阅读说明：本技术 一种高含量酵母蛋白饲料的清洁生产方法 (Clean production method of high-content yeast protein feed ) 是由 符秀迪 程勐万里 孟龙 薛芹 于 2019-11-22 设计创作，主要内容包括：本发明涉及一种高含量酵母蛋白饲料的清洁生产方法,将大麦粉碎加水调浆酶解得带渣糖化液,固液分离得大麦蛋白湿渣和稀糖液；将一部分稀糖液经过加热蒸发浓缩后制得浓糖液,剩余稀糖液备用；将浓糖液中加入尿素和磷酸氢二钾,溶解后得营养液；将稀糖液稀释灭菌冷却后,接入酵母菌种子液,通入无菌空气进行培养,培养过程中流加营养液,当发酵液溶氧逐渐升高至60％以上时停止流加营养液和培养即得酵母发酵液,经离心分离得高浓度酵母浆；将高浓度酵母浆与大麦蛋白湿渣混合烘干得高含量酵母蛋白饲料。本发明的高含量酵母蛋白饲料,富含动物必须氨基酸、β～葡聚糖、促生长因子、膳食纤维等养分,具有促生长、易消化和增强动物免疫力等特点。(The invention relates to a clean production method of high-content yeast protein feed, which comprises the steps of crushing barley, adding water, pulping, performing enzymolysis to obtain saccharified liquid with dregs, and performing solid-liquid separation to obtain wet barley protein dregs and dilute sugar liquid; heating, evaporating and concentrating a part of the diluted sugar solution to prepare a concentrated sugar solution, and reserving the rest diluted sugar solution for later use; adding urea and dipotassium hydrogen phosphate into the concentrated sugar solution, and dissolving to obtain a nutrient solution; diluting, sterilizing and cooling the dilute sugar solution, inoculating a yeast seed solution, introducing sterile air for culturing, feeding a nutrient solution in a flowing manner in the culturing process, stopping feeding the nutrient solution and culturing when the dissolved oxygen of the fermentation broth gradually rises to more than 60 percent to obtain yeast fermentation broth, and performing centrifugal separation to obtain high-concentration yeast slurry; mixing the high-concentration yeast slurry and the barley protein wet residue, and drying to obtain the high-content yeast protein feed. The high-content yeast protein feed is rich in nutrients such as essential amino acids, beta-glucan, growth promoting factors, dietary fibers and the like for animals, and has the characteristics of promoting growth, being easy to digest, enhancing the immunity of the animals and the like.)

1. A clean production method of a high-content yeast protein feed is characterized by comprising the following steps:

①, preparing barley protein wet residue, dilute sugar solution, concentrated sugar solution and nutrient solution:

pulverizing fructus Hordei vulgaris, adding water, pulping, adding liquefying enzyme, and saccharifying enzyme for enzymolysis to obtain saccharified liquid with residue, and performing solid-liquid separation to obtain wet residue of barley protein and diluted sugar solution;

heating, evaporating and concentrating a part of the diluted sugar solution to prepare a concentrated sugar solution, and leaving the rest of the diluted sugar solution as fermentation base sugar;

adding urea and dipotassium hydrogen phosphate into the concentrated sugar solution, dissolving to obtain a nutrient solution, sterilizing the nutrient solution at high temperature, and cooling for later use;

② preparation of high-density yeast fermentation liquid

Diluting the dilute sugar solution with water, sterilizing at high temperature, cooling, inoculating yeast seed solution, introducing sufficient sterile air, culturing, adding nutrient solution in flow during the culture process, stopping adding nutrient solution when the dissolved oxygen in the fermentation broth gradually rises to above 60%, and stopping culturing to obtain yeast fermentation broth;

③ preparation of high concentration yeast slurry

Carrying out centrifugal separation on the yeast fermentation liquor to obtain high-concentration yeast slurry and fermentation supernatant;

④, preparation of high-content yeast protein feed:

mixing and drying the high-concentration yeast slurry and the barley protein wet residue to prepare high-content yeast protein feed;

or drying the high-concentration yeast slurry and the barley protein wet residue respectively, and mixing to prepare the high-content yeast protein feed;

or drying the barley protein wet residue, mixing with high-concentration yeast slurry, and drying to obtain the high-content yeast protein feed.

