GB2416661A

GB2416661A - Processes for improving binding capability and biological digestibility

Info

Publication number: GB2416661A
Application number: GB0519982A
Authority: GB
Inventors: Anders Aksnes
Original assignee: NORWEGIAN INST OF FISHERIES AN
Current assignee: NORWEGIAN INST OF FISHERIES AN
Priority date: 2002-01-07
Filing date: 2003-01-07
Publication date: 2006-02-08
Anticipated expiration: 2023-01-07
Also published as: GB0519982D0; GB2416661B

Abstract

The present invention describes processes for obtaining a fish product with improved binding capabilities. Gelatine is liberated from collagen in connective tissues, skin and bones that is naturally present in the fish raw material as the product is produced from. Further, the present application describes processes for improving the digestibility of bone bounded minerals in feeds. Bone tissues are treated with acid or alkali wherein the bone tissue is solubilised. Preferably, the acid is hydrochloric acid at a concentration of 0.5 to 3M.

Description

Processes for improving binding capability and biological digestability.

FIELD OF THE INVENTION

The present invention relates to a process for improving the binding capability of a fish material. The invention also relates to a process for improving the biological digestibility of a feed product made of a raw material. In a further aspect the invention also relates to process for increasing both the binding capability and the biological digestibility of a product. and to a product manufactured in accordance with this 0 process.

N tore specifically. the present invention relates to a line of action to processing of fish or pale of fish. for liberation of gelatine. Id/or for improvement of The biological digestibility /.t these and thus for reduction of effluents and improvement of the environment.

BAClGR(LiLID FOR THE INVENTION In the production of feed for fish and animals it is important that the various ingredients 3u are hold together in one larger feed particle. Binding agents are used for this purpose, and these are often carbohydrate containing compounds. These binding agents may be indigestible for the animal or fish that are fed.

Industrial feeding is dependent on good physical characteristics of the feed particles.

o5 One needs feed particles that are kept together and not broken at transport storage.

handling and feeding. In some type of feeds (for instance feed for eels! it is important that the feed are like a dough and that the eel can eat small bits of the feed particles in a Ivan, that keep the rest of the feed particle as an unbroken particle. This will depend on the characteristics of the feed ingredients Ed the binder that are used. Good binding to capability; is also important in production of fish products as for instance fish balls and calves.

An object of the present invention is to increase the binding properties of a product without the addition of a binding agent. The binding properties are improved by activating inherent binding capabilities already inherent in the raw material. Such a material with increased binding properties may open new possibilities for the use of new fish species for manufacturing of food product for human consumption and also for the production of improved feed products.

The processes and products according to the present invention reduce or eliminate the requirements for the supplementing of binding agents.

Fish meal is an important ingredient in feed for fish and animals. and fish reed may contain 0-,0 0 of the total dry matter as fish meal. Fish meal is produced from whole fish and parts of fish that contain collagen rich protein; bone. song tendons and corrective tissues.

Without being bound to a specific theoretical 1.nechanisnl it is believed that the inherent binding capability of the raw material is activated or induced by a conversion of collagen to a gelatinous component. It is thus preferred that the raw product contains to collagen.

Gelatme is a mixture of proteins and may be liberated from collagen from these tissues by chemical Or thermal methods.

The prior art discloses methods for isolation and extracting of gelatine from a sample.

Most often. gelatine is liberated by heating in hot water. The gelatins that can be liberated by known methods has a characteristic composition of amino acids rued special properties by making a jelly at low concentrations in water.

so A Luther object of the present invention relates to a process for malting minerals that are present in bones as crystals snore soluble and thus digestible for the consumer.

Raw fish bones contains about:0% dry matter. and thereof about 25% collagen, 5-10% lipids and about 0% ash. [vIore than half of the ash is calcium and phosphorus and are used to build the bone structure. These minerals are present in the bones as crystals of hydroxyapatite (Cas(PO) 3(OH)) and calcium carbonate (CaC03). These are stable chemical compounds that: e difficult to liberate in the intestinal tract of animals and fish. The digestibility of minerals from bone is therefore low (0-0% digestibility of phosphorus in salmon) and a significant part of these minerals are effluents to the environment as indigestible nutrients. Increased level of phosphorus (as phosphate) in lo the environment causes good conditions for growth of microorganisms. The overnrnental rules are therefore strict for the maximum allowable content of phosphorus in the teed. If at the same tine, the digestibility of the phosphorus is low (that are the situation in feed for fish). the biological availability may be too low. This may result in deceases due to shortage, deformation in the skeleton or fish deftly 1' It is known that water soluble minerals have good digestibility in fish feed for instance !00% for phosphorus in sahnon), but governmental regulations for total level of certain minerals limit the possibility to add minerals with good digestibility. Especially this is the case for phosphonts. It is therefore a demand and need for minerals that are naturally so present in the raw materials, are available in a chemical form that are easily digested.

