RU2786666C1 - Protein feed supplement for industrial aquaculture - Google Patents

Abstract

FIELD: fodder production.

SUBSTANCE: invention relates to the field of fodder production, in particular to compound feed intended for feeding artificially grown valuable fish species. Protein feed additive includes fish meal and fish protein hydrolyzate. Fish protein hydrolyzate is obtained by processing smoked fish heads at 130-140°C for 1 hour. The quantitative ratio of components in the additive, wt.%: fish meal 85-95, fish protein hydrolyzate 5-15.

EFFECT: invention provides an increase in the digestibility of the feed and the duration of its storage.

1 cl, 1 tbl, 1 ex

Description

The invention relates to the field of fodder production, in particular, to feed intended for feeding artificially grown valuable fish species (salmon, whitefish). At the same time, one of the main problems of aquaculture associated with the quality of feed in terms of storage stability against oxidative and bacterial spoilage is solved, as well as the task of partially replacing scarce feed fishmeal in compound feeds with a highly digestible peptide additive of “fish origin”.

The protein feed additive is intended to be introduced into the compound feed for industrial aquaculture, mainly salmon and whitefish grown under artificial conditions, as a source of highly digestible and physiologically active low molecular weight peptides with antioxidant and antiseptic properties.

The composition of feed for fish is known (RU 2579767, IPC A23K 50/80, A23K 10/30, A23K 10/20, A23K 20/174, publ. 10.04.2016), characterized by the fact. that the protein component is green protein concentrates (6.6-8.25), fish meal (11.7-24.0), meat and bone meal (1.6-7.0), yeast (7.4-10 .0), sunflower cake (18.0-30.0), soybean meal (15.8-22.0) Wheat flour 10.6-14.6 Vitamin B-4 0.17-0.45 Premix 0, 18-0.45 Sunflower oil 4.35 -7.0.

However, in this case, the protein component is formed by many components of non-fish nature, including vegetable origin (meat and bone meal, yeast, sunflower cake, soybean meal), the protein of which is considered defective and does not meet the amino acid balance requirements for feed for salmon and whitefish, in which the maximum content should be the proportion of fish protein. When varying these protein components within the indicated intervals, it is very difficult to ensure a stable quality of the protein in terms of its quantity and amino acid balance. At the same time, sunflower cake and soybean meal necessarily contain associated fats (oils) that are not stable in storage, which will worsen the balance of feed in terms of the ratio of "proteins: fats" and the storage capacity of the resulting feed due to the rapid oxidation of lipids. Due to the lack of components with antioxidant and antiseptic properties, these feeds are not stable during storage, quickly oxidize and bacterially deteriorate.

Known granulated feed for aquaculture (RU 2696545, IPC A23K 50/80, A23K 40/10, A23K 10/30, A23K 20/158, A23K 20/174, publ. 02.08.2019), containing cake as a protein additive sunflower meal, fish meal, fodder yeast, crushed gammarus, brewer's grains and flaxseed meal at specified ratios.

The disadvantage of this additive is its multicomponent nature and the instability of the chemical composition of each component. At the same time, the share of the main fish component - fish meal - is only 20-40%, and the addition of crushed gammarus crustacean in the amount of 15% does not solve the problem of protein nutrition of salmon and whitefish. The addition of brewer's grain proteins in the amount of 3-5% will significantly complicate the process of assimilation of protein components of food, since brewer's grains contain cellulose that is difficult to digest (about 27%) and a protein component that is poorly digested by such "predatory" fish species as salmon and whitefish, which need, first of all, not in “vegetable”, but in “fish” protein. The disadvantage of the composition of this additive is also instability during storage due to the lack of substances with antioxidant and antiseptic properties that would protect the fatty fraction (fish oil, palm oil, gammarus fat) from rancidity, and the protein component from bacterial spoilage.

