tc nhn ngn nga s pht trin ca vi sinh vt, lm cho mng protein b trng ln, b phn r v khch tn vo dung dch) - Tip ng c nghin th tch phi v c a i nghin mn.3.2 Nguyn liu thay th dng ng :3.2.1.ng ma v ng c ci - L nguyn liu cht lng cao, n c a vo s dng dng ht sau khi tinh luyn, vi hm lng saccharoza khng di 98%.

- Sau khi ng ho, thy dch cha cht ho tan ngi ta thm ng saccharoza, c th dng ng knh trng, ng ct nu hoc ng ct vng.- Lng saccharoza a vo thay th khng nn qu 20% so vi lng cht kh c chit ly t malt vo dch ng, nu qu cao n s ph v cn bng tin trnh ln men v s to ra nhiu ru bc cao.3.2.2.ng thy phnThu nhn bng cc thu phn khoai ty hoc tinh bt ng bng axit, lc ri c chn khng.Lng ng thu phn thay th malt : 10-15%

3.2.3.ng invertazaThu nhn bng cc thu phn dung dch 80% ng c ci. Loi ng ny s dng trong sn xut bia en vi mc ch tng cng mu ca sn phm

3.2.4.Xiro tinh btGing nh ng thy phn, xiro tinh bt c thu nhn bng cch thy phn tinh bt khoai ty hoc tinh bt ng bng axit.CHNG 4 :

HOA HOUBLON

Nhiu nc trn th gii trng c cy houblon nh: Cng ha Sc v Slovakia, c, Ba Lan, Anh, Php, B, M. Cng ha Sc v Slovakia c coi l ni trng houblon tt nht th gii v nng sut ln cht lng.4.1 c tnh thc vt

Vai tr: N c tc dng lm ngng kt abumin (lm cho dch bia trong), lm c ch s pht trin ca vi sinh vt, lm tng kh nng to bt v nht l to nn mi thm, v ng c trng ca bia.

c tnh: Cy houblon l loi cy leo lu nm c trng cc c vng n i. Hoa ca houblon c dng sn xut bia, to hng v c bit. Pha bn trong cnh hoa c mt s lng ln cc ht mu vng sng v dnh. - Houblon c tn latinh l Humulus lupulus. c im ca ging cy ny l hoa c v hoa ci sinh ra trn hai cy khc nhau. Trong sn xut bia, ta ch s dng loi hoa ci cha th phn. Nu hoa b th phn th gi tr ca chng gim i nhiu. Do phi tin hnh nh b cy c trong vn hoa houblon. - Khi hoa chn th bn trong cc cnh hoa, c bit l nh hoa xut hin ht mu vng ng rt do gi l lupulin - phn gi tr nht ca hoa, nu hoa chuyn sang mu g hoc mu cnh gin th cht lng ca chng gim n 50%.- Ht c cht thm, cc cht c v ng c trng, nh bia c v ng d chu, c hng thm, bt lu tan.

- Vit Nam do iu kin t nhin cha ph hp nn vic trng khng em li kt qu kh quan.

- Hoa houblon l loi thc vt a m, rt ph hp vi t ph sa, t mn,t ct pha vi PH =7

- S lng hoa ph thuc vo chng ging, iu kin canh tc, gieo trng v iu kin kh hu.- Hoa pht trin tt vng Trung u v Bc M. Ngi ta tha nhn rng, hoa ny trng Tip khc c c cht lng ng hng u th gii.

4.2 Thu hi, s ch v bo qun houblon

4.2.1.Thu hi

- Houblon c thu hi khi t chn k thut, nu khng thu hoch ng lc th n s chuyn sang thi k chn sinh l, lc ny ht lupulin ri rng, hoa mt phn gi tr nht.- Cy houblon thuc thc vt thn g, mnh, cao 2-3m, c khi n 5-6m. Chng c trng theo lung.

- Vic thu hi c th thc hin th cng hoc c gii bng loi my chuyn dng.+ Nu hi th cng th phi s dng chic thang t hnh, chy gia hai lung. Ngi cng nhn ng trn thang v ln lt ct tng gi.

+ Hi t ng: c nhiu loi my, chng khc nhau v cu to v nguyn tc hot ng. Cc my ny c th x c nhng gi hoa thn cy v nhng cnh nh c hoa, sau phn loai bng kh ng hc.