DESCRIPTION OF THE INVENTION

Connective tissues, skin and bone fron1 fish raw materials. contain a potential for liberation of gelatine. This will have binding properties that will improve the physical characteristics in processing of feed and fish products by keeping the particles in the product together. Further. bone contains indigestible minerals. These may be dissolved at processing and thus make them digestible for the organism to be fed. In processing of fish bones. liberated gelatine may be combined with dissolution of bone-bounded minerals and thus make the minerals soluble in water with improved digestibility. In this way, the same fish bones are used tor both Improvement of binding capacity by increased Palatine content and increased digestibility of bone-bounded minerals. mainly calcium and phosphorus.

The invention may also be used for other applications where binding property of the product to be processed needs binding capacity. This may be the case when fish raw materials are used directly in feed processing or in products for human consumption where the fish raw materials are mixed with other ingredients as for the production of for instance fish balls or fish cakes.

o Solubilization of gelatins *om collagen protein in skill and bone is in the present ins ention utilised in the same pr oduction and are therefore present in the same products that are produced.

As preferred raw material for application of the intention may l e fish, by-products from the fish industry or intermediate products in fish processings. By-products from fish processin, nonnally contain high levels of sicin and bones after filleting or deskinning As an example for ir.terrnediate products that may be used is bone particles from fish Neal processing that are collected by sieving before milling of the fish meal. In this case. gelatine has to be liberated by chemical or thermal processing. Liberated gelatine so with binding properties is then returned to the fish meal and dried and milled as usually in flee production. This produces a fish meal with improved binding property, and the feed pellets are kept together by the gelatine that is present. Liberation of gelatine from fish bone play be performed by heating in water, high pressure cooking or by repeated or continuous extraction by hot processing liquids (for instance stick water).

By-products from the fish industry are also used as raw material for fish meal processing. For this kind of raw material, gelatine witl1 binding property may be liberated kv chemical or thennal methods before it is used as raw material in fish meal processing. In this way a fish meal with gelatine is obtained and thus a fish meal with improved physical properties for feed production.

The liberation of gelatine from fish bone results in a matrix of minerals where protein and other carbon-containing compounds are removed. I hese minerals are however still present as hydroxyapatite and calcium carbonate and have low digestibility in some biological organisms (e.g. fish). According to the present invention these minerals are made soluble and thus dissolved in the aqueous phase. This can be conducted by chemical treatment: acid. alkaline or high ion-concentration (i.e. salts). The minerals will be present as dissolved ions and thus have a high digestibility. When the dissolved minerals are returned to the fish raw material or intermediate products in the fish meal processing, a higher digestibility of these minerals will be obtained.

By sieving of unmilled fish meal, bone particles are removed and thus most of the minerals that are present in stable chemical compounds and thus have low digestibility.

By dissolving the mineral complexes and return them. a significant increase in digestibility ofthese minerals me obtained. The ultimate goal is a feed ingredient from fish raw material where the fraction of indigestible minerals are reduced and the fraction of digestible minerals are significantly increased.

EXPERIMENTAL SECTION

an Example I

Preparation of oelatine-sample from fishbone Bone from salmon back was rinsed for muscle tissue. added 3 parts of riveter and heated for 10 hours at 100 C. The water phase was separated from not solubilized bone residue by a 1 mm sieve and then filtered trough paper to remove small amounts of sludge. As shown in table 1, the phase mainly consists of solubilized protein (gelatine) that is liberated fiom the salmon bones. The unsolubilized residues looked like perforated spinal cords and that were crispy and east to break between the fingers. As also shown so in table 1, this residue was mainly ash.

Table 1.

Chemical composition of fish bone and fractions after heating.

All values are in To of the samples.

