MFR PAPER 1037

Scientists study menhaden fish solubles and fish oils as nutrient supplements in mushroom culture .

Mushroom Culture : A New Potential for Fishery Products

JOH N H. GREEN

ABSTRAC T

This paper describes research sponsored by the National Marine Fisheries Service. NOAA. and heing done w the Mllshroom R esearch Center, Pennsylvania S((/te Vnil'ersity, to explore menhaden (Brevoo rt ia tyra nnus) fish solubles and fish oils as nutrient supplements in mushroom cultllre. Fish solubles Ivere success­fully substituted for other organic nitrogen supplements commonly used in mush­room composting and subsequel1l lIlushroom culture. These experilllents, per­formed in 1971-1972, indicated th(/( in certain situatiollS larger lIlushroolllS were produced \l'hen combinations offish soluhle.\' and other organic nitrogen supplements \l'ere used. Currently under inl'estigwion ill 1973-1974 is the use (~f fish oils, substituted for polyunsatur£lted vegerable oils, to stimulate increased yields of nlushroom.l. A hrief dl'scriptioll of IIlllshroom culti\'({tion is gil'ell \l'ith emphasis on nitrogen supplemen(({tioll of composts and polyunsallirated oil stimulation for increased mushroom yields.

These inl'estigations of menhaden fish solubles and fish oil could open lip nell' /llarkets for these products. A t the same time, they could offer the mushroom grower nell' and inexpensil'e sources or nitrogell .luppleml'lIts or nutril'lIt stilllU­lallts. Both industril'S could bellefit ji-om the.\·1' applic({(iolls (~rfishl'r)' products or by-products. An I'co ll omic prospectus is gil'ell of this potential market lI'ith estimations of the maximum I'oit ll nes.

INTRODUCTION

Mushrooms (basid io mycetes) a re fun gi whi ch ma n has used fo r food over countl ess centuri es. T h rough inte res ts in sin gle ce ll prote in produ c­ti on. we became aware o f th e poss ibilit y th a t fi she ry produ cts and by- produ cts mi ght be utili zed in mushroom cul ­ture . Th e cente rs of mushroom culture in th e United States a re located prima r­il y In th e no rth e rn Mid-Atl anti c

Sta tes. mai nl y in southeastern Penn­sy lva ni a. T he re is a small er but ex­pandi ng industry concentrated in the Wes t Coast States and the Great Lakes Region . mainl y in Mich igan and Ohio. Severa l o th er states. incl uding the coas ta l sta tes of Massachusetts. Virgin ia. Georgia. and Florida. pro­du ce mu sh rooms on a scale smaller th a n th e above-mentioned areas. T he mush room ind ustry in the U n i ted Sta tes is growin g.

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Figure 1.-Mushrooms growing on compost. ( Photograph, courtesy 01 Pennsylvania State University.j

The College Park Fishery Products Technology Laboratory became in­terested in exploring the feasibility of usi ng fishery products and by-products In mushroom culture. Helpful in­formation and guidance on the require­ments of mushroom culture were initially received from Drs . James P. San Antonio and Claude Fordyce, Jr.. of the U.S . Department of Agri­culture Mushroom Research Group. Beltsville. Md. (Dr. Fordyce is now with the L. F. Lambert Spawn Com­pany . Coatesville, Pa.l . A contract was made later with Dr. Lee C. Schisler of the Mushroom Research Center at the Pennsylvania State University, and his expertise was put to work to explore the feasibility of using fish sol ubles as an organic ni trogen sup­plement in making compost for mush­room culture and fish oil as a stimu­lant for increased mushroom yield. The initial results of these experiments look promising and although further experimentation will have to be done. there are promises of new potential

John H. Green is a member of the staff of the College Park Fishery Products Technology Laboratory, National Marine Fisheries Service, NOAA, Col­lege Park, MD 20740.

