FERMENTATIVE PROCEDURE FOR FEED PRESERVATION AND AN ADDITIVE FOR PERFORMING THE PRESERVATION

Abstract: A fermentative procedure for preserving protein feed with the aid of lactic acid producing bacteria in the presence of carbohydrates so that fermentation starts and takes place fast and more efficiently and more reliably than before; according to the invention to protein containing feed material are added gluconodelta-lactone and carbohydrate-cleaving enzyme.

Description: Fermentative procedure for feed preservation and an additive for performing the preservation . The presen t inven tion concerns a f rmen tative procedure f or preserving pro tein f eed with the aid of l actic acid produc ing bacteria . The inven tion f urther concerns an additive for preserving pro t feed wi th the aid of l actic ac id producing bacteria . At present, protein feed, such as fish, fish offals, slaughter offals, etc., sire mainly preserved by acidifying, refrigeratio drying and fermenting. Refrigeration, and deep freezing in particular, causes high apparatus and energy costs. Moreover, refrigeration fails to prevent spoiling of the feed e.g. when the feed is used after has been thawed. Drying involves likewise high energy costs. In addition, the value in use of the feed is impaired owing to changes taking place in the feed raw material during drying. Fermentative preservation methods are based on the use of lacti acid bacteria in such manner that they pr duce lactic acid from carbohydrate contained in the feed raw material or added theret The raw material used in connection with fermentation, local conditions and temperature and fermentation arrangements have given rise to problems in the form of improper fermentation and of product spoiling. Improper fermentation is due to lactic aci fermentation failing to come under way correctly, or to imprope organisms gaining ascendance and thus causing spoiling of the r material . The object of the present invention is to eliminate the above- mentioned drawbacks occurring in connection with fermentative preservation methods, and to provide a novel fermentative proce dure for preserving protein feed in such a way that feed preser vation will be accomplished more reliably than before, with le instances of improper fermentation than before and with best results possible, that is, without spoiling of the eed. It is furthermore an object of the invention to provide a novel fermentative procedure for preserving protein feed so that fei— mentation starts and takes place faster and more efficiently th before. Moreover, it is an object of the invention to provide an additi which is intended to be added to protein feed raw material so that, fermentation can be accomplished more advantageously and more reliably than before, in accordance with the foregoing- Regarding the features charac erizing the invention, reference made tα the Claims. The invention concerns a procedure for fermenting mainly feed r material of animal origin, i.e., of raw material containing mainly protein of animal origin. Most of the procedures previou ly presented relate to lactic acid fermentation of raw material of plant origin. Fermentation proceeds in different manner in a product of animal origin from that in a product of plant origin The invention is based on the use, in connection with lactic ac fermentation, of glucono—delta—lac one and of carbohydrate—clea ing and oxygen—eliminating enzymes. Ey action of glucono—del a- lactone, the pH of the protein feed raw material can be rapidly and efficiently brought down far enough so that the growth of improper organisms is inhibited, that is, improper organisms cannot gain ascendance in the raw material mix, and improper fermentations as well as product spoiling a.re prevented. By action of carbohydrate—cleaving enzymes, the cleaving of carbohydrates, e.g. of starch, to mono— and disaccharides is enhanced, and the growth of lactic acid bacteria using them for their carbon source is strengthened. The additive of the invention for preserving protein feed con tains said glucono-delta-lactone and said carbohydrate-cleavi enzymes. When the procedure and/or the product of the invention is use it is achieved that preservation of protein— ontaining feed r material will be reliably and repeatably successful, without improper fermentation and spoiling of the product in circumst ces of actual practice. The procedure is also danger—free to person applying it. The procedure of the invention and the use of the product of