Dry matter | Protein | Lipid | Ash | Calcium Phosphorus Fish bone52 1 o0 5 1 96 1 10 5 Water phase11 1 10! <1- Residues36 | 3 _ I _ Test for bin Cling property in fish meal lo fish meal from Norway Noms added to the above prepared water phase in an amount equivalent to 2.5% of dry matter. Allis is about equal to the amount of dry matter that was liberated from the bones adjusted to the whole fish weight. Water was added to a total water content of 5 ,o. Tile mixture was blended in a m.o.-ar. A control group novas treated similarly except that \vater instead of gelatins extract was added to the fish meal.

The fish meal lead the following chemical composition before addition of water or solubilised gelatine Tom fish bone: Water 9.% So Protein 69.5% Lipid 1 1.% Ash 9 8% Pellets ere made by pressings I gram samples of tle mixtures in a steel cylinder with a piston. Two series of pellets were produced using two different piston pressures. 57 kiloponds and l lS Iciloponds. The compressed pellets revere about 1.5mm in diameter and 7 non height. The pellets were dried at JOC over night.

The quality of the pellets Divas tested in a Pharma Test model PTB3 1 I P. This works by putting a continuously increased pressure on the pellets and the pressure where the pellets are broken into pieces is registered. The equipment has a lower limit of 1 lcilopond and a n upper limit of 30 kiloponds. Table 2 a shows the power needed to break the pellets fiom the control group and the group added solubilized gelatine in pellets produced by using a pressure hl the cylinder of 115 kiloponds. Each group was tested with the cylindrical pellets in upright and Iying position. Similar values are given in Table 2b for pellets produced by 57 kiloponds.

Table 2.

Number of fish meal pellets tested, and the power needed to break the pellets 2a. Fish meal pellets produced at I 15 Liloponds | Pellets Iying Pellets upright

I

Number Kiloponds Standard Number Kiloponds Standard Added tested for breach deviation tested for breach deviation Water (control) 16.0 1.3 < 1 | Solubilised,elatin 5 1 >30 1.S i 0.2 fib. Fish meal pellets produced at 57 kiloponds | Pellets Iying Number I Kiloponds Standard Added tested | for breach deviation Water (control) 10! 13.4 0.9 Solubilised gelatine 5! > 30 o x As clearly shown in Table the pellets that contain solubilized gelatins needs higher pressure before the pellets are broken and thus that solubilized gelatine increase the binding capacity. An other significant difference between the groups is that the pellets from control group was broken into many small pieces while pellets produced from fish s meal added solubilized gelatine were broken into in a much fewer greater pieces.

Example {I

Test for binding capacity in a feed mixture. lo

similm experiment as described in example I was carried out with a feed mixture instead of fish meal. All additions Ed treatments were otherwise as described in example L The feed mixture had the following content before addition of rater or solubilised Relative from;sh bones: Fish meal 65% Cellulose 1 5% Oil 10% Corn starch 7 /o to Vitamins and Minerals ?.5% Lecithin 0.5% The chemical composition of the feed mixture was: dry matter: 92.3%; protein 46.6%.

carbohydrate 0.4% and lipid 15.7%.

The resmelts from the test to measure the power needed to break the pellets produced from the feed mixture ale given in Table 3. a)

Table 3.

Number of pellets tested, and the power needed to break the pellets.

-

3a. Pellets trom feed mi:;ture produced at I lS kiloponds.

Example III

l 5 Solubilization of minerals from fish bone Minerals in bone material may be separated from collagenous bone proteins by acid or alkaline treatment. The dissolved minerals are water soluble minerals ions and thus more digestible for animals and fish. Example is carried out to show that acid So treatment of fish bones will separate collagenous protein from minerals present in the bones and that the liberated minerals are soluble in water. The collagenous proteins in l/} the residues may thereafter be treated to liberate and dissolve p,elatine to obtain improved binding capacity when used in a feed mixture.

Raw cleaned fish bones from salmon were added 3 parts water and ', part 36% s hydrochloric acid. The mixture was stinted cautiously for 13 hours at 10 C. The water soluble please was separated by sieving Table 4 shows the chemical composition of the bone raw material, the water phase and bone residues. The bone residues were washed times with equal amounts of water.

O Table 4.

Chemical composition of bone aw material and fractions after acid treatment.