A known method for the production of feed compositions (RU 2708923, IPC A01K 61/00, A23K 10/00, publ. 12/12/2019) for sturgeon and salmon. obtained by dry pressing, dry components according to the recipe, in which, as a partial replacement for fish meal and other sources of animal protein, the hydrolyzate of carcasses of fur animals (GTPZ) is introduced.

The disadvantage of this composition is the presence of a hydrolyzate of carcasses of fur-bearing animals, which differs significantly in the amino acid composition of proteins from the desired composition and the ratio between them. The standard of amino acid balance for salmon feed is fishmeal protein. However, in the carcasses of fur-bearing animals, not only muscle mass is hydrolyzed, but also bones, skin and fur, containing specific metalloproteins and keratin proteins, consisting of amino acids, practically indigestible by salmon and whitefish. In addition, the hydrolysates of carcasses of fur animals are characterized by high fat content, which will definitely introduce an imbalance in the ratio of the main components of animal feed (proteins: fats: carbohydrates). At the same time, it is important that the main fat component in these compound feeds should be fish oil, and not animal oil, which differs in its fatty acid composition. Increasing the fat content of mixed fodders will also reduce their storage capacity. It should also be noted that with the introduction of GTPZ, the very method of obtaining feed by dry pressing will be difficult, since hydrolysates will be poorly extruded due to high fat content and moisture and provide the specified dimensions and other physicochemical characteristics of the granules. The disadvantage of the composition of this composition is also the absence of substances that cause stability in storage, with antioxidant and antiseptic properties.

The closest technical solution is a protein feed additive for juvenile fish (RU 2479215, IPC A23K 1/00, A23K 61/00, publ. 20.04.2013). including fish meal and fish protein hydrolyzate containing polypeptides with a molecular weight of 1000 - 1300 Yes in the following ratio, wt. %: fishmeal 80-84: fishmeal hydrolysate as 16-20.

However, the feed additive obtained in this method is not highly digestible, since the resulting polypeptides have a fairly high molecular weight (MW) of 1000 - 1300 Da, which indicates that they consist of more than 100 amino acids, which requires their preliminary cleavage to amino acids in the stomach and fish intestines. At the same time, this hydrolyzate does not stimulate the formation of additional gastric juice, since it does not have an attractive odor. It is important that various parts of fresh, chilled or frozen fish (innards, heads, ridges, etc.) are used as fish waste, and their hydrolysis is carried out using proteolytic enzymes. In this case, after the process, the yield of a water-soluble hydrolyzed mass, including low molecular weight peptides, is only 10-20% of the mass of the raw material. At the same time, more than 80% of the remaining mass of raw materials, which is a valuable organic composition in the form of a mixture of high-molecular protein, fat and protein-mineral compounds, which are not used as part of the protein supplement. It is important that the final protein supplement containing fishmeal oil, which is characterized by rapid oxidation, is not stable during storage, while the reduced storage capacity is also enhanced by the addition of low molecular weight polypeptides, which are an excellent nutrient medium for putrefactive and pathogenic microorganisms.

The invention solves the problem of improving the quality of the feed protein additive for industrial aquaculture, increasing the digestibility of the feed and the duration of its storage, through the use of smoked fish heads and obtaining a hydrolyzate in the given parameters.

To obtain the required technical result in a protein feed additive for industrial aquaculture, including fish meal and fish protein hydrolyzate, it is proposed to obtain fish protein hydrolyzate by processing smoked fish heads at 130-140°C for 1 hour, and the quantitative ratio of the components in the additive is proposed to be taken , wt. %: fish meal 85-95, fish protein hydrolyzate 5-15.

