Method for obtaining feed additive cryoconcentrate from mushroom mass for farm animals

Abstract

FIELD: feed production.SUBSTANCE: invention relates to a method for producing a feed additive from mushroom mass for farm animals. The method is characterized in that it includes preliminary cutting of fruiting bodies of mushrooms selected from the species Agaricus bisporus, Pleurotus ostreatus, Ganoderma lucidum, or a mixture of two or more of the specified mushroom species into slices with a thickness of 3 mm to 7 mm, placing the resulting slices of mushroom mass in bulk on perforated stainless steel trays measuring 500×1000 mm, with a layer thickness of no more than 15 mm, placing trays on racks with a gap between trays of at least 60 mm, a total length of the drying corridor of no more than 2000 mm, and drying the mushroom mass in a condensation drying chamber at an air temperature of no more than 28 °C and dew point 6 °C for 14 hours until the moisture content stabilizes, grinding the dried biomass in a liquid nitrogen environment, followed by heating to ambient temperature, conditioning the product for at least 1 hour at room temperature, sifting through a sieve with a mesh size of 150 mcm and packing the resulting finely dispersed powder into sealed bags with vacuuming and gas substitution with argon.EFFECT: increased bioavailability of biologically active substances and nutritional components, an extended shelf life without loss of beneficial properties, and improved homogeneity.1 cl, 2 tbl

Description

[0001] The invention finds application in the production of functional feed additives with high biological activity, designed to improve the health, productivity, and sustainability of farm animals and poultry. The technical solution ensures the effective preservation of the bioactive components of fungal biomass through low-temperature drying, cryogenic grinding, and packaging in a protective gas environment, improving the quality and shelf life of the feed additives. The claimed method relates to biotechnology and agriculture, with a deep technological focus on the production of high-quality feed additives based on fungal biomass.

[0002] Chitin in birds actually behaves as an indigestible fiber. Chitin has long been considered an indigestible dietary fiber in animals (E. Tabata, A. Kashimura, S. Wakita, M. Ohno, M. Sakaguchi, Y. Sugahara, Y. Kino, V. Matoska, P. O. Bauer, F. Oyama. Gastric and intestinal proteases resistance of chicken acidic chitinase nominates chitin-containing organisms for alternative whole edible diets for poultry. 2017. URL: https: / / pubmed.ncbi.nlm.nih.gov / 28751762 / ). Experiments with broiler chickens showed that when pure chitin (25-75 g / kg) was included in the diet, the apparent digestion of the protein fraction of chitin was only ≈ 45-50%. This means that more than half of the chitin passes through digestion with virtually no absorption.Reviews also indicate that even with acid chitinase (Chia) in the crop of hens, the overall digestibility of chitin remains limited: with high inclusion of feed containing chitin (e.g., from 15% to 100% insects), a sharp increase in the viscosity of the intestinal contents and a decrease in the digestibility of dry matter and protein are observed (Linda Abenaim, Barbara Conti. Harnessing Chitin from Edible Insects for Livestock Nutrition. 2025. URL: https: / / www.mdpi.com / 2075-4450 / 16 / 8 / 799 / ). Thus, several studies have confirmed that farm birds poorly digest chitin and have difficulty hydrolyzing it.

[0003] Chitin is an inert polymer. It is insoluble in water and acids and, in fact, becomes a structural component of food, similar to fiber (Razdan, Alexander & Pettersson, Dan. Effect of chitin and chitosan on nutrient digestibility and plasma lipid concentration in broiler chickens. The British journal of nutrition. 1994. 72. 277-88). Because of this, without special processing, chitin is almost a source of nutrients: pure chitin provides only ≈8-9 MJ of metabolizable energy per kg (about 2-3 kcal / g) and is poorly digestible. Only with external enzymatic processing does its nutritional value increase significantly. For example, Hossain and Blair showed that adding chitinase to feed increased the energy value of chitin and increased the true digestibility of chitin protein to ~87% (versus ≈50% without the enzyme) (Hossain SM, Blair R. Chitin utilisation by broilers and its effect on body composition and blood metabolites. Br Poult Sci. 2007. URL: https: / / pubmed.Without such processing, birds are unable to effectively break down the chitinous shell and extract the nutrients (proteins, carbohydrates, minerals) contained within.

[0004] To increase the bioavailability of the nutritional and biologically active components of mushroom raw materials, processing methods that destroy the mushroom cell walls are used. These methods include mechanical grinding, micronization, extrusion, and other techniques aimed at weakening the chitin-glucan framework, which increases the availability of nutrients for enzymatic action in the gastrointestinal tract of farm animals and poultry.

