CA1058949A - Process for making food products from whey - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE
Food products such as animal feed are made from whey by mixing the whey with a natural starch and protein-containing product such as a cereal, subjecting the mixture to liquefying of the starch and subsequent hydrolysis thereof to a sugar and converting the sugar into a yeast-protein containing material by fermentation with microorganisms followed by concentrating the fermented product by evaporation and drying it.

Description

1~5139~3 The invent ion relates to a proce~3s :eor using ~Phey to make food products including part~culalrly animal feed.
Whey from the cheese production const itute~ a problem OI
worldwide extent . On one hand the chee~e product ion results in large amountæ o~ a byproduct which is only di~I icult to use and on the ot her h and the by pr od uc t c ont a ins v al u abl e c ompone nt ~ mak ing a discarding a~nd de~3truction OI the whey which still is being practiced in Part~ 0~ the industry as hardly reconcilable with the problem o~
I ighting starvation and pollution OI the environment.
Processes Ior u~ing whey have already beer~ proposed.
Depending on its origin, whey consists of about 4 to 5% lactose and about 0.7% protein. The remainder are salts and ~vaterO Dry whey ~ ~
as additive to animal feeds is obtained by evaporation and drying. ~ ::
The thu~-obtained ~inal product consis1;s of abou1; 11 to 12% protein and about 60 to 65% lactose plus various salts. The making OI this product, however, i5 energy-inten~ilve amd thus rather c:ost ly .
Different po~sibilities for ~ermenting the lactose present ~:
ill the whey are disclo~ed in French patent 2,049,425, British patent 1,383,703, U.S. patent 3,818,109 and German published applications ao 2,403,306 and 2,410,3490 All the~e proc~sse~, however, do not result in a product ~: ;
whieh const itute~ a balanced mltrim~nt or humans or animalsO ~ot even the prote ins present in the products have a balanced spectrum oi amino acids. Insofar a~ the amino acid composition i~; concerned, dry whey appears the preIerable material since it contains adequate amounts oi methionine and ly~ine. However, in view OI the exca~s OI
carbohydrate~3 in the Iorm of lactose, it cannot be considered a high-value f ood product O
Yeasts obtained from whey cultures and complying with the requirements o~ the F.D.A. have a de~iclency in the just-mentioned

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~Q;~8~9 amino acid~ and, because o~ tbeir high ~alt and nucleic acid compo- ~:
nent, cannot be employed as ~c,le nutriments. The u~ual fraction of these material~3 in food and animal feed productæ is between 5 and 30% only.
An improvement o~ the amlno acid compo~ltis:~n can for instance be accompllshed by adding Rynthet1c methionine. However, thi~ composition ~l~o is not sati~actory slnce it only re~ult~3 in an addltive for Ieed products, ~ixture~ o~ one-cell proteln~, cereals and whey powder ~ -are also known. For this purpose one produces the individual com-ponent~3 in advan~e at the desired purity. The produc~on o~ the e individual componentæ, howev*r, i5 highly expen~ive. The principal C03t are the e-,raporation and drying o~ the whey~ the proces2iing of the yeast, which can ~ grown only in compara~ively dilutc substrate solution~3 for instance on ~olas~e~ or sulf ite ~aste liquor, and ~inally the drying o:~ the ~ub~trate and the prior preparaticn of ~he grain~, It is there~ore an object of the invention to provide Ior a process f or making a balanced f ood product includ ing an imal ~eed~
and part~cularly a Ieed product for u~c in bringing up calve~. Thi~
ob~ect includes the purpo~e to obtain the product without unreason~
able co~t and in particular to save in drying co~t in producing the f ~nal product .
According to the invention the whey is aixed with a natural product containing protein and ~tarch whereupon the mixture is sub-~ected to hydroly~i~ o~ the ~t~rch. The thus-~ormed ~ugar is subse-quently converted by means o~ ~icroorganisms lnto one-cell protein and the iermanted sub~trate i~ then sub~ected to concentration by - ~.
evaporation nnd drying.
Thu~, ln the process o~ the invention the ~hey occurring ~8~4~