The claimed invention solves the problem of creating a high-quality feed protein supplement for industrial aquaculture, which has increased digestibility and shelf life due to the enrichment of feed with highly effective low molecular weight di-, tri- and oligopeptides (including no more than 10 amino acid residues) of "fish" origin, having high digestibility and antioxidant and antiseptic properties. The indicated properties of the protein additive and feed for aquaculture are due to the choice of smoked fish heads as raw materials and hydrolysis by high-temperature treatment at 130-140 ° C for 1 hour, followed by mixing fish meal and hydrolyzate of smoked fish heads in a ratio of 85-95: 5-15 . The increased digestibility of the resulting peptides is due to the very low molecular weight of the resulting peptides (less than 1000 Da), which became possible precisely with such hydrolysis parameters. The antioxidant and antiseptic properties of the resulting peptides are due to the formation of a new chemical nature in them due to chemical addition at high temperatures to the functional groups of amino acids of aromatic smoke components found in smoked fish heads, with the formation of phenolpetides with pronounced antioxidant and antiseptic effects.

EFFECT: invention makes it possible to obtain natural feed protein supplements of "fish" origin that best meet the physiological needs of salmon and whitefish grown in industrial aquaculture, while improving the digestibility of the supplement due to the very low molecular weight (MW) of the introduced peptides (MW less than 1000 Da), which has a positive effect on the absorption of components, metabolic metabolism, growth and hematological parameters of the body. Targeted protein supplement, consisting mainly of proteins (60-70%) and lipids (5-15%) of fishmeal, which are capable of quickly bacterial contamination and oxidization with the formation of harmful and toxic compounds, when enriched with low molecular weight peptides obtained from smoked fish heads , increases its storage stability due to low molecular weight peptides, which are effective antioxidants and antiseptics as a result of chemical addition of aromatic smoke components. Such peptides (phenolpeptides) are able to interact with peroxide and hydroperoxide radicals of fishmeal fat and prevent their further oxidation. They also suppress the development of pathogenic and putrefactive microflora, molds and yeasts, which are potentially possible in the target protein supplement. As a result, the storage stability of the protein supplement and the entire feed is increased, as well as its shelf life.

The method is carried out as follows. Fish meal that meets the requirements of GOST 2116-2000 “Fodder meal from fish, marine mammals, crustaceans and invertebrates. Specifications”, mixed with dry hydrolyzate of smoked fish heads, consisting of low molecular weight peptides with MW less than 1000 Da, obtained by high-temperature treatment of smoked fish heads at 130-140°C for 1 hour. The hydrolyzate is a free-flowing powder with a natural smell of dried fish and a slight smoked aroma. These two products (fish meal and hydrolyzate of smoked fish heads) are combined in the ratio of mass parts, respectively, 85-95 and 15-5 and thoroughly mixed. The finished protein supplement has the form of a dry powder with a natural fishy smell, without a hint of smoke and is stored for 1.5-2.0 years without signs of deterioration (against 1 year of storage of fodder fishmeal and supplements with fish protein hydrolyzate in the prototype). During storage, the protein supplement is not affected by pathogenic bacteria, does not undergo negative lipid oxidation. This protein supplement is intended for adding salmon and whitefish to mixed feed along with other components when grown under artificial conditions of industrial aquaculture. Its introduction in the future in the amount of 60-80% will contribute to a significant improvement in the quality of fish feed for aquaculture by increasing its digestibility and shelf life.

This goal is achieved by acquiring the desired properties from the hydrolyzate of smoked fish heads introduced into the fishmeal. This hydrolyzate is produced by exposure to high temperatures of 130-140°C on crushed smoked fish heads in an aquatic environment, as a result, head proteins (mainly collagen and ossein) undergo thermal destruction (thermohydrolysis) with the formation of low molecular weight peptides with a molecular weight (MW) of less than 1000 Da . The subsequent separation of the peptide water-soluble mass by centrifugation from other organic fractions (fat and mineral) allows you to collect and concentrate the peptide material. Further, the hydrolyzate is dehydrated by freeze-drying and crushed, as a result of which it acquires flowability and the natural smell of dried fish with a slight aroma of smoked meat.