[0005] A patent is known from the prior art, which describes a feed additive from the bran of the Pleurotus citrinopileatus mushroom for birds and a method for preparing it (patent CN 106260707, A23K 10 / 18, A23K 10 / 30, A23K 10 / 37, A23K 20 / 163, A23K 20 / 28, A23K 50 / 75, published on 04.01.2017). A feed supplement for poultry made from the bran of the Pleurotus citrinopileatus mushroom contains 20-30 parts of the bran of the Pleurotus citrinopileatus mushroom, 5-8 parts of tea cake, 3-5 parts of garlic powder, 1-2 parts of milk vetch, 1-2 parts of the rhizome of the large-headed atractylodes, 0.2-0.4 parts of medicinal stone, 2-2.5 parts of brown sugar, 0.1-0.15 parts of dry yeast and 40-50 parts of water.According to the invention, fermented bran of the Pleurotus citrinopileatus mushroom is taken as the main raw material, wherein the raw material from the bran of the Pleurotus citrinopileatus mushroom contains much more mycelium and has an aromatic smell of an edible mushroom and excellent taste; the bran of the Pleurotus citrinopileatus mushroom taken according to the invention contains various active pullulans and has an effect on maintaining healthy energy and enhancing immunity.

[0006] A disadvantage of the known analogue is that the patent uses a feed additive made from the husk of the yellow fly agaric with the addition of many components (tea leaves, garlic powder, astragalus, etc.), which complicates the composition and can increase the cost and technological complexity of production compared to the proposed method for obtaining concentrated mushroom biomass.

[0007] A method for producing a functional feed additive for geese with the addition of marsh oyster mushroom is known from the prior art (patent TWI 820878, A23K 10 / 12, A23K 50 / 75, published on 01.11.2023). The method comprises the following steps: grinding the roots of king oyster mushroom with sawdust; sterilizing the obtained roots of king oyster mushroom; implanting saccharomyces into the sterilized ground roots of king oyster mushroom obtained in the previous step to carry out the first fermentation; implanting lactobacilli into the product of the first fermentation obtained in the previous step to carry out the second fermentation; and drying the product of the second fermentation obtained in the previous step with cold air as a functional feed additive for geese with a moisture content of no more than 20 wt.%. The present invention also provides a method of using a feed additive for geese, i.e. adding the feed additive to goose feed in a ratio of 2% to 6% by weight.

[0008] The disadvantage of the well-known analogue is that it uses a two-stage fermentation process, including the introduction of yeast and lactic acid bacteria, which lengthens the technological process and requires strict control of fermentation conditions. The analogue is focused only on functional feed additives for geese.

[0009] A known method for preparing an animal feed additive using mushroom residues and an animal feed additive as raw materials is (CN Patent 108094733, A23K 10 / 12, A23K 10 / 30, A23K 10 / 37, A23K 20 / 195, A23K 20 / 26, A23K 50 / 15, A23K 50 / 30, published on June 1, 2018). The method includes the following steps: firstly, drying and grinding the Pleurotus ostreatus mushroom residue, adding water, mixing and leaching at a temperature of 20 to 25 °C to obtain a wet residue A and an extraction solution A; concentrating and drying the extraction solution A to obtain a low-temperature extract; secondly, adding water to the wet residue A, mixing and carrying out leaching at a temperature of 90 to 95°C to obtain a wet residue B and an extraction solution B; concentrating and drying the extraction solution B to obtain a high-temperature extract;third, adjusting the water content of the wet residue B, mixing the wet residue B with bran, urea and corn flour to obtain a fermentation nutrient medium; fourth, inoculating the mixed strain into the fermentation nutrient medium to obtain a fermentation product; fifth, mixing the low-temperature extract, high-temperature extract and fermentation product to obtain a feed additive.

[0010] The disadvantage of the known patent is that it uses multiple leaching of fungal biomass with dilution with water and high-temperature treatment (up to 90-95°C), which can lead to the loss of a significant portion of biologically active substances and a decrease in the quality of the final product.

[0011] A method for producing a biologically active feed additive is known (RU patent 2097979, A23K 1 / 00, published 10.12.1997). The feed contains biologically active substances and the biomass of somatic fungal structures formed during solid-state fermentation of feed grain. A fast-growing strain of basidiomycetes (Agricus bisporus) is used as the producer of biologically active substances. It is grown on a solid substrate (feed grain) for 5-7 days, followed by drying and milling of the biomass together with the substrate.