2. The clean production method of high-content yeast protein feed as claimed in claim 1, characterized in that: the yeast seed liquid is Saccharomyces cerevisiae CICC 32280.

3. The clean production method of a high-content yeast protein feed as claimed in claim 1, wherein the dry matter concentration of the concentrated sugar solution in the step ① is 30-60%, and the mass ratio of urea, dipotassium hydrogen phosphate and the concentrated sugar solution in the nutrient solution is 0.001-0.04: 0.001-0.006: 1.

4. The clean production method of a feed with high yeast protein content as claimed in claim 3, wherein the dry matter concentration of the concentrated sugar solution in step ① is 40-50%, and the mass ratio of urea, dipotassium hydrogen phosphate and concentrated sugar solution in the nutrient solution is 0.01-0.04: 0.003-0.006: 1.

5. The clean production method of the feed with high yeast protein content according to claim 1, wherein the nutrient solution in step ① is sterilized at high temperature and then cooled to 80-100 ℃ for 15-30 min, and then cooled to 30-40 ℃.

6. The clean production method of high-content yeast protein feed according to claim 1, characterized in that the specific production conditions of the high-density yeast fermentation liquid in step ② are as follows:

diluting the dilute sugar solution to a concentration of 0.01-5%; the inoculation mass ratio of the yeast seed liquid is 0.2-20%;

the sterilization and cooling conditions of the nutrient solution are as follows: sterilizing at the high temperature of 80-120 ℃ for 1-30 min, and cooling to 20-40 ℃;

when preparing the yeast fermentation liquor: fermentation temperature: 20-40 ℃; fermentation pH: 4.0 to 6.0; the stirring speed of aerobic fermentation is 20-1000 r/min; the ventilation ratio is 1: 0.5-3 v/v; the concentration of dissolved oxygen is 10-100%; and (3) fermentation period: 12-96 h, the number of bacteria at the end point of yeast fermentation is 0.5-1.0 multiplied by 10⁹cfu/ml。

7. The clean production method of high-content yeast protein feed according to claim 6, characterized in that the specific production conditions of the high-density yeast fermentation liquid in step ② are as follows:

diluting the dilute sugar solution to a concentration of 0.5-2%; the inoculation mass ratio of the yeast seed liquid is 5-10%;

the sterilization and cooling conditions of the nutrient solution are as follows: sterilizing at the high temperature of 80-90 ℃ for 20-30 min, and cooling to 30-35 ℃;

when preparing the yeast fermentation liquor: fermentation temperature: 30-35 ℃; fermentation pH: 4.0 to 5.0; the rotation speed of aerobic fermentation stirring is 100-150 r/min; the ventilation ratio is 1: 1-2 v/v; the concentration of dissolved oxygen is 30-60%; and (3) fermentation period: 72-80 h, the number of bacteria at the end point of yeast fermentation is 0.8-1.0 multiplied by 10⁹cfu/ml。

8. The clean production method of high-content yeast protein feed as claimed in claim 1, wherein the preparation conditions of the high-content yeast protein feed in step ④ are as follows:

the mass ratio of the high-concentration yeast slurry to the barley protein wet residue is 100: 50 to 100.

9. The clean production method of high-content yeast protein feed according to claim 8, wherein the preparation conditions of the high-content yeast protein feed in step ④ are as follows:

the mass ratio of the high-concentration yeast slurry to the barley protein wet residue is 100: 65-70.

10. The clean production method of the feed with high yeast protein content as claimed in claim 1, wherein in the step ①, a part of the dilute sugar solution accounts for 95-99% of the dilute sugar solution by mass.

Technical Field

The invention belongs to the fields of microbial fermentation technology and feed, and particularly relates to a clean production method of high-content yeast protein feed.