The antioxidant ability of the smoked fish hydrolyzate is due to the fact that the resulting peptides with a molecular weight of less than 1000 Da (di-, tri-... ring). Chemical bonds are formed as a result of ionic interaction of functional groups of basic amino acid residues of oligopeptides of smoked fish hydrolysates (carboxylic, carbonyl, amine, thiol groups and peptide bonds) and hydroxyl and carboxyl groups of smoke aromatic compounds (guaiacol, syringol, pyrocatechol, benzoic acid, salicylic acid and etc.). The resulting derivatives (phenolpeptides) have free OH groups on their surface, which are excellent "plugs" for peroxide and hydroperoxide radicals in fats, interacting with which they prevent chain oxidative reactions and stabilize the quality of the lipid fraction. Simultaneously formed phenolpeptides exhibit bactericidal and fungicidal activity, suppress pathogenic microflora, yeasts and molds. This property is due to their solubility in lipids of microorganisms, which causes their plasmolysis. As a result, the hydrolyzate of smoked fish heads acquires pronounced antioxidant and antiseptic properties, which, when mixed with fishmeal, provide increased storage stability in the resulting protein supplement. The shelf life of the protein supplement obtained under these parameters is 1.5-2.0 years, while fishmeal (and protein feed additive - prototype) is stored for no more than 1 year.

The high digestibility of the hydrolyzate of smoked fish is due to their low molecular weight - less than 1000 Da (less than 1 kDa), which is comparable to the pore sizes in the intestinal membranes of fish. Due to their small mass, the peptides do not stay in the stomach of fish, they immediately enter the intestines, where they are directly absorbed into the bloodstream by means of membrane digestion without pre-treatment with enzymes, which is required for high-molecular peptides and proteins. As a result, the blood is saturated with protein components faster, better transfers nutrients, oxygen, metabolic products, which is reflected in a more accelerated weight gain in fish, an increase in their survival in artificial conditions, and improved hematological blood parameters. When mixing the hydrolyzate of smoked fish with fishmeal in the indicated ratio, there is a significant increase in the digestibility of the feed additive in the compound feed, reflected by the values of the feed coefficient (the ratio of feed consumed to the mass of fish), as well as an increase in the values of growth and hematological parameters of fish.

The target characteristics of the quality of the feed protein additive are acquired from it when obtaining a hydrolyzate of fish protein from smoked fish heads with the specified parameters of thermal hydrolysis and by mixing fish meal with this hydrolyzate in a given ratio.

When implementing the method with other parameters than those indicated in the formula, the purpose of the invention is not achieved.

Upon receipt of a hydrolyzate from smoked fish heads by high-temperature treatment for 1 hour at a temperature of less than 130°C, the resulting composition of peptides will have a molecular weight of more than 1000 kDa, which will make it difficult to absorb them in the intestines of fish, reduce the digestibility of the feed protein supplement, while antiseptic and antioxidant properties they do not appear in it, since smoke aromatic components cannot be chemically fixed on the functional groups of peptides due to their low hydrolysis temperature, which is insufficient for the addition reaction to form phenolpeptides. The shelf life of such an additive is less than 1 year. The purpose of the invention is not achieved.

Upon receipt of low molecular weight peptides from smoked fish heads by high-temperature treatment for 1 hour at a temperature of more than 140°C, the resulting composition of peptides will be represented not by peptides, but by free amino acids and their decay products - biogenic amines, ammonia, mono-, di-, trimethylamines, which have toxic effects. The digestibility of the feed additive and feed is thus reduced, while it becomes potentially toxic. It is important that the antiseptic and antioxidant properties of this protein supplement will be absent, since under these regimes of thermohydrolysis, with deep destruction of all tissues of smoked fish heads, smoke aromatic components themselves undergo thermal destruction and lose their chemical nature. As a result, the shelf life of the additive will be less than 1 year. In this case, the organoleptic properties of the hydrolyzate deteriorate, an unpleasant chemical odor appears (ammonia and products of destruction of aromatic substances). The purpose of the invention is not achieved.

