Optimization Of Production Process Of Brewer’s Yeast Hydrolysate And Its Application In Pig Production

Beer yeast cells contain various amino acids,peptides,sugars,nucleic acids,enzymes and coenzyme factors,which are rich in nutrients and have high utilization value.With the rapid development of the beer industry,the production of beer waste yeast sludge is also increasing.Saccharomyces cerevisiae is rich in nutrients and can be processed by modern high-tech biotechnology to produce yeast and its derivatives suitable for various fields such as food,fermentation and animal feed.Beer yeast hydrolysate is rich in protein,sugar,nucleic acid,vitamins,minerals,lipids and other nutrients.Its nutritional value is equivalent to fishmeal.It is an excellent substitute for protein feed.It is sustainable and green for China’s feed industry.The development is of beer yeast hydrolysate is great significance.This thesis focuses on the brewer’s yeast mud produced in the beer brewing process.It summarizes the development process,nutritional value and utilization methods of brewer’s yeast,and the various physical and chemical methods for cell disruption,such as physical,chemical and biological methods,and their advantages and disadvantages.In this paper,the cell wall breaking conditions of yeast cells were studied.The effects of different temperature,substrate concentration,pH and time on the cell wall disruption were investigated.The optimal breaking conditions of yeast cells were obtained.The temperature was 50 ° C,the substrate concentration was 10%,the pH was 6.0,and the action time was 30 h.In this paper,the effects of papain,trypsin and neutral protease on the hydrolysis of yeast cells under different time,concentration and pH conditions were studied,and the enzymatic conditions of yeast hydrolysate were optimized.The results showed that the optimal conditions for papain were: 0.50%(w/v)protease,pH 7.00,hydrolysis time 30 h;optimal conditions for trypsin were: 0.30%(w/v)protease,pH 6.0,hydrolysis time 40 h;the optimal process conditions for neutral protease are: 0.30%(w/v)protease,pH 6.00,hydrolysis time 40 h.Considering enzymatic hydrolysis and traditional broken wall process conditions,when papain was added,the enzyme amount was 0.50%(w/v),the pH was 7.00,and the hydrolysis time was 30 h.The effects of adding beer yeast hydrolysate on the growth performance,antioxidant index and immune index of piglets were studied,which provided scientific basis and reference for its application in piglets.The results showed that adding 10 kg/t of brewer’s yeast hydrolysate to the diet of weaned pigs significantly reduced the feed-to-weight ratio,which was 5.40%(P < 0.05),and effectively improved the growth performance of piglets;adding brewer’s yeast hydrolysate to piglet serum The antioxidant activity of glutathione peroxidase,total antioxidant capacity and superoxide dismutase had no significant effect;the addition of brewer’s yeast hydrolysate in the diet could significantly increase the content of immunoglobulin IgG in the serum of piglets.