in the cheese product lon ~erves ~3imultaneously as swell ing agent for in~tallce Ior the cereal~ and as diluent in the hydrolysis thereof. The d ilute whey as it i5 obtailled from the cheese manu-facturer or processing plant is reacted with cereals which are degraded to ~ugar in the whey ltselI. This sugar-containing whley i~ thsn sub~ected to ~erm~ntation with yeast. Aftl3r the ~ermen- :
tat ion it i~ concentrated by evaporat ion and dr ied.
The single Figure ~hows in diagrammatic ~orm an apparatus for use in the lnvention.
The cereals used in the present case may be rye, barley, oat~, mai~e, sorghum, etc. Any natural product, particularly cereals, th~t contaîns a su~i¢ient amount o~ proteinæ and starch are usefulO The cereals may ~ uæed in partly unshelled formO
It is possible to use germinated cereal, in Particular germinated maizeO Preferably~ the cereal may be in form of flour, for in~
~t ance ma ize i lour O
The fer~entation can be carried out with torula yeast ~hich i~ inactive to the lactose, Thus, a protein-containing and :
lactose-containing dry product is obtained. However, it is also possible to u~e a yea~t which i~ active both in respect of the sugar obtained in the hydrolysis of the grain and ln regarcl to the lactose" An example is Sascharomyce~ fragil-is. In this manner all of the sugar can be fermcnted.
By making it unneces~ary to use additional proce~s water, the size of the plant employed in the prOcQss of the -invention can be comparatively ~;mall With reference now to the drawing, the following i~; a descr ipt ion OI the apparatus employed in the process. The refer-ance numeral 1 polnts to a storage vessel f or the ~vhey . The tF o :
port ions OI the conduct ident i~ ied as 2 and 4 are separated by ... ... . . .

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a pump 3 . The two ves~;el~; 5 and 5 ' are of ident ical ~tructure and are equ ipped with st irrer~ 6 and 6 ', a hot water inlet 7 and 7 ' and a hot v~ater outlet 8 and 8 l ~ Th~ connecting oondults are provided ~lth a ,~ack~t or heat coils whach ar e not ~ho~n in the drawing and are o~ convsntional natureO
Both tanks 5 and 5' are connacted by a conduit 9. From the ~econd vessel 57 a passage 10 lead~3 to the Ierementatlon tank 13 via a pump 11 and a conneclting passage lOo The ~ermentat ion tank 13 con~ist~ of a boiler or tank 14 which is prov ided with an air ing dev ice 15 ln the lower port ion of the tank and a Ioam outlet or separator 16 in the top portion of the tank. BaIIle plates 17 and 17' are provided in the side vall~ of the tanlc. The inlet 18 and the outlet 19 serve to adolit arld discharg~ cooling water. Betweerl the ~;torage ve:3sel 1 Ior the whey and the fermentation tank 13l, an additional oonduit 20 is prov ided which, through a pump 21 and a passage 22, is corlllect- ; ~
edl llvith the tank. ~: ;
In the lowel~ port ion o~ the tank a passage 23 i~ prov id-ed for the discharge of the content~;~ Thl~ passage i~i controlled by a valvQ 24. The fermentatlon tank itselI i~; plac:ed on a thrust meter 25 ~vhich, by means OI a cable 26, is comlected w:ith an opti-cal indicator 27 of the weight and i5 connected by another cable 28 witlh the contrs~l valve 240 Ths passage 29 leadæ to a control ves~el 30 and the conduit 31 leads to the multiple member evapora-tor ~ystem 32.
The evaporator as ~hown comprises three stages. This general !3y!3tem OI evaporator is conventional. The vapo~ from the ~ irst stage 321 pa~ses through a conduit 32 and heat~ up the soncentrate which, through the conduit 34, paæs2s into the second , 30 stage 322, The sa~e i~ done llvith the vapor ~hich goes into the .
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, 1 concluit 35. This vnpor heats up the concentra-te which passes through condult 36 into the third stage 323 of the evaporator~
'rhe conduit 37 leads to a condenser wh~ch is not shown in the drawing.
The conduit carrying the concentrate and designated 38 is provided with a pump 39. A connecting conduit 40 leads to the spray dryer 41.
A separate vessel 42 ls provided for receiving liquefied ~at or oil. This vessel is provided with a stirrer 43. An inlet 44 passe~ the substrate from the fermentation tank into this ~ -au~iliary vessel 42. An outlet 45 passes the mixture with the Pat or oil -to the homogenizer 46 and from there through conduits 47 back into the conduits leading to the evaporatar.
48 indicates the packaged material and 49 shows an additional mi~ing device ~or mixing the material with a~y desired additives. 51 would be the discharge conduit ~or the final product.
The operation of the describled apparatus is as follows.
A portion of the whey is wit'hdrawn ~rom the storage vessel 1 via the conduit 2 and is passled by means of the pump 3 and the Eurther conduit 4 into the first processing vessel 5.
The hlgh revolution stirrer 6 does comminute and mix the added ;~
cereal 50 which may be any kind of flour or maize. After heating up the contents of the vessel 5 to a temperature between 50 and 60~C by a heating medium introduced through the duct 7 and dis-charged through duct 8 the first stage of the enzyme action is carried out resulting in a liquefying of the starch present in the cereal.
The liquefied starch then is passed through duct g into the second enzyme ve~sel 5' where the saccharification of the lique~ied starch is e-ffected.
The re~aining salid portions in the hydrolysis produc-t ;