[0012] RU patent 2097979 utilizes mushroom biomass cultivation on a solid substrate (feed grain), while the claimed invention directly processes fresh mushroom biomass of Pleurotus spp. and Agaricus spp. without the substrate cultivation step. This may affect the composition and quality of the final product. Low-temperature drying with controlled dew point is omitted, which minimizes the loss of nutrients and biologically active components in the claimed method, improving the quality of the concentrate.

[0013] The technical result of the claimed invention consists in obtaining a cryoconcentrate of a feed additive from mushroom mass for farm animals with increased bioavailability of biologically active substances and nutritional components, an extended shelf life without loss of beneficial properties and improved homogeneity due to a combination of low-temperature condensation drying with dew point control, cryogenic grinding and packaging in a protective argon environment.

[0014] The problem is solved in that the method for producing a cryoconcentrate of a feed additive from mushroom mass for farm animals includes preliminary grinding of mushroom fruiting bodies with cutting into slices no more than 7 mm thick, placing the resulting mushroom mass in bulk on perforated stainless steel trays measuring 500 × 1000 mm, with a layer thickness of no more than 15 mm, with the possibility of overlapping up to 4 layers, placing the trays on racks with a gap between the trays of at least 60 mm, a total length of the drying corridor of no more than 2000 mm, drying the mushroom mass in a condensation drying chamber at an air temperature of no higher than 28 ° C and a dew point of 6 ° C for 14 hours until the moisture stabilizes, grinding the dried biomass in a liquid nitrogen environment, followed by heating to ambient temperature, conditioning the product for at least 1 hour at room temperature, sifting through sieve with a mesh size of 150 microns,packaging of finely dispersed powder in sealed bags with vacuuming and gas substitution with argon, or packaging of uncrushed material in sealed bags with modification of the environment to argon.

[0015] The initial mushroom mass is made from mushroom species selected from the group consisting of Agaricus bisporus, Pleurotus ostreatus, Ganoderma lucidum, or a mixture of two or more of the said mushroom species.

[0016] When using conventional drying methods, most biologically active substances (BAS) are destroyed by high temperatures. The drying process developed by the developed method does not require high temperatures, which allows for the preservation of all essential BAS in the biomass.

[0017] Most farm animals lack the enzymatic systems to completely break down chitin, which can limit the bioavailability of individual biologically active substances in fungal biomass without the use of specialized processing methods. Traditional grinding and crushing equipment cannot reduce the biomass to the required size to destroy chitin. A developed method using liquid nitrogen allows for grinding the biomass to particles as small as 150 microns, which disrupts the fungal cell wall and makes the biologically active substances more readily available for digestion by livestock and poultry.

[0018] The method for producing a cryoconcentrate of a feed additive from mushroom mass for farm animals includes the following steps:

[0019] 1. Preparation of source material.

[0020] The first stage involves pre-crushing the mushroom fruiting bodies and cutting them into slices no more than 7 mm thick. This ensures a sufficiently large surface area for effective drying and prevents oxidation of the internal structures through uniform moisture evaporation. Slice size is critical: if the thickness of the slices exceeds 7 mm, the center remains insufficiently dried, leading to a lengthy drying process and the risk of spoilage. If the thickness of the slices is less than 3 mm, excessive destruction of the cellular structures and loss of volatile components occurs.

[0021] 2. Placing biomass on carriers.

[0022] The resulting mushroom mass is placed in bulk on perforated stainless steel trays measuring 500 x 1000 mm in thickness, with a maximum layer thickness of 15 mm, and up to four layers can be stacked. The perforated design ensures drying air circulation from the bottom up, ensuring uniform drying of the entire mass. Stainless steel was selected to prevent metal oxidation and biomass contamination, which is critical when working with bioactive substances. The trays are placed on racks with at least 60 mm of clearance between them, ensuring free air circulation and preventing the formation of stagnant moisture zones. The total length of the drying corridor does not exceed 2000 mm, allowing for controlled microclimate conditions throughout the entire drying cycle.

[0023] 3. Low-temperature condensation drying.

[0024] The mushroom mass is dried in a condensation drying chamber at an air temperature no higher than 28°C and a dew point of 6°C for 14 hours until the moisture content stabilizes. Condensation drying (also known as adsorption drying) removes moisture through adsorption rather than evaporation, which is critical for preserving the heat-sensitive components of the biomass.

[0025] The temperature of 28°C is chosen as optimal for preserving the maximum amount of bioactive substances:

[0026] - Beta-glucans (β-glucans), the main immunomodulatory components of mushrooms, remain stable at this temperature;

[0027] - B vitamins contained in mushroom biomass are not subject to thermal degradation;

[0028] - Antioxidant compounds (polyphenols, ergoxanthine) are not oxidized;

[0029] - Enzymes potentially active in the digestive tract of animals retain their structure.