Background

China is a big population country and also the first pig-raising country in the world. In 2017, the livestock production value in China reaches 3.6 trillion yuan, live pigs are slaughtered 6.89 trillion heads, wherein the number of the stocked sows is 4200 trillion heads, and the pork yield is 5967 trillion tons. According to the statistical data of Ministry of agriculture, the national commercial feed yield in 2017 reaches 2.05 hundred million tons. Wherein, the complete feed is 1.79 million tons, the concentrated feed is 2151 million tons, the premix compound is 690 million tons, and comprises 8974 million tons of pig feed output, 9000 million tons of poultry feed output, 5300 million tons of aquatic feed, 850 million tons of cattle and sheep feed, 350 million tons of feed such as rabbit, racoon dog and pet animals, and 500 more than ten million tons of feed for the national sow. The national compound feed yield is expected to reach more than 2.2 hundred million tons in 2020, wherein the feed for sows reaches more than 800 ten thousand tons. The animal protein feed is relatively deficient in resources, and the content of essential amino acid in the vegetable protein is relatively low. With the development of animal husbandry production, the protein demand of animals is larger, while the total amount of agricultural production is limited, and the protein feed required for growth is larger. The saccharomyces cerevisiae mycoprotein has high nutritive value, the protein content in the yeast dry matter can reach 50 percent, the essential amino acid content required by animals is high, the content is close to animal protein, and the utilization rate of the net protein is far higher than that of plant protein. In addition, the saccharomyces cerevisiae also contains abundant nucleotide, B vitamins, minerals and other physiological active substances. With the development of microbial engineering and fermentation engineering, saccharomyces cerevisiae is more and more widely used for producing high-quality protein feed.

Meanwhile, with the wide application of yeast in feed, the realization of high-density fermentation of yeast in a fermentation tank space with limited volume is a key for maintaining the production scale of yeast products and controlling the cost, so that research on various characteristics of yeast, particularly fermentation characteristics, is necessary.

According to the traditional yeast value-added fermentation method, high-density fermentation of saccharomyces cerevisiae is realized by optimizing culture conditions, and a set of complete fermentation process is formed by integrating and optimizing a plurality of factors and mutual influences thereof, wherein the process is a work with complex program and high comprehensiveness. In addition, the yeast extraction production cost is high, and the discharge amount of the production wastewater is large. Therefore, according to the mode of carbon source utilization of saccharomyces cerevisiae, the yeast feed production process which is suitable for large-scale industrial production and is energy-saving and environment-friendly is required to be developed by adopting the nutritional ingredients with wide raw material sources and low price.

Disclosure of Invention

The invention aims to solve the problems of animal protein resource shortage, high yeast production cost and large wastewater discharge amount, and provides a clean production method of high-content yeast protein feed.

The technical scheme adopted by the invention is as follows:

a clean production method of high-content yeast protein feed comprises the following steps:

①, preparing barley protein wet residue, dilute sugar solution, concentrated sugar solution and nutrient solution:

pulverizing fructus Hordei vulgaris, adding water, pulping, adding liquefying enzyme, and saccharifying enzyme for enzymolysis to obtain saccharified liquid with residue, and performing solid-liquid separation to obtain wet residue of barley protein and diluted sugar solution;

heating, evaporating and concentrating a part of the diluted sugar solution to prepare a concentrated sugar solution, and leaving the rest of the diluted sugar solution as fermentation base sugar;

adding urea and dipotassium hydrogen phosphate into the concentrated sugar solution, dissolving to obtain a nutrient solution, sterilizing the nutrient solution at high temperature, and cooling for later use;

② preparation of high-density yeast fermentation liquid

Diluting the dilute sugar solution with water, sterilizing at high temperature, cooling, inoculating yeast seed solution, introducing sufficient sterile air, culturing, adding nutrient solution in flow during the culture process, stopping adding nutrient solution when the dissolved oxygen in the fermentation broth gradually rises to above 60%, and stopping culturing to obtain yeast fermentation broth;

③ preparation of high concentration yeast slurry

Carrying out centrifugal separation on the yeast fermentation liquor to obtain high-concentration yeast slurry and fermentation supernatant;

④, preparation of high-content yeast protein feed:

mixing and drying the high-concentration yeast slurry and the barley protein wet residue to prepare high-content yeast protein feed;

or drying the high-concentration yeast slurry and the barley protein wet residue respectively, and mixing to prepare the high-content yeast protein feed;

or drying the barley protein wet residue, mixing with high-concentration yeast slurry, and drying to obtain the high-content yeast protein feed.