Figure 2.-Large pile of composl being formed . (Photograph , courtesy of Butler County Mushroom Farms, Inc.)

uses for fish oils. fish solubles. and perhaps other fishery byproducts or condensed waste effluents as nutrient supplements in (Green et al .. Patton. 1973),

mushroom culture 1973: Schisler and

COMPOSTING AND NITROGEN SUPPLEMENTS

Mushrooms are grown commercially on the traditional horse manure com­post. In more recent decades a "syn­thetic" mushroom compost has been developed consisting of corn cobs and hay. Horse manure compost is still being used by the majority of the mushroom growers and "synthetic"

Figure 3.-Experimental pile of compost, con­taining fishery byproducts, at Pennsylvania State University.

compost is used by about 40 percent of thi~ industry. There is now a gro'A-­ing interest by many concerns to grow mushrooms on compo~ted 'A-aste such as city garbage. agricultural waste. and re~idue from various industrial processes. Disposal of waste by com­posting followed by mushroom culture could help solve some of the solid 'A- aste disposal problems . A I though the technique is largel y e.\.pcri mental now . the future ma y see more of this in actual production. 0 matter ~ hich type of compost is used. the ingredients of gyp um for te:>..ture and one or more types of organic ni trogen sources are mi.\.ed in at the initiation of com­posting.

In order to assure the good com­posting which is necessary for good mushroom production . the grower must raise the initial nitrogen content of the compost from approximately 0.8-1.2 percent to 1.5-1.7 percent on a dry weight basis . To do this. he adds one or more organic nitrogen sources. such as dried chicken manure (2-6 percent N). dried brewers grains H percent Nl. cottonseed meal (7.0 per­cent Nl. cocoa bean hu lls (3 percent N). and other materi als contai ni ng organic nitrogen. Chicken manure varies in its n itroge n co nte nt and presents problems to th e mush room grower in terms of consistency. proper mixing. and occasional excess am­monia fo r mat io n duri ng composti ng. Excess ammonia inh ibits mush room grow th. Inorgan ic nit rogen or sm all organic mo lecul es. such as urea. are usuall y less ex pensive bu t th ey

28

often leach out of the com post pil e d uri ng wate ri ng ope rations. In addi ­tion. inorganic n itrogen does no t give result~ as good as those of o rga ni c nitrogen. hencc the desire for o rga ni c nitrogen substances by th e m ush­room grower. Their supp li es of des ired nitrogen supp lements are becom in g more expensive as the demand fo r these materials increases for this and other uses. There are compan ies tha t supply mushroom growers ~ ith a mixture of dried. fonifled organ ic nitrogen substances of guaranteed nitrogen consistency. We became in­terested in the possibility that fish solubles . 'A-hich is quite consistent in nitrogen. 5 percent. migh t be used for this purpose . A contract was made 'A-ith Dr . Schisler to explore the use of menhaden fish solubles as a nitrogen

Figure 4.-Fill ing Irays wilh experimental com­posl containing polyunsaturated oils at Pennsyl­van i a State University.

supp lement in mu sh roo m co mpos tin g. T he ni troge n su ppl e me nt d oes no t

directly supply nu t ri ents to th e mush­room. N it roge n a nd oth e r suppl eme nts are importa n t in suppo rtin g th e mi c ro ­bia l growt h of the compos t process whic h must go o n pri o r to pl a ntin g with mush roo m spaw n . The co mp ost­ing is ca r ried o n by a va ri ety of mi c ro­organ isms. in cludin g th e rm ophili c bacteria. ac tin o mycetes. a nd fun gi. To furt he r e ncourage thi s co mpos t

Figure S.-Professional supervision and main­tenance of mushroom spawn cultures which are used to inoculate new beds or trays 01 compost. (Photograph , courtesy 01 Butler County Mush­room Farms , Inc .)

microbia l growth , the hu ge pil es of compost ingredients are periodically watered and aerated by turning to achieve good aerobic growth. Temper­at ures of the compost reach as high as 165-175 0 F. Wh en the peaks of rapid

microb ia l growth a nd temperature are reached. which ends Ph ase I of com­pos tin g. the hot. raw compost is placed in beds or trays in side mushroom ho uses which are then steamed to con­tinu e Phase II of composting at a low­er temperature ( I ~O-135° F) to fina ll y conditi on compost. The heat generated during Phase II and supplemental steam are utilized to pasteurize the mushroom house by killin g off insects. nematodes. and competing fungi.