When preparing a feed protein supplement by mixing less than 85% fishmeal and more than 15% smoked fish head hydrolyzate in the finished protein supplement, the smoked flavor will be too pronounced, which somewhat scares away the fish due to its uncharacteristic for fish feed. In this case, the absorption and, as a result, the digestibility of it decreases, and the purpose of the invention in this part of improving the quality of the additive is not achieved.

When preparing a feed protein supplement by mixing fishmeal in an amount of more than 95% and a hydrolyzate from smoked fish heads less than 5%, the amount of active peptides with a molecular weight of less than 1000 Da, carrying smoke components with antioxidant and antiseptic properties (phenolpeptides), will be less than a statistically significant value , less than which antioxidant and antiseptic properties in relation to the contained fat and proteins of fodder meal contaminated by microorganisms do not appear. As a result, no increase in the digestibility of the target product is observed, and the shelf life of the additive will be less than 1 year. The purpose of the invention is not achieved.

Description of a specific example of the implementation of the method.

Example 1

90 kg of fish feed meal is mixed with 10 kg of dry hydrolyzate obtained by high temperature treatment of smoked fish heads at 135°C for 1 hour and consisting of peptides with a molecular weight (MW) of 700 Da. The mixture is thoroughly mixed in a mixing drum of the "drunken barrel" type. The target protein supplement is a free-flowing powder with a specific smell of dried fish without a smoked flavor.

Fishmeal has a chemical composition (in%) containing protein, fat, minerals and water, respectively 62; 12; fourteen; 12. The hydrolyzate from smoked fish heads has a chemical composition (in%) containing protein, fat, minerals, water, respectively 82.7; 2.0; 8.6; 6.7. When mixing fishmeal and hydrolyzate in a ratio of 9:1 with the target protein supplement has the following chemical composition (in%): the content of protein, fat, minerals and water, respectively, 67, 10, 13, 10. At the same time, the target supplement contains about 8 3% of the mass of low molecular weight peptides with an MM of 900 Da, which have an increased antioxidant activity (AA), since during the period of hydrolysis at a given temperature they turned into the form of phenolpeptides. When assessing their antioxidant activity (AA) according to the method of interaction with the DPPH radical, in the hydrolyzate of smoked fish heads, AA = 54.5%, in the target protein supplement when it is added to the standard feed for whitefish in the amount of 65%, AA = 13.1% . The effectiveness of the antiseptic activity of the hydrolyzate of smoked fish heads, determined by the indicator of the MIC (minimum inhibitory concentration that inhibits the visible growth of E. coli) is MIC = 1.1; the target additive has MIC = 4.6. The target protein supplement obtained with these parameters is stored without signs of spoilage for 1.8 years at normal temperature. Comparative feeding of whitefish fry with compound feed, which included a target protein supplement (versus feed with the addition of unsmoked fish protein hydrolyzate), for 56 days, digestibility by feed coefficient (CC - the ratio of the amount of feed eaten by fish to the increase in a unit mass of fish) when this additive was added to the composition of the standard feed in an amount of 65% for juvenile whitefish, it significantly increased (in the experimental batch of fish it was CC = 3.5 versus 3.8 in the batch with the control feed). At the same time, the growth rates of whitefish fry increased significantly: the survival rate (B) of fry increased by 8.3%, body weight gain (BW) - by 12.1%, specific growth rate (SGR) - by 3.95 g/cm.

The target parameters are achieved, the method according to these parameters is recommended. Other examples of the implementation of the method with possible combinations of parameters are shown in table 1.

The method provides for the production of a highly digestible protein feed additive for introduction into compound feed when growing industrial aquaculture (salmon, whitefish) as a source of physiologically active peptides with increased absorption, shelf life due to increased antioxidant and antiseptic properties.