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such as precipitated protein and fibe:rs are removed by means of a sepalator or filter such as ultrafilt:ration. These conventional devices are not illustrated in the drawing. The liquid is then pumped through duct 10 ~y means of a pump 11 and via the conduit 12 into the fermentation tank 13. In this tank the conversion $nto yeast protein is effected upon vigorous aeratlon and by means of special culture yeast such as Candida utilis, Candida tropicalis, or Saccharomyces fragilis.
In order to dilute the substrate resulting from the enzyme actionJ addi-tional whey such as 1/3 to 1/4 o~ the total whey is supplied directly ~rom the storage vessel 1, and passed through duc-ts 20 and 22, and by means of pump 21 into the fermen- -: tation tank 13.
The fermentation is then carried out automatically and :~
is controlled by means of the weighing system consisting of the weight scale 27, connecting cable 26, control valve 24 and cable 28. The collection of the yeast containing substrate is effected via the duct 23 and valve 24 and permits to supply the product in a continuQus operation directly to the multiple member evaporator 2Q 32.
Alternatively, part or all o:E the collected substrate may be passed into the auxiliary vessel 43 via the duct 44 and may be emulsified with oil or lique~ied fat by means o~ a homogenizer 46. The material then can again be passed into the duct leading to the evaporator 32.
The degree of concentration by evaporation can be select-ed at will. IIoweve~, the product obtained must still be suscep- :
tible to conveyance by pump action. The product is for instance passed, by means of a pump 39 and a duct 40, to a spray dryer 41 where it i9 dried whereupon it is placed into bags 48. In the end ; .
it may be mixed with other additives in the mixer 49 and the final ~s~, : 7 ~s~

product may be pas~3ed out through the discharge duct 510 The iollowing exa~nples will further illustI ate the invent ion.

~AMPIE l, , , 1000 liter whey obtained by curdling the chee~e milk by means OI renrlet were mixed ~ith 80 kg o~ wheat ~lour in the Yessel 5, whereupon aIter vigorou~ ~tirring 1110 g CaCl~ (dried) were added O Th is mixture ~hould have a pH o~ 6 . l and, iI neces-sary, is ad,~usted to this pH by m~ans of HCl or NH4aH. 500 g alpha-amylase (HT-1000 IYlil~s Laboratory~ were then added and the mi~cturs wa~3 heat~d to 6Q& ~hile st1rring. The reaction ~as kept under cont~ol by mean~ of KJ/J2.
In ca~e o:e a eontil~uous operation of the subse~uent ferm~ntation the cs~ntents OI the vess~1 5 are passed through the - -.
duct 9 into the Ye~sel 5 t alld pa~teur ized in the latter vessel at 80C ~ilereupon they were cooled down to 38&.
The ferm~3n~ation in the tamk 13 wa~ effected with an adapted species of Candida trop~calis at 38& and at a pH OI 4 whis~h was ~aintained constault by mearl~ OI a dilute ar~mo~ia ~olu- ~ ;
tion (25% ~H4C~)o me aer~tion rate ~aE; alse kept c~onstant at ~ ~
005 to 1.0 vYm. ~ :
In case of a ~atchwi~e operation o~ the ferm~ntation ~
pr~e~s the operation Pra~ I lnished in about 6 to 8 hoursO In ~ -cas~s of a continuous ferm~ntation th~ ermentation solution was co}ltinuou~ly pa~sed inlto ~he auxiliary ve~sQl 42, It ~ po~sible ~or thi~ purpo~e to provide for two ve~els of thi~ kind.
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After a certain level i8 reached in the container 42 the pH i~ adjusted by mean~ c~f Na~ to 7.5 while ~tirring. The cell ~uspension wa3 then mixed with vegetable oil i~ an amount OI
5 .5 kg and mol~en ani~al fak in the sa~e amount and I inally :: , ~.
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emuls~f ied in the homogeni~Aer 46. The stability o~ the emul~3ion wa~ increa~ed by add ~ ng 1000 g o~ lec ith in.
The re~ult ing emul~lon was pa~sed to tha evapora'cor 32 and concentrated to one half of the original volums. Ths drying was effected in a ~;pray dryer a~ shown, but could al~;o be done in a roller dryer.
Instead OI the ~heat flour used in this e~a~ple, rye, .
barley, oats7 maize or sorghum could also b~ u~ed.
The compositiorl of the I inal product obtained i~ as f~llow~:

Lacto8e 44 kg 38.1 %
Protein 27.5 kg 2308 % 24.3 *
Carbohydrate~ ~yeast) 9.3 kg 801 '%
~alt~ 11.1 kg 9.6 % 8.75*
Fat 12.8 kg 11.1 % 9 Fibrouæ material 1.5 kg 103 %
~ater 9 . 2 kg~ 8 ,, 0 %
~15.4 l~g 100 % ~:

~0 *value~3 obtained by analysis EX~ E 2 1250 1 o:~ chee~3e whey with a contents OI about 4.2% o~
la~to~;e and 0, 7% o~ whey protein were passed into ths vessel 6 which had a capacity of 2000 lo The contents were heated to a tempsratur~ of 50 to 60&. ~0 kg o~ fractured unshelled maize and 50 kg o~ wheat ~lour with a protain content~ of 12% wera then : ;
mixad into the whey by ~tirring. A:Eter adding 1000 to 1200 g OI

calc~um chloride 0.10 to 0.15% (according to ~tarch content~) of alpha-arn3~1a~e (HT-1000, l~[iles Laboratoris~) were th~n added and the temperature v/as increased to 7$ to ~o&. A~ter 1 to 2 hours _ g _ :

, the grain con~ponent ~as practically all dis~olved excepting only the grain ~ibers and a ~mall portion of ~oteinO
The p~ was then adjusted by HCl to 31.8. The tem~rature was not lowered to 50 to 55&. There were then added 0.15%
(accordlng to starch oontent ~ Amrlogluco~ida~e ~L-100 Diazym, ~liles Laboratories) and the mixture wa~ lqell homogenized and left standing for 24 hours. I t was thereaftsr heated to a tampsrature OI 80 to 90& and ~vas separated from the ~ ibrous components and precipitated whey-prot0ins by centrifu~ing.
Dcpending on the f iber components and the degree o~
drying, the result ing coneentrate amounted to betwaen 17 and 25 kg ~d had a protein contents OI 6S) to 65%. The separa,ted liquid :
from the centrifuging step contained the saccharified starch from the maize and the wheat flour and the lactose from the whey. It was fermented thcn wilth Candiela utilis or ~accharomyce~ fragllis ::
as in Example lo ,.