[0030] A dew point of 6°C ensures gradual moisture removal and a final moisture content of 10-12%, which inhibits microbial growth and ensures long-term product shelf life. Drying lasts 14 hours, with the first 4-5 hours actively removing free moisture, the next 6-7 hours removing bound moisture, and the final 2-3 hours ensuring moisture stabilization and equalization between the outer and inner layers of the biomass.

[0031] 4. Cryogenic grinding.

[0032] Dried biomass is ground in liquid nitrogen and then heated to ambient temperature. Cryogenic grinding is a critical step in the process:

[0033] - Destruction of chitin structures: Cryogenic temperature (-196°C) transforms chitin from a plastic to a brittle substance, allowing cell walls to be broken down to particle sizes less than 150 µm. At these sizes, bioactive substances (proteins, glucans, microelements) become more accessible for hydrolysis by endogenous enzymes in the gastrointestinal tract;

[0034] - Preservation of Volatile Components: Cryogenic grinding prevents the loss of volatile compounds (essential oils, volatile antioxidants) that are lost during mechanical grinding at room temperature;

[0035] - Oxidation prevention: Inert liquid nitrogen atmosphere prevents the oxidation of polyphenols and other reducing substances, which preserves the antioxidant potential of biomass.

[0036] 5. Product conditioning.

[0037] After cryogenic grinding, the product is conditioned for at least 1 hour at room temperature. This is necessary to equalize the temperature throughout the powder volume, remove residual liquid nitrogen, and stabilize the moisture content to an equilibrium level (~12%).

[0038] - Restoration of crystalline structures in biomass.

[0039] 6. Fractionation.

[0040] The ground material is sieved through a 150-µm sieve. This size is critical for bioavailability; particles of 100-150 µm provide maximum surface area for digestive enzymes to act upon, eliminate macroagglomerates that can hinder mixing with compound feed, and improve batch uniformity and reproducibility.

[0041] 7. Packed in a protective environment.

[0042] Fine powder is packaged in sealed bags under vacuum and gas substitution with argon. Alternatively, unmilled material can be packaged in sealed bags with an argon atmosphere.

[0043] Gaseous substitution with argon is necessary to create an inert environment that prevents the oxidation of bioactive substances, prevents the growth of microorganisms (lack of oxygen), and ensures long-term storage (shelf life of at least 24 months at a temperature of 2-8°C).

[0044] Examples of specific implementation of the invention are given below.

[0045] Example 1. Obtaining biomass from oyster mushroom (Pleurotus ostreatus)

[0046] Fresh oyster mushroom fruiting bodies were collected at the fully mature stage (cap diameter 40-60 mm). The initial moisture content of the fresh biomass was 92±1%.

[0047] 1. Preliminary preparation: fresh fruiting bodies are sorted by size, mechanically cleaned of substrate residues, cut into slices of 5±0.5 mm thickness using a wedge slicer, the yield of prepared material: 23 kg from 25 kg of original biomass (92% yield).

[0048] 2. Tray arrangement: The chopped biomass is placed on 4 perforated trays of 500×1000mm; layer thickness: 14mm; packing density: 1.1kg / m3 2 (taking into account the tray area); 4 trays measuring 500×1000 mm were used, stacked in a rack with a clearance of 70 mm between the trays, condensation drying.

[0049] Drying parameters: (air temperature: 26±1°C; dew point: 5.5±0.5°C; air circulation speed: 0.5 m / s; relative air humidity: 35±3%). Dry biomass yield: 2.3 kg (10% of the original wet biomass; dry matter yield coefficient of 10%).

[0050] 3. Cryogenic grinding

[0051] - Dry biomass (2.3 kg) subjected to cryogenic grinding;

[0052] - Liquid nitrogen exposure time: 5 minutes (optimal for complete freezing); grinding intensity: 3 cycles of a vibrating ball mill for 2 minutes; the yield of crushed material: 2.28 kg (99% yield, loss due to adhesion to the walls of the equipment).

[0053] 4. Air conditioning

[0054] - The crushed powder is left at a temperature of 20±2°C in a polyethylene container with the lid slightly open to remove residual liquid nitrogen;

[0055] - Duration: 1 hour;

[0056] - Humidity after conditioning: 12±1%.