Further, the yeast seed liquid is saccharomyces cerevisiae CICC 32280.

Furthermore, in the step ①, the dry matter concentration of the concentrated sugar solution is 30-60%, and the mass ratio of urea, dipotassium hydrogen phosphate and the concentrated sugar solution in the nutrient solution is 0.001-0.04: 0.001-0.006: 1.

Preferably, the dry matter concentration of the concentrated sugar solution in the step ① is 40-50%, and the mass ratio of urea, dipotassium hydrogen phosphate and concentrated sugar solution in the nutrient solution is 0.01-0.04: 0.003-0.006: 1.

Further, the temperature of the nutrient solution is reduced after high-temperature sterilization in the step ①, wherein the nutrient solution is sterilized at the high temperature of 80-100 ℃ for 15-30 min and then is cooled to 30-40 ℃.

Further, the specific conditions for producing the high density yeast fermentation broth in step ② are as follows:

diluting the dilute sugar solution to a concentration of 0.01-5%; the inoculation mass ratio of the yeast seed liquid is 0.2-20%;

the sterilization and cooling conditions of the nutrient solution are as follows: sterilizing at the high temperature of 80-120 ℃ for 1-30 min, and cooling to 20-40 ℃;

when preparing the yeast fermentation liquor: fermentation temperature: 20-40 ℃; fermentation pH: 4.0 to 6.0; the stirring speed of aerobic fermentation is 20-1000 r/min; aeration ratio1: 0.5-3 v/v; the concentration of dissolved oxygen is 10-100%; and (3) fermentation period: 12-96 h, the number of bacteria at the end point of yeast fermentation is 0.5-1.0 multiplied by 10⁹cfu/ml。

Preferably, the specific production conditions of the high density yeast fermentation broth in step ② are as follows:

diluting the dilute sugar solution to a concentration of 0.5-2%; the inoculation mass ratio of the yeast seed liquid is 5-10%;

the sterilization and cooling conditions of the nutrient solution are as follows: sterilizing at the high temperature of 80-90 ℃ for 20-30 min, and cooling to 30-35 ℃;

when preparing the yeast fermentation liquor: fermentation temperature: 30-35 ℃; fermentation pH: 4.0 to 5.0; the rotation speed of aerobic fermentation stirring is 100-150 r/min; the ventilation ratio is 1: 1-2 v/v; the concentration of dissolved oxygen is 30-60%; and (3) fermentation period: 72-80 h, the number of bacteria at the end point of yeast fermentation is 0.8-1.0 multiplied by 10⁹cfu/ml。

Further, the preparation conditions of the high content yeast protein feed in step ④ are as follows:

the mass ratio of the high-concentration yeast slurry to the barley protein wet residue is 100: 50 to 100.

Preferably, the conditions for preparing the high yeast protein feed in step ④ are as follows:

the mass ratio of the high-concentration yeast slurry to the barley protein wet residue is 100: 65-70.

Further, in the step ①, a part of the dilute sugar solution accounts for 95-99% of the dilute sugar solution by mass.

The invention has the beneficial effects that:

(1) the invention adopts cheap raw materials, the obtained concentrated sugar solution is compounded with urea and dipotassium hydrogen phosphate to prepare nutrient solution, all nutrients required by yeast growth can be met by feeding the nutrient solution, the operation is simple, and the cost is low.

(2) The high-concentration yeast liquid prepared by the fermentation liquor through centrifugation can be completely matched with the produced barley residue, the mixed material has low viscosity and is easy to dry, the high-content yeast protein feed can be prepared only by directly drying through a low-energy-consumption tube bundle dryer, the centrifuged clear liquid can be recycled for barley flour size mixing, no waste water is produced, and the effects of energy conservation and environmental protection are achieved.

(3) The prepared high-content yeast protein feed has the yeast content of over 55 percent, is rich in nutrients such as essential amino acids, beta-glucan, growth promoting factors, dietary fibers and the like for animals, and has the characteristics of promoting growth, being easy to digest, enhancing the immunity of the animals and the like.

Detailed Description