EXA~PI.E 3 The proce~s of E~ample 2 was repeated but different eereals than the ~wheat flour of Exampl~3 2 were used as appears ir~ :~
the.table b~ which also shows the slightly varying composition OI the f inal product TABLE 2 :
yeast carbohy- f ibrous -lactoseproteilldrates salts fat materials ~vater rye 3800 23.8 8.6 9.6 1007 1.3 8.0 %
barley37.7 23.6 8.5 gO4 10.6 2.2 800 % .
oat~ 37.6 23.9 8~5 903 1403 1.2 ~.0 % ; ~
maize37.9 2206 8.S 9.1 1204 1.4 8.0 S : :
sorghum 38,0 23.0 8.6 905 11.8 1.1 800 %
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In order to obtain a milk ~3uited ~or use in cattle breeding for bringlng up calve~, 75 kg o~ any o~ the products OI
l'able 2 ~ere mlxed with 25 kg of sklm milk~ The f inal milk com-position thersIore ~a~ one quarter skim milk and three quarter~
proclu¢t according to Table 2. The mi~ture contained 28% protsin o~ which one half each con~isted OI milk protein and other proteins.
Tests carried out for many year~ with calves have sho~n that for bringing up calve~ 30 to 50% of the milk proteins can be replaced by y~a~3t proteinsO The products of the~ pre ent invention, in addition to the proteins pre$ent ln the whey and depending on the type o~ grain employed contain protsins of dry yea~t and native proteins from the grain. Thus a well bal~nced a~lno acid spectrum is obtained.
Thl~ compo~ition of the proteins assures an adequate supply of the growing cal~ with the e~sential amino acids and vita-rnins .
The protein fractions can aLso be baked into a hard bak-ery product by addition OI yeast. Th~3 soluble protein fraction can be proc¢ssed for the ~ood indu~try by u~iing foaDIing agentsO
2û ~Yithout further analysis, the foregoing will so fully reveal the gist of the pre~Qnt invention that othQrs can, by ' ."
applying current knowledge, readily adapt it for various applica-kions without omittin~ features that, from the stalldpoint of prior art, fairly con~titute essential characteristics of the generic or spacific a~pects o~ thi3 invention.
What i~ claimed as new and desired to be protacted by : ~-Letter~ Patent i~ ~t forth in the appendcd claim~.

Claims (18)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A process for making animal feed and other food products from whey comprising the successive steps of (a) mixing the whey with a natural starch and protein-containing product;
(b) hydrolyzing the starch in said mixture so as to convert it to a sugar;
(c) converting the sugar into yeast protein by fermen-tation through the action of microorganisms so as to obtain a fermented yeast-protein-containing material, and (d) concentrating said protein material by evaporation and finally drying it.

2. The process of claim 1 wherein cereals are used as the said natural products.

3. The process of claim 2 wherein the cereals are at least partially in unshelled form.

4. The process of claim 2 wherein germinated cereals are used.

5. The process of claim 2 where in the cereals are used in the form of flour.

6. The process of claim 1 where in the said hydrolysis is elected at an elevated temperature.

7. The process of claim 1 wherein part of the whey is directly passed to the fermentation step so as to dilute the hydro-lysis product subjected to the fermentation and the resulting fer-mented substrate.

8. The process of claim 1 wherein the mixture of whey and natural product is subjected to a two-stage enzyme action prior to said fermentation, in the first stage the starch of the cereal being liquefied and in the second stage the liquefied starch being saccharified.

9. The process of claim 1 wherein oil or liquid fat is added to part or all of the fermented protein material prior to the concentration step and the mixture is subjected to emulsifi-cation and homogenizing.

10. The process of claim 1 wherein the fermentation is effected by means of active yeast cultures.

11. The process of claim 10 wherein the yeast culture is selected to be active only in respect of the glucose and inac-tive in respect of the lactose present in the hydrolysis product.

12. The process of claim 1 wherein part of the protein present in the hydrolysis product is precipitated by heat.

13. The process of claim 1 wherein part of the protein present in the hydrolysis product is precipitated by heat.

14. The process of claim 13 wherein the precipitated protein solids and fibrous materials present in the hydrolysis product are separated subsequent to the hydrolysis and prior to fermentation.

15. The process of claim 14 wherein the separation is effected by ultrafiltration.

16. The process of claim 1 wherein a hard bakery product is formed of the protein fractions upon addition of yeast.

17. The process of claim 1 wherein the soluble protein fraction obtained in the final product is used in food products upon addition of a foaming agent.

18. An apparatus for converting whey into a useful food or animal feed product in a process as defined in claim 1, the said apparatus comprising a storage vessel for the whey;
a first vessel for mixing the whey with a cereal and liquefying the starch contained therein;
a second vessel for saccharifying the liquefied starch;
connecting means between said storage vessel and said first vessel and between said first vessel and said second vessel;
means for supplying hot water to said first and second vessel;
a fermentation tank;
a connection between said second vessel and said fermentation tank;
a connection between said whey storage vessel and said fermentation tank;
an evaporator;
a connection between said fermentation tank and said evaporator;
drying means connected to said evaporator;
at least one auxiliary tank for holding oil or liquid fat;

an inlet to said auxiliary tank communicating with said fermentation tank;
a homogenizer associated with said auxiliary tank for receiving the mixture of oil or fat and fermented substrate;
and an outlet from said auxiliary tank communicating with said evaporator.