invention is easy and simple, and they imply no extra investm on top of the equipment used in conventional fermentative pre serving procedures. Furthermore, the operating cost of the pr dure is favourable, for instance compared with deep—freezing drying. The product obtained by the procedure keeps well and i not subject to spoiling e.g. in connection with its use. In the procedure of the invention conventional bacteria used i connection with lactic acid fermentation may be used, for in¬ stance Lactabacil l us acidaphil us r Lactabacil lus bulgaricus, Lactobacil l us casei f Lactαbacil l us hel veticus f Lactabacil l us lactis, Lactαbacil l us plantarum, Lactαbacil l us curvatus, Lacto bacil l us sake, Pediocαccuε acidil acti f Pediαcoccus cerevisiae, Fediαcαccus pentαpaceus , Streptococcus faecium and Strepto¬ coccus lactis . Partcularly advantageous are homofermeπtative non—proteolytic lactic acid bacteria, that is, those which produce no gas in connection with fermentation. The procedure and product of the invention are applicable in preserving feed raw materials containing protein, such as fish fish offals, slaughter offals, meat—bone meal and equivalent f raw materials. The endogenous enzymatic activity of the feed raw material may detrimental in view of fermentation. It is therefore a van taqeo to pasteurize raw materials which have a high content of own enzymes (e.g. slaughter offals), that is, to heat them about 5 minutes at a temperature between 6υ and 90 C, C, whereby the enzym are inactivated. Another conceivable way to inactivate the raw material's own enzymes is to use special inhibitors, for instance the product named "Pepstatiπ" marketed by the company Sigma Che . , which is hexapeptide preparation. Protease inhibitors are mostly compoun with peptide structure. Such inhibitor is typically used in a quantity on the order of 1 g per kg feed raw material , for instance 0.3 to ' 3 mg per kg feed raw material. The quantity of glucono—delta—lactone added is appropriately su that the pH of the feed raw material goes down below 5.5 within few hours, e.g. 1—4 hrs, such as less than 2 hrs, advantageou l about i hr. Desired effect on the pH value is usually achieved with a lactone addition of 0.1 to 2.7.. advantageously 0.5%, re¬ ferred to the feed raw material quantity (the feed raw material consisting e.g. of slaughter offals with dry matter e.g. 10 to 70%, appropriately 25 to 35%, the glucono-delta—lactone quanti¬ ties calculated on the total quantity including water) . The additives or enzyme mixes that are used contain advantageou ly a ylase and/or glucose oxidase. In addition, the enzymes may contain e.g. alpha—amylase, beta—amylase, glucoa ylase, beta- glucanase, cellulase, hemicellulase, pectinase, lactoperoxidase, lactase, lysozy e, alpha—galactαsidase, phytase, etc. The purpo with the enzymes is to cleave carbohydrates, that is starch, to mono— and disaccharides so that lactic acid bacteria may use th for their carbon source. In addition, if desired, one may use a oxygen—eliminating enzyme in order to achieve anaerobic fermeπt tioπ and to speed up the lactic acid fermentation. In order to improve the digestibility of plant raw materials, one may use i the procedure, and the additive of the invention may in additio contain, other enzymes, e.g. those cleaving cellular tissues o plants, such s≡ The glucono—delta—lac tone, the enzyme mix and the lactic acid bacteria, and possibly carbohydrates, may be added to the feed raw material in combination or separately, taking practical circumstances and requirements into account. Furthermore, the additive of the invention tar preserving protein feed may com¬ prise one mix containing the above—mentioned components and wh is meant to be added to the feed raw material at one time. I he additive may alternatively comprise several separate mixes, ea containing one or several of the above—mentioned components, a said mixes being intended to be added to the feed raw material combination or separately. The amount of lactic acid bacteria in the additive is for in¬ stance such that the additive, when added to the feed raw mate al, produces an initial bacterial content e.g. of about lo 3 to 10 Θ per g, suitably 10° to 10* per g. At the end of fermen ati the lactic acid bactery count is e.g. lυ"- to 10 io , suitably 10 to 10 * *. The ultimate pH of the fermented feed is 3.5 to 4.5, suitably to 4.2. The fermenting temperature is below 50°C, suitably 15 to 40°C, for instance 20 C *C. The carbohydrate source