4.2.2.Sy houblon

Hoa houblon c th em dng dng ti nhng bo qun c lu v d vn chuyn ta phi sy kh chng n hm m khong 11%.

Hoa ti mi thu hi thng cha m 70-75%, vi m ny khng th bo qun c lu do ngi ta phi tin hnh sy.Thng thng hoa c em sy n m khong 10-13%. C hai phng php sy:

- Sy t nhin: ri hoa thnh lp mng 5-8cm, ko di 2-3 tun.

- Sy cng bc: c thc hin bng kh nng 400C.

4.2.3.Bo qun hoa houblon

- Hoa sau khi sy xong c tin hnh phn loi li v hoa rt gin v vy phi gi trong phng c m tng i 85-90%, t0 =20-300C trong 10-15 ngy.

Sau , ngi ta xng hi bng SO2 hn ch s oxy ho v pht trin ca vi sinh vt. Ri dng my p c p sut cao p cht thnh bnh, thnh nhng thi hnh tr... Hoa thnh phm c ng gi kn bng vt liu cch m a i bo qun.

- Sau khi hoa c ng gi th em bo qun ni kh ro, nhit thp v khng c nh sng mt tri. Nhiu nc bo qun hoa trong mi trng CO2 hoc N2 cho kt qu tt nhng t tin.

- bo qun hoa lu hn, ngi ta c th ch bin hoa thnh cao hoa: Hoa houblon va sy xong c cho vo cn 96% trch li, ri c c dch trch li thnh cao, thi gian bo qun ko di 3-4 nm.

- L thnh phn quan trng khng th thiu trong cng ngh sn xut bia. N c tc dng nh mt cht lm trong, v n kt ta protein trong dch hm, lm thay i c tnh ca dch hm to ra hng thm v v ng c bit. Hm lng protein cha trong houblon lm tng kh nng to bt trong bia.4.3.Thnh phn ho hc ca hoa houblon

Thnh phn ho hc ca hoa houblon ph thuc vo chng ging, iu kin kh hu, t ai v k thut canh tc.Gm c:

- Nc:

11-13;xelluloza:

12-14

- Cht ng:

15-21;cht khong:5-8

- Polyphenol:2,5-6;tinh du thm:0,3-1

- Protein:

15-21;cc hp cht khc:26-28Trong cc cu t trn th cht ng c gi tr nht, tip n l tinh du thm v polyphenol

4.3.1.Cht ng:

Vai tr :Cht ng c vai tr quan trng trong sn xut bia- Cht ng lm cho bia c v ng du, to ra c tnh cm quan rt c bit ca bia.

- Cht ng gip cho bia gi bt lu hn do kh nng to sc cng b mt cao.

-Vi mt nng kh thp n cng c th c ch mnh s pht trin ca vi sinh vt gp phn to tnh khng khun cho sn phm.

Thnh phn ho hc : Cht ng trong hoa houblon gm nhiu hp cht. Trong :- -axit ng: 6-9% _y l thnh phn c gi tr nht trong cht ng ca hoa houblon.Kh nng ho tan ca n vo nc khong 500mg/l, trong dch ng th t hn nhng trong bia th khng ng k.

+Trong cng on un hoa , -axit ng bin i thnh cc ng phn c kh nng ho tan tt hn v ng cao hn.

- -axit ng: 3-4%_t ho tan trong nc nhng tnh khng khun mnh hn. Cc cht ng c th b bin i di tc dng ca nh sng to v xu cho sn phm.- Nha mm: 5-6%_kh nng ho tan vo nha mm cao hn -axit ng v vy n to ra v ng kh ln cho bia. y l hp phn rt c gi tr ca cht ng.

- Nha cng: 1-2%_Chng khng ho tan vo nc v dch ng. y l hp phn khng c gi tr trong cng ngh sn xut bia.4.3.2 Tinh du thm

- L cht lng trong sut mu vng nht, khng mu, c mi thm rt mnh

- Tinh du thm ca hoa houblon ho tan vo dch ng to cho bia c mi thm c trng, nh nhng v d chu.- Thnh phn tinh du thm trong hoa rt phc tp, c n 103 hp cht khc nhau. Trong phn ln l terpen, ru, xeton, aldehyde, este, axit hu c. Nhm cc hp cht chim khi lng nhiu nht trong thnh phn tinh du thm l hydratcacbon (75%).- Trong thi gian un si dch ng vi hoa houblon c n 98% lng tinh du thm bay ra ngoi theo hi nc, ch cn 2% tn ti trong bia.