The entire composting operation takes from ~ to 3 weeks. Good aerobic growth of these composting micro­organi sms yie lds a biologically stable compost of mushrooms . which are rea ll y slow growing fungi. Poor com­posti ng produces poor or no yields of mushrooms . Therefore. the compost ingredients a nd procedures are very important in order to get good yie lds of mush rooms .

Wh en composting is completed. th e trays or beds of compost are

Figure 5.-Typical mushroom growing houses on a Pennsylvania farm . (Photograph, courtesy of U.S. Department 01 Agriculture .)

planted with a pure cu lture of mush ­room spawn. The newly spawned com­post is a ll owed to develop mycelium growt h and then it is covered wi th a thin layer. usually topsoi l o r peat called casing. This casing layer is necessary in order for the mycelium growth to produce fruiting bodies (mushrooms). Sometimes nutri ents are added to the mushroom cu ltures at the time of casing. Th is is referred to in the trade as SACing (Supp le­mentation At Casing). In the future. some of the fishery products and by­products might find uses in SACing. Experi mentation would be needed to show this application.

In the United States the only mush­room species grown of commercial importance is Agariclis bisporul, however. there are many different strains which are grown for various purposes. I n the Eastern and M id­western States, fresh mush rooms sold in markets are usually white strains. The faster and more abu ndant growi ng cream or brown strai ns are grown for canning because either white. cream. or brown essentially are the same color in the final canned product. In the West Coast States. only the cream

Figure 7.-Mushroom spawn (mycelium grown on sterilized, sprouted cereal grains) being spread on compost. (Photograph , courtesy 01 U.S. Department 01 Agriculture .)

llr brll\\ 11 ,tl alil" arc grll\\ 11 "l1d u,cd for cithcr thc Irc,h I11dll-.cl II "dc llr

callilcd prnduci\. SOl11e gelleral re\crCI1CC, In Illll,h

rool11 culturc arc thc Ill llll\\Il1g: 1 dill-

Figure B.-Thin layer of casing (top sOil or peal) being placed over tray of spawned compost t" enhance the production of fruiting bodies (mushrooms). (Photograph, courtesy 01 Buller r:ounty Mushroom Farms, Inc.)

Figure g.-Stacked trays of growing mush­rooms inside mushroom house (Photograph, courtesy of U.S. Department of Agriculture.)

hcrl (1')h71. Illll ki ( Olllll\ \111 ,111110111 1 "1111, 111C. ( I 'lh ' ») \ll d,lllgCI (1'J7!)), dl1d K IIlIU' ( I tl7 I) I "h ,olllhk, h,,\ e hccll d~',c"hcd 11\ \O"IC' cl .Ii (1')7!). 1'J7 \ l.

THE EXPERIMENT

1)1 \Lill,lu dlld 11" """t.llli \11 I IHlI11.I' 1',,111111 Llll1dUlIcd .111 ~' p~11

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1 Reference 10 trade name does not mply endorsement by the Nallonal Marone F,srer es Service NOAA

Figure lO.-Expenmenta ' trayl of mUlhrooml being chec ked l or Yleld l (Pholograph courlesy 01 Buller Counly MUlhroom F rma Inc)

Illlllli er l f mu hr )(11ll \t:rc made f r l.ILh I: penmt:nl.11 Ll)lllhtil'n ..loll ub-ICLlLd III I, II tll:.tI L I In

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Idhll: nd::! It I llhcncdln IJhlc I (h,,1 III 1111 I IIUdl,on \,hell h h ,Iubk rlpl,ILL hrL\\<.:f .!ram ( Im-

p" I I' 2 ..1m! ) I he \ Il'id are IgnlllL.tnlh Ie H,)\'t:\cr h h 'llIhle .til rLpl.tl..1.: \LlIl (e 1mI' 0 \)