used in the procedure and containing t above— entioned additives is e.g. barley, oats, wheat, molasse or another equivalent carbohydrate source known in feed indust The carbohydrate is advantageously gelatinized, e.g. treated in an extruder. The invention is described in the following in detail with the aid of embodiment examples, yet without restricting the inventi to the examples presented. Example 1 A raw material mix containing fresh or frozen fish or fish offa 650 kg, soybean meal (extruded) 90 kg, wheat flour (raw and/or roasted) 250 kg, is heated (e.g. with hot water) to 18—30 0 C. Th fish is ground to pulp, transferred into a mixer, and into this are dispensed preservative mixtures 1 and 2 (mixed in 3 1 of water), and carefully mixed. The compounded mass is transferred in a covered vat, degree of filling less than 85%. The vats 'are hermetically sealed, stored at 20—25*='C for at least 3 days, un pH is less than 4.3. The pH of the mass goes down immediately upon adding the preservative mixture. Preservation of the prod is considered successfully accomplished when pH reaches the val 4.2 within 3—4 days. As soon as pH is below 4.3, the product m equally be stored in colder environment, though not so cold th the product would freeze. In the case of silo storage the silo communicates with the outdoor atmosphere by so— alled breather tubes. Preservative mixture 1 contained: glucono—delta—lactone 6.45 k barley flour 3.53 kg, glucose oxidase (12 500 u/ml ) , io g (cat.neg.), alpha—amylase 3.8 g, glucoamylase 3.8 g, and cεllu lase 3.S g. Preservative mixture 2 contained: product sold urid the trademark name Lactostart 03 (Chr. Hansen) 50 g, and produ sold under the trademark name Pediostart 40 (Chr. Hansen) 38 g. Example 2 70—80% of preserved mass as obtained in Example 1, 20—25% fish meal, 2% vitamin mixture, 3-8% alginate, 2-4% fish oil, υ-2% wheat bran and O—0.1% preservative are mixed together and pell ed. The pellets are packed in a plastic box, in which they may stored for 1—3 days, protected from sun and rain. Example 3 900 kg slaughter offals (heated at 60°C for 5 miπ.) (pork, ne poultry), 90 kg feed wheat (roasted or raw) and lO kg preserv tive mixture containing alpha-a ylase 10 g/ton, glucoamylase 1 g/ton, glucoπo-delta-lactone 5.0 kg/ton and barley flour 4.98 kg/ton were mixed together, and hereto was added preservative mixture containing Lactαstart 03 10-160 g/ton and Pediostart 10-50 g/ton. After mixing, the mass is pumped into a silo. The silo is kept at 25-35°C for 3 days. Hereby the pH of the mass goes down to 4.2. If required, the slaughter offals may be pasteurized according need and conditions, as has been set forth in the foregoing. Storage takes place in hermetically closed silos, the only com munication with external air a breather tube. Example 4 raw material mix containing Baltic herring 850 g Extruded wheat flour ISO g Lactostart 03 (Hanson) 50 mg Pediostart 40 50 mg W s heated to 20°C and thereto was admixed preservative mixtur 1% of the raw material mass. The preservative mixture containe Mould alpha—amylase 2.0. g Glucoamylase 200 2.0 g Beta-a ylase (BBA 15 ) 10.O g Glucose oxidase (10000 U/ml ) 1.0 g Cellulase 1.0 g Glucono-delta-lactoπe 500.0 g Extruded soybean meal 484.0 g The pH of the mass thus obtained was 4.3, 4 days after ferment tioπ. B Example 5 The raw material mix containing preservative was carefully mixe and transferred into a fermenting vessel. The raw material mix contained: " Slaughter offals, ground 840 g Extruded wheat 155 g Mould alpha—amylase 30 mg Beta—amylase 30 mg Cellulase 40 mg Glucose oxidase 100 mg G1ucoπo—de1ta—1actone 4.8 g Lactic acid bacteria mix 100 mg Fermenting was allowed to proceed for 2ϋ days, and the pH of th product developed during fermentationm as follows: Storage time. pH Acid number, days ml 0.1 N NaOH/lOg 1 4.7 12.3 2 4.4 22.6 3 4.3 25.4 10 4.0 35.0 20 4.0 36.6 Example 6 Example 5 was repeated, using a mixture of raw material and preservative, containing: Ground fish/fish offals 800 g Extruded wheat 100 g Extruded soy 100 g Glucono—delta—lactone 6.4 g Bacterial alpha—amylase 12 g Glucoamyl se 12 mg Cellulase 15 mg Glucose oxidase 14 mg Lactic acid bactery mix 100 mg pH and acid number of the product developed in accordance with Example 1. Example 7 Example 6 was repeated, using ground slaughter offals instead ground fish. The results were consistent with those in Example Example 8 A raw material and preservative mix containing: Ground slaughter offals 128 kg Extruded