4.3.3.Polyphenol

- Vai tr : c dng kt lng v loi b cc hp cht protid cao phn t ra khi dch ng nhm hn ch kh nng kt t c bia sau ny, lm n nh thnh phn v tng bn keo ca bia.- Nhm flavonoid: flavan, flavon, flavanol... .Nhm flavonoid d dng thc hin phn ng ngng t to thnh oligome v d dng polyme ho to thnh polyme. Oligome d dng kt hp vi vi protein cao phn t to thnh cc phc cht khng ho tan, nhng phenol c tnh cht nh vy c gi l tanin.

+ Cht tanin lm ngng kt, ng vn abumin trong giai on nu dch ng, nhiu loi tanin c v ng cht. V mt cng ngh phi tn n cht tanin v n to ra bn sinh hc, to v gi bt tt, nh hnh v ng v hng thm cho bia.4.4. Ch phm houblon

S dng hoa nguyn cnh trong sn xut bia c u v nhc im sau:- u: Bo ton c cht lng

- Nhc: Th tch cng knh, kh bo qun.

Do trong sn xut bia ngi ta ch bin hoa cnh v cc b phn ca n thnh dng bn thnh phm, gi l ch phm houblon s dung thun tin hn

4.5.Yu cu ca hoa houblon- Hoa houblon lm cho bia c v ng du, hng thm c trng, lm tng kh nng to v gi bt... Do hoa houblon l nguyn liu khng th thay th c- Trong cng ngh sn xut bia ngi ta thng dng hoa houblon kh, n c bo qun ni kh ro, mt m, trnh nh nng.- Yu cu ca hoa khi thu hi: hm lng lupulin phi t cc i, mu sc ca cnh hoa chuyn t vng xanh sang mu vng, hoc vng - xanh c nh. Khi t n chn k thut, cc cnh hoa phi trng thi ng kn hon ton, do v c tnh n hi ln, hoa ta mi thm rt mnh, rt sc nhng d chu. Ht lupulin phi chuyn sang mu nh kim v trn c ph nhiu bt, mu vng rc.CHNG 5

NC

i vi sn xut bia, nc l nguyn liu khng th thay th c. Nc c dng trong qu trnh nu, pha long dung dch ng ln men. Ngoi ra nc cn dng cho cc qu trnh khc: lm lnh , lm nng, ra dng c, thit b v v sinh khu vc sn xut...Trong phn ny chng ta cp n loi nc c s dng trong dy chuyn cng ngh chnh.

Nc dng trong sn xut bia l nc mm, nu l nc cng cn phi x l qua trao i ion. Nc c st v mn khng dng cho sn xut bia. Nc phi t tiu chun dng cho nc ung, khng c mi v, khng mu, trong sut, khng c mi ca amoniac v kim loi nng.1.Cht lng nc: Nhng ch tiu cht lng quan trng ca nc l cng, PH, hm lng cht kh...

- cng ca nc l hm lng mui canxi v magi ha tan trong . cng l tng hm lng tnh bng miligam ng lng ion canxi v magi trong 1l nc. sn xut bia ngi ta loi 2 loi ion ny ra khi nc, nc s dng trong sn xut bia l nc rt mm, thch hp nht l nc c cng tm thi khong 0,7mg-ng lng/l, nc cng vnh cu khong 0,4-0,7mg- ng lng/l.

- PH trong sn xut bia khong 6,8-7,3

- Lng cht kh l khi lng cht cn cn li khi un bc hi cn ht nc v sy kh 1050C n trng lng khng i. Nu nc cha hm lng st vt qu 0,3mg/l hoc nu hm lng nitrat v nitrit nhiu s km hm s pht trin ca nm men, to v kh chu cho bia.