The effectiveness of the method is due to the production of highly digestible low molecular weight peptide compositions from fish waste from smoke production, disposed by burial or incineration and not going for processing, which, due to the characteristics of the raw materials and the proposed processing parameters, have unique effects that are in demand in the production of feed products in fish farming.

For example, in the Kaliningrad region, about 80% of all Russian canned sprats in oil are produced from the Baltic sprat, while about 10 tons of smoked sprat heads are accumulated daily. The largest producers of sprats in the region “Fishing collective farm “ZA RODINU” and the fish canning complex of OJSC “RosKon” suffer losses of up to 30 million rubles. per year due to the need to dispose of waste - smoked sprat heads - as municipal solid waste, since there are still no ways to process smoked fish waste into demanded products.

On the other hand, fish farming is actively developing in Russia today, based on breeding fish in natural and artificial reservoirs using specialized feed, depending on the type of fish. One of the most promising and sought-after aquaculture objects are salmon and whitefish, which have high taste qualities. These species of fish are predatory, carnivorous, for their cultivation in feed, animal protein is needed, namely, fishmeal containing 50-60% of proteins. Unfortunately, in Russia, feed for these fish species is mainly imported. This is due to both the shortage of fishmeal in Russia and its insufficient quality from manufacturers, mainly the private sector. A large amount of smoked fish waste accumulates at operating fish processing enterprises, from which, using the proposed method, it is possible to obtain high-protein compositions that improve the quality of fishmeal in terms of digestibility and storage capacity, which determines the effectiveness of the application of this invention.

The present invention is easily implemented in terms of processing smoked fish heads to obtain low molecular weight compositions in the indicated modes. For this, a thermal hydrolyzer is used, in which it is possible to reach temperatures of 130-140°C, which are rational for the destruction of the organic components of this raw material with the release of the protein fraction in the form of peptides with a molecular weight of less than 1000 Da. Such processing is much more efficient than the enzymatic hydrolysis of this raw material, since in the latter case expensive enzymes and special fermenters are required for the implementation of the process, while the process follows a decaying trajectory due to the consumption of the enzyme, and the fermented hydrolyzate is quickly contaminated with microorganisms, tk. it does not undergo heat treatment. In this case, the yield of the hydrolyzate is not more than 10% of the mass of raw materials, and the rest of the waste is not used. It is also important that during the fermentation of smoked fish heads, this process would not give more than 5% hydrolyzate yield, since smoked fish proteins are hardly accessible to enzymes due to the presence of smoke components, and a large number of bones in fish heads cannot be enzymatically hydrolyzed at all. When using the high-temperature method of hydrolysis of smoked fish heads according to the specified parameters, the raw material is completely hydrolyzed to a homogeneous suspension, from which the protein fraction is separated, which is practically sterile, since the process took place at a high temperature. This hydrolyzate after drying is added to the fishmeal in the indicated dosages to obtain a highly effective protein feed additive.

Technological experiments on the storage capacity of the proposed feed additive indicate its increased storage stability, and biological tests in the composition of feed for whitefish fry showed its high physiological efficiency in terms of digestibility.

The method is cost-effective, cost-effective and profitable, allows you to produce popular and useful feed products that are affordable for many fish farms. The introduction of the method will allow developing a high-tech aquaculture sector in the fishing industry, making fish-smoking and fish-canning production waste-free, not having problems with smoking waste, creating new jobs, replacing imported fish additives in compound feeds with domestic feeds, making feed available to many fish farms, and fish - accessible to many socially significant segments of the population with a low level of income (pensioners, the disabled, teenagers, large families, etc.).

Claims (1)

Protein feed additive for industrial aquaculture, including fish meal and fish protein hydrolyzate, characterized in that the fish protein hydrolyzate is obtained by processing smoked fish heads at 130-140°C for 1 hour, and the quantitative ratio of the components in the additive is, wt. %: fish meal 85-95, fish protein hydrolyzate 5-15.