,md ~I\e Ll.jll,tI re ult \n "1It:r1.: Iln~

,'h ef\,llnlll I nuJl III I.lble 2 Ihat \\hen II h '-.'Jluhk ,Ire III ("01 I)" I l'll \\lIh hrc\\cr, gr.1I1l (( ,)mp,' I " l' ~).

the mu hrll"1ll \\c're 1~lllli~ Inlh

Figure 11 .-Plcklng mushrooms trimming butts (wasle) and sort.ng Into ba.kel. ( Photo-graph courtesy 0' Butler County Mushroom Farms . Inc.)

Figure 12 .-Mushrooms cultured on compost (upper right) , freshly picked and Irimmed (cenler) and trim wasle (lower left) . (Pholograph , courlesy of Pennsylvania Slate University.)

large r : also in the white strain (Com ­post N o.2) even th ough the total y ield was less in the latt er. Dr . Schi sler and Mr. Patt on are prepar­in g a repo rt of th ese results.

L arge r sized mushrooms would be of econo ll1i c import ance to th e mush­room gr owe r. T he larger sized mush­room would brin g a better price in th e m arket and th ey woul d also re­prese nt less pi cki ng ti me for the same har vest y ield . H and pi ck in g is one of the remaini ng costl y operati ons fo r mushroom growe rs. Many o th er opera t ion invol ved in mu shroom growin g have been mechanized . but

Table 1.-Relative yields 01 mushrooms grown on horse manure-straw-gypsum mixture compost conlaining fish solubles as nilrogen supplemenl and compared 10 conlrol.

Nitrogen White Cream supplement' straln 2 straln 3

1 . Brewers grain Control Control Acto 88

2. Fish solubles Less'

Less I Acto 88

3. Brewers grain Equal Equal Fish solubles

4 Fish solubles Equal Less I

I Nitrogen supplements were added so that each supplement contributed 50 percent 01 the N. The total N In all composts IS the same

:! White strains are used for fresh market mush­rooms In the Eastern states.

3 C ream strains usually grow faster . Yields are greater . and they are used for commercial canning.

, Very sign i ficant differences (P<O.Ol)

Table 2. -Relative size 01 mushrooms grown on horse manure-straw-gypsum mixture com­post containing lish solubles as nitrogen sup­plement and compared to control.

Nitrogen Wh,te Cream supplement' strain:! strain;)

1. Brewers grain Control Control Acto 88

2 . Fish solubles Larger' Equal Acto 88

3 . Brewe rs g ra in Large r ' Larger' Fi sh so lu b les

4. Fish sol ubles Equal Equal

' Nitrogen supplements we re added so that each supp lement contributed 50 percent of the N. The total N In all composts IS the same.

2 White stra i ns are used for fresh market mush­rOoms In the Eastern states .

3 Cream strains usually grow laster , Yields are greate r . and they are used for commercial canning

4 Very slgnllicant d ifferences (P < 0 .01) .

the present sy tem found on many mu hroom farms of fixed mu~h room beds stacked inside house can only be p icked by hand. Hence. there is interest in nutrients which will stimu­late larger sized mushrooms.

IN TERMS OF FISH SOLUBLES, OTHER BYPRODUCTS

The amount of nitrogen ~upple­

ment used per ton of compost would vary depending upon the initial con­centrations of nitrogen in th e horse manure. corn cobs. hay. etc. A range of about 6.7-13.2 pounds (dry weight) of nitrogen pcr ton is required to formulate the desired mushroom com­post. This would be the equ i va lent of

135 to 270 pounds of fish 50 lubl e, at 5 percent N. An esti mated 1.200.()()() tons of compost were produced In 1973. based on USDA I\!UShrolll1l Report (1973) citing about 102 1l1i1-li on square feet of mushroom produc tion area for th at year (each 1.000 '4 ft of mushroom growing area ,",ould require abou t I 1-12 tons of compost). This wou ld have required the e4Ut\3-lent of about 80.00 to 160.000 tom of tish solubles for 1973. Assuming the maximum of 160.000 tons at a price of 550/ton (general market prtLe prior to 1973), this ,",ould represent a $8 million market. Bearing in mind that certa in nitrogen supplements. like brewers gra ins. arc desired or