- S lng cc t bo vi sinh vt khng c cha qu 100 t bo/1lt, trc khun coli khng c qu 3 t bo/1lt

2.Phng php x l nc:- ng t cc hn hp colloit:

Nc sng, nc ging cha nhiu hn hp v c v hu c dng colloit, chng khng c gi li trong h thng lc ct si

Bin php: Tin hnh 3 khu

ng t: dng Al2(SO4)3.18H2O hoc c th dng FeSO4.7H2O

Lc ct: Lc qua ct si

Lm mm: Kt ta ion canxi v magi, dng phng php trao i ion hoc in diC th mm nc bng phng php kt ta cc ion canxi v magi hoc bng phng php trao i ion... Nguyn tc ca phng php trao i ion l thay th mt s ion ca mui trong nc bng mt ion khc.3. Ci to thnh phn sinh hc ca nc:Mc ch: L dit vi sinh vt c trong nc lm cho nc sch v phng din vi sinh vt. C cc phng php x l sau:3.1. Phng php vt l

Lc qua thit b siu lc. Loi ny c th gi li tt c t bo vi sinh vt k c bo t ca chng.Tuy nhin, gi thnh loi my ny rt t.

3.2. Phng php ha lChiu tia t ngoi v x l bng siu m. Tuy nhin, gi c thit b t, dit khun thp.

3.3. Phng php ha hc

L phng php r tin, d thao tc, u t thit b t

Nguyn tc: Dng Clo, oxi hoc mt s ion kim loi tc ng trc tip ln t bo vi sinh vt v ph hy chng. KT LUN

Ngy nay bia c sn xut khp th gii v chim v tr ng k trong s cc ngnh cng nghip c tng sn lng v danh thu ln. V bia c nhng ch li nht nh nn n c nhiu ngi a chung, nhng lm dng qu mc n s nh hng n sc khe con ngi. bia c c hng thm, mi v v ngon th vn nguyn liu gp phn rt quan trng.

Trong qu trnh lm n, mc d c gng thu thp nhiu ti liu bi lm c y hn nhng chc khng trnh nhng thiu st. Cc thng s ca cc sch tuy c khc nhau cht t nn em ly cc thng s gn y nht. Mong rng s gp ca thy c s gip em lm n sau c tt hn.

Trong qu trnh tm hiu cc sch tham kho, em hc hi c nhiu iu, c bit v nguyn liu sn xut bia. TI LIU THAM KHO

1. PGS.TS.Hong nh Ho. Cng ngh sn xut malt v bia. NXB Khoa hc v k thut, 20042. L Bch Tuyt. Cc qu trnh cng ngh c bn trong sn xut thc phm3. PGS.PTS.Lng c Phm, Cng ngh vi sinh vt, 1997

4. GS.PTS. Nguyn nh Quyn, Gio trnh vi sinh vt hc cng nghip. Nh xut bn khoa hc v k thut, 19995. H Xng. Cng ngh sn xut bia. Nh xut bn khoa hc v k thut, 1992

Nghin

Nguyn liu chnh: Thc malt, go, ng

Nu

(ng ho)

Nu

vi hoa

Lc

Lm lnh dch

Ln men chnh

Men ging Saccharomyces

B men

Ln men ph

Bo ha CO2

Lc

CO2

ng chai

Chai

Ra chai

St Khun

Bia chai

Bia hi thnh phm

Ra

Cp lnh

Chai

Trang 1

2Trang 3GVHD: PHAN TH BCH NGC

SVTH: ON NGUYN LY NA

_1236168326.unknown

_1237814676.unknown

_1238349070.unknown

_1238349446.unknown

_1239471347.unknown

_1239472080.unknown

_1239562436.unknown

_1238349777.unknown

_1238349086.unknown

_1237817342.unknown

_1237817860.unknown

_1237818604.unknown

_1237817247.unknown

_1236880974.unknown

_1237800216.unknown

_1237811737.unknown

_1237811886.unknown

_1237813812.unknown

_1237811807.unknown

_1237800422.unknown

_1237800572.unknown

_1236881471.unknown

_1236918098.unknown

_1236918397.unknown

_1236881550.unknown

_1236881042.unknown

_1236201736.unknown

_1236258371.unknown

_1236258498.unknown

_1236201758.unknown

_1236169513.unknown

_1236197834.unknown

_1236168346.unknown

_1236112886.unknown

_1236112914.unknown

_1236112925.unknown

_1236112903.unknown

_1236112623.unknown

_1236112863.unknown

_1236112505.unknown