wheat/barley mi ture 20 kg Whey concentrate 30 kg Glucono-delta-lactone 7.5 kg Glucose oxidase 1.5 g Alpha-amylase 1.5 g Beta— mylase 1.2 g Beta—glucanase 1.5 g Hemicellulase 1.0 g Lactic acid bacteria mix 10 g is fermented as in Example 1. Instead of whey concentrate and extruded cereal may be used glucose, saccharose or lactose, in solution or crystalline form. Example 9 In this trial a raw material and preservative mixture was fer— mented which also contained mould inhibitor. The mixture had th following composition: Ground fish 900 g Extruded cereal 100 g Glucono-delta—lactone 6.5 g Alpha—amylase 10 mg Glucoamylase 10 mg Potassium sorbate 1000 mg Lactic acid bacteria mi;; lυO mg pH and acid number of the product developed as follows during fermentation: Storage time, pH Acid ni days ml 0.1 0 6.3 1.9 1 5.6 6.9 4.6 18.8 3 4.5 22.3 14 4.2 40.3 28 4.2 42.2 The results reveal that use of mould inhibitor is feasible in connection with the fermentative procedure of the invention. Example 10 Example 9 was repeated, using instead of sorbate, lipase and an lysozymε 100 mg per kg raw material. pH and acid number of the product developed as follows during fermentation: Storage time, pH Acid number, days ml O.l N NaOH/lOg 0 6.1 4.0 1 4.4 24.0 12 4.2 43.5 Example 11 A raw material and preservative mixture was fermented as in Example 9. The mixture contained: Ground fish 840 g Preroasted cereal 150 g Alpha— mylase 30 mg Beta—amylase 30 mg Cellulase 40 mg Hemicellulase 20 mg Glucose oxidase 10 mg Glucono—delta—lactone 5 mg pH and acid number of the product thus obtained developed as follows during the fermentation and preservation period: Preservation time, pH Acid number, months ml 0.1 N NaOH/lOg O 5.4 6.5 1 4.3 33.4 2.5 4.0 33.1 3.5 3.9 36.5 4.5 4.0 36.0 5.5 4.2 36.4 6.5 4.1 37.3 The embodiment examples are merely meant to illustrate the inv tion, and embodiments of the invention may vary within the sco of the claims following below.

Claims: CLAIMS 1. A fermentative procedure for preserving protein feed with t aid of lactic acid producing bacteria in the presence of carbo— 5 hydrates, characterized in that to protein—containing feed raw material is added glucono—delta—lactone and carbohydrate— leavi enzyme. 2. Procedure according to claim 1, characterized in that glu — 0 ono—delta—lactone is added so that the pH of the feed raw mater al goes down below 5.5, advan ageously within 2 hours. 3. Procedure according to claim 1, characterized in that gluc¬ ono—del a—lactone is added 0.1 to 2.0% by weight of the feed ra 5 material quantity. 4. Procedure according to any one of claims 1—3, characterized in that to the feed raw material are added amylase and glucose oxidase. Q 5. Procedure according to any one of claims 1—4, characterized in that to the- feed raw material is added an oxygen—eliminating enzyme. 5 6. Procedure according to any one of claims 1—5, characterized in that to the feed raw material is added alpha— mylase, beta— amylase, glucoamylase, beta-glucanase, cellulase, hemicel lulase pεctinase, glucose oxidase, la operoxidase and/or phytase. 0 7. Procedure according to any' one of claims 1—6, characterized in that to the feed raw material are added homofermentative lactic acid bacteria. 8. Procedure according to any one of claims 1-7, characterized " 5- in that the feed raw material is heated for 5—10 minutes at 60— 0*=*C in order to inactivate the endogenous enzyme activity o the raw material . 9. Procedure according to aby one of claims 1-B, characteriz in that the endogenous enzyme activity of the feed raw matσri is inactivate with an enzyme inhibitor. 10. An additive for preserving protein feed with the aid of lactic acid producing bacteria, intended to be added to the f raw material in connection with starting fermentation, charac ized in that the additive contains glucono-delta—lactone and carbohydrate-cleaving enzyme. 11. Additive according to claim 8, characterized in that the additive contains amylase and glucose oxidase and possibly al ha-a ylase, be a-amylaβe, glucαa ylase, beta-glucanase, ce lase, hemicellulase, pectiπase, glucose oxidase, lactoperoxid catalase, lactase, protease, lysozyme, alpha-galβctosidase an phytase- 12. Additive according to claim θ or 9, characterized in tha the additive contains homαfer entative lactic acid bacteria.

Inventors: AALTONEN PIRKKO, LAITINEN MATTI JUHANI, AALTONEN, PIRKKO, LAITINEN, MATTI, JUHANI
Applicants: SUOMEN SOKERI OY
Application year: 1987
Main classification: A23K3
IPC codes: A23K1, A23K3