Figure 13.-Fresh mushrooms ready lor slicing and putting into tasty load dishes . (Courtesy , Butler County Mushroom Farms , Inc.)

ll(h~r\, ItI,~ d'ICI..~1l 111dl1UIC 1'1 LI'LII,I hu\b, aiL' rcadlh d\,III.1hk 111 Cl'll.llll ar~a\, ,tI'll Ihal Ih~ .I11111UI11 1,1 111111'!!l'l1 u\cd dL'r~l1d\ Upllil Ihl' il1lll.d 11111 IIl;l'l1 Cl'111~111 ,,1 Ih~ hl,r'L' 111.111\lIe l'lL Ihl\ l11a,\II11UI11 P"IL'I1II,d 1,'1 II,h \1,llIhl l" cIluld I1l'\~r bl' Ic',tllI~d 11 11" l'\L'I, ~\ell 2~ ~() pelcl'l1l 1,1 Ihl' ",lll11dll' \\ ould rcpl~\l'111 ,I gl",d 11~\\ 111,lIl..l'l r,'r li,h 'llluhk\,

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th.11 b\ prodllc'l \\ nh high II h l't! rl'ldul' \\Luld "rLlb.thh hL .ll".tll tagl'L1U fL'1" 11L1 hrl'I'"' cullllr~

POTENTIAL FOR FISH OILS

Ie\\ \"' ..1' ,1!:!ll. Dr \Lhl ler he!;.11l ~'\p~rtll1l'nl \\ Ilh \Cl!~I, ble L'I, d

nulrt~nl tLl UI ~LLl\ C r~d

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\~gelahk l'li ul'h ,I C,l\tO'l ~Ld ,Ind '0) h~al1 add~d hd Llr~ Ph,1 C II 1'1 "'Ill. potlng ,tIIl1UI.ltcd II1Cn:,I,~J \ lek" III mu,hrllLln h\ '~ 2() r~rccnt Lhl I~r

and PallLln . 1l)7UI Alter Dr \l.hl,kr · 1n\~'llgalll'n llf ahout .1 \c,lr\ .tgo. mushroon' !:!ro" ~r\ hcgan u II1g

\ egetable oi I \1\\ abLlut 12 pncelll of Ihe mushroom, gnl\\ narc rrllduL'l'd on compo,!,> \uppleml'nt~d \\ Ith vegetable olb to Inl'rea\e th~lr \ Il'ld\ It IS e\peLied that ncarl) all l,1 the grov.ers \\ III e\entuall) he u'lng "tI for thiS purpose ~Ince n\h oil\ are more polyunsaturated than Illll,1 vegetable oi Is, e\pen Illenh \\ ere hl" gun to e:\plore menhaden fi,h oil a, a possible stimulant to Incrca,e mw.h· room yields,

The estimation for the consum ptiOIl of polyunsaturated oils as stimulants for increased mushroom production

""ltld bl' ,I Illol IIlllllll III II 7o{J 1""' III "tI 12 ' 1111111"11 ',tll"ll I P'I 'C,II

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, I

CONCLUSION

\i1'lh II 10 ,'"lIlk .Ind II h I'll u'ul" Icpr~ c'Il1 1.:<':1 11 o III 10.. .Id\,mt.t 'C

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II uppl lIIel1l

111111U,II JIldIUI.1i ,I ,lIl'lhk ,nd ulI.IIlI r Ir mll hH 111

LITERATURE CITED

MFR Paper 1037. From Manne FisherIes Rev/ew, Vol 36, No 2, February 7974 CopIes of th,s paper, In lImIted numbers, are avatlable from 083 Techntcal Informa· t,on D,v,s,on , Envlfonmental Science InformatIOn Center, NOAA, WashIngton DC 20235

32