[0057] 5. Fractionation

[0058] - The powder was sifted through a cascade of sieves with a mesh size of 150 microns, the powder was packaged in sealed polyethylene bags with a volume of 1000 g, vacuumed to 100 mbar;

[0059] - Oxygen replacement with argon (99.999% purity) - 2 filling and pumping cycles; final oxygen content in the package: < 0.5%; Heat sealing of packages.

[0060] Result:

[0061] - Finished product yield: 2.18 kg from 25 kg fresh biomass (8.7% yield);

[0062] - Packed: 10-11 bags of 200g;

[0063] - Output of useful components:

[0064] • Protein: ~32% of the original (losses during drying and cryogenic grinding);

[0065] • β-glucans: ~85% preserved (low temperature drying);

[0066] • Polyphenols: ~90% preserved (cryogenic grinding in an inert environment).

[0067] Example 2

[0068] Feeding application: Add to broiler feed at a dose of 1 kg / t (1000 g per ton). Based on the research objective, a research and production trial was conducted on Cobb 500 broiler chickens at the St. Petersburg State University of Veterinary Medicine (SPbSUVM) in accordance with the VNITIP methodology. The broilers were housed in cages. Each group consisted of 36 chickens, kept without separation by sex until 42 days of age, in compliance with all technological parameters.

[0069] The experiment on broilers was carried out according to the following scheme (Table 1).

[0070] Table 1. Scheme of the experiment on broiler chickens

[0071] Item No. Group Feeding Features 1. Control group Experimental diet (ED) according to the recommendations of VNITIP for the Cobb 500 cross 2. Experimental group Experimental group - OR + feed additive based on the biomass of fungi selected from the group* (1 kg / t of feed) *Additives were introduced into the compound feed using the step-mixing method

[0072] The birds were fed according to the recommendations for the Cobb 500 cross. For the first 7 days, the chicks received pelleted feed, followed by mash.

[0073] Research on broiler chickens shows the positive effect of adding mushroom biomass on the productive performance of broiler chickens.

[0074] Productivity indicators reflect the biological value and digestibility of nutrients (the preservation of protein and energy components of the supplement). Table 2 shows the performance indicators of chickens over a 42-day rearing period.

[0075] Table 2. Broiler productivity for 42 days of rearing, n=36

[0076] Indicator Control Experienced Safety, % 94 96 Initial live weight, g 43,52 ± 0,30 43,50 ± 0,30 Live weight on day 42, g 2309,22 ± 17,88 2377,39 ± 17,36* Gross gain in live weight, g 2265,69 ± 17,94 2333,89 ± 17,34* Average daily gain in live weight, g 53,95 ± 0,43 55,57 ± 0,41* Gross feed consumption, g / head 3406,89 ± 111,24 3490,14 ± 184,42 Average daily feed consumption, g 84,50 ± 2,76 90,32 ± 4,77 Feed conversion, g / g 1,600 ± 0,000 1,558 ± 0,000* * - the difference is significant compared to the control at p < 0.05%

[0077] The main productivity indicator, live weight, significantly increased by 2.95% during the rearing period in the experimental group compared to the control group. Furthermore, feed conversion significantly improved by 2.63% in the experimental group compared to the control group.

[0078] The gross gain in live weight significantly increased by 3.01%, the average daily gain by 3.00% in the experimental group compared to the control group.

[0079] The composition and nutritional value of the diet, as well as the introduction of feed additives, have a significant impact on energy, carbohydrate and mineral metabolism in the body of animals.

[0080] Blood biochemistry: In the experimental group, a significant increase in total protein and albumin, and a decrease in total cholesterol and LDL levels were observed. ALT, AST, and alkaline phosphatase enzyme activity in the blood of birds in the experimental group were significantly lower, indicating a reduced load on the liver and the antioxidant activity of the supplement.

[0081] Based on the results of scientific and industrial experiment on studying the effect of additives based on fungal biomass, the following conclusions were formulated:

[0082] 1. The preservation of bioactive components was confirmed indirectly through physiological parameters of the animals. A significant improvement in productivity indicators (live weight, average daily gain, feed conversion) indicates high bioavailability and functional preservation of the nutrients and bioactive substances in the mushroom biomass after processing.

[0083] 2. An increase in the level of total protein and albumin in the blood serum with a simultaneous decrease in the activity of ALT, AST, and alkaline phosphatase reflects an improvement in protein metabolism and a decrease in the metabolic load on the liver, which is typical for feed components with preserved native protein structure and antioxidant activity.

[0084] Including a mushroom biomass-based feed supplement in broiler chicken diets has a comprehensive positive effect on the bird's body. This is manifested in a significant increase in productivity and feed conversion, improved meat quality, optimization of metabolic processes, and a boosted immune system.