The values are given as drv matter in kilograms in the experiment.

matterProtein | Ash Calcium Phosphorus Bone raw 4.70 1.5 2.18 ().78 O. lo material I l | l Water phase '.61 0.()5 1 l.SO 0.5: OHS Residue 1.1 1 1. 2S 0.07 0.0 0.01 The experiment shows clearly that bone proteins that are separated from the minerals as proteins are present in the undissolved residue Nvhile the minerals me present in the water phase. By the process according to the present invention the minerals originally present in the bones are made more soluble and thus more digestible. At the same time bone collagen is isolated and may be treated for liberation of soluble gelatine that may be utilised to improve binding capacity in feeds and fish products.

Claims

C L A I M S

I. A process for improving the biological digestibility of a feed product made of a raw material comprisin, as a minor or substantial fraction of bone tissues characterized in that the ram material is subjected to an acid or alkaline treatment wherein the minerals in the bone tissue are made soluble.

2. A process in accordance with claim 1, characterized in that the acid treatment is conducted by the addition of hydrochloric acid.

3. A process in accordance with claim 2, characterized in that the concentration of said acid is 0.1 to 10 M, preferably 0.5 to 3M.

4. A process in accordance with one of the claims I - 3, characterized in that the minerals from bones are made soluble in a processing step conducted as part of the conventional manufacturing of a feed product.

5. A process ha accordance with one of claims I - 3, characterized in that a fraction containing the minerals made soluble is added as an ingredient to a feed product.

6. A process in accordance with one of the claims 1-5, characterized in that said bone tissue comprises fish bones.

7. A process in accordance with one of the claims 1-6, characterized in that the raw material is further subjected to a process for gelatine liberation.

8. A process in accordance with one of the claims 1-7, wherein the binding capacity of a fish product is also improved, characterized by that a collagen and bone tissue comprising raw material is subjected to a process step wherein the gelatine present in the collagen comprising fish material is liberated, and that the gelatins is then used subsequently in the production of the fish product.

9. A process in accordance with claim 8, characterized by that the process step wherein the gelatine present in the collagen comprising fish material is liberated is a physical and/or chemical conversion of the dissoluble collagen present in the collagen comprising fish material to a soluble gelatins material.

10. A process in accordance with cloths 8, characterized by that the process step wherein the gelatine present in the collagen comprising fish material is liberated is carried out by adding an aqueous solution to the fish material where the ratio of fish material to water is in the range of 1:10 to 1:1, preferably 1:5 to 1:2' most preferably about 1:3, based on weight/weight; followed by heating of the fish material and the solution to at least 50 C for at least 3 hours, for repeated or continuous extraction.

11. A process in accordance with claim 8, characterized in that raw material receives a greater temperature load than a load equivalent to 90 C for more than 40 minutes, and that hot stickwater is used to extract gelatine from the collagen source.

12. A process in accordance with any one of claims 8-1 1, characterized by that the process step wherein the gelatine present in the collagen comprising fish material is liberated is included in the conventional processing of a fish material to fish meal product, a feed product' or a fish product for human consumption, such as for example fish forcemeat, fish balls or fish cakes.

13. A feed product with improved biological digestibility, characterized in that the product is manufactured from raw material comprising a minor or substantial portion bone tissue, where the raw material is subjected to an acid or alkaline treatment wherein the minerals ha the bone tissues are made soluble.

14. A product according to claim 13, with improved binding capability and biological digestibility, where the raw material is subjected to the acid or alkaline treatment wherein the minerals in the bone tissues are made soluble, and to a process for gelatine liberation.

15. A product in accordance with one of the claims 13 - 14, characterized in that said product is manufactured by a process according to one of the claims I - 12.

16. Use of a product in accordance with claim 15, characterized by that the product is used as a supplement ingredient in the manufacturing of pharmaceutical, veterinary, food or cosmetic products.

17. A process for improving the biological digestibility of a feed product substantially as hereinbefore described.

18. A feed product with improved biological digestibility substantially as hereinbefore described.

19 A process for improving the binding capability of a fish material, characterized in that collagen containing fish material is subjected to a gelatine liberation step in order to improve the inherent binding capability of said fish material.

20. A process in accordance with claim Is,characterized in that the collagen containing fish material is selected from the group comprising connective tissues, skin lo and bones from fish.

21. A process in accordance with clainl9, characterized in that said fish materiel is selected *tom the group comprising al bone from fish by-products. b) sl; in from fish by- producrs, c) whole fish for processing to feed, d! whole fish for processing to teed ingredient and e) bone containing intermediate products from fish meal processing.

22 A process in accordance with claim 19, characterized in that said gelatine liberation step is a physical and/or chemical conversion of insoluble collagen in said collagen containing fish material to a water soluble gelatinous material. lo

23. A process in accordance with claim 19,characterized in that the gelatinous material is not isolated or e.;tracted from the fish material.

24. A process in accordance with claim Characterized in that the gelatine 2s liberation step is conducted by adding an aqueous liquid to the fish material, and thereafter heating the mixture of fish material and liquid to at least 50 C for at least 3 hours.

A process in accordance with claim 24,eharacterized in that the gelatine liberation step is conducted by heating the mixture at about 1 00 C. i

26 A process in accordance with clairr. 24, characterized in that the gelatins liberation step is conducted by heating, Else;nh;tlre in about 10 hours.

27. A process in accordance fitly claim 24. characterized in that the ratio of fish material to water is in the range of 1:10 to 1: 1, preferable 1: to 1:. most preferable about 1:3, based on weight'weight.

28. A process in accordance with claim 22, characterized in the liberation of gelatine is conducted by high pressure cooking.

29.t process in accordance with Claire. 22, hacterized in that the liberation of _eiatine Is conducted by repeated or continuous extraction by hot processing.

30.- process in accordance avid claim 22, naracterized in that the liberation or is palatine is conducted by repeated or continuous extraction by hot stickvater from the fish meal processing.

3 1. process in accordance with one of the preceding claims, characterized in that stud elat.ne liberation step is included in the conventional processing of a fish material So to a fish meal product.

32. -\ process in accordance with one of the preceding claims, characterized in that said gelatine liberation step is included in the conventional processing of a fish material to fish feed product.

33. .\ process in accordance with one of the preceding claims, characterized in that said gelatins liberation step is included in the conventional processing of a fish material to a fish product for human consumption such as for instance fish forcemeat. fish balls or fish castes.

4. process for improving the biological digestibility of a feed product made of a ram- nateial comprising as a minor or substantial fraction of bone tissues. characterized in that the raw material is subjected to a process of for gelatine liberation wherein the proteins in the bone tissue are made digestible.

3s process for improving the biological digestibility of a feed product made of a ran material comprising as a minor or substantial fraction of bone tissues, characterized in that the raw material is subjected to a process of acid or alkaline treatment wherein minerals in the bone tissue are made soluble.

36. process in accordance with claim 35. characterized in that the treatment is conducted by the addition of hi drochloric ac d.

37 process in accordance with claim 36, characterized in that the concentration of i said hydrochloric acid is 0.1 to 1(1 al, preferable 0 to Mel.

38 BY process in accordance With one of the claims 35-37, characterized in that the solubili,.rion ot minerals from bones are conducted as a process step in the process line of a conventional manufacturing of a feed product. to

39 -\ process in accordance with one of the claims 35-37, characterized in that a fraction containing soloubilized minerals is added as an ingredient to a feed product.

4 ;\ process in accordance with one ofthe claims 35-39, characterized in that said bone tissue is fish bones.

I. process for increasing the binding capability and the biological digestibility of a product, characterized in that a collagen and bone tissue containing raw material is subjected to both a gelatins liberation step in order to improve the inherent binding capability and a process of acid or alkaline treatment u herein minerals in the bone tissue are made soluble.

42.\ process in accordance with claim. 4l, characterized in that a process according to one o- the claims lo lo 34 is used in combination with a process according to Clairol 35 to 39 43 A process in accordance with one of the claims 40 Add ill, characterized in that :he collagen and bone tissue containing raw material is a tush material 44 A process in accordance with one of the claims 40-43. characterized in that raw lo material get a higher temperature load than equivalent to 90 C in more than 40 minutes, and that a hot processing liquid is used to extract gelatine from the collagen source.

45.\ product with improved binding capability and biological digestibility.

characterized in that the product is manufactured of a collagen and bone tissue containing raw material which is subjected to both a palatine liberation step in order to improve the inherent binding capability and a process of acid or alkaline treatment wherein minerals in the bone tissue are made soluble.

46.5L product in accordance with claims 4s, c;..racterized in that the collagen and Do bone tissue containing, raw material is a fish material.

47.\ product in accordance with one of the claims 4s or 46, characterized in that said product is manufactured by a process according to one of the chains 19 to 34 in combination with a process according to claim 35 to 39 48 A product in accordance with one of the claims 45-47, characterized in that the product is used as a supplement ingredient in the manufacturing of pharmaceutical, veterinary. food and cosmetic products