Study On The Production Of Glucan And Mannose Oligosaccharides Of Waste Yeast

The generation of waste yeasts has been increasing in the development of the scale of yeast production because of the multifunction and widespread use.Waste yeast,as a by-product of yeast scale production,still contains large amounts of protein and vitamins.Most of the current methods for the disposal of waste yeast are using it as feed additives,or even discharging it directly.Not only it caused the waste of yeast utilization and added value is very low,but also polluted the environment.It is a significant research direction for waste yeast that how to turn the waste into wealth,promote the recycling of resources effectively,reduce environmental pollution and improve economic efficiency.Cell wall polysaccharide,which is an important component of waste yeast,plays a important role in feed,medicine and other fields.Related production development and utilization becomes the current hot spots.The technology of extracting polysaccharides from the waste yeast was developed through alkaline hydrolysis,enzymatic hydrolysis and other related techniques.The main research contents and conclusions are as follows:(1)It went through the 5 factor 4 level orthogonal experiment,and obtained its main processing technology: that is,after the pretreatment of100 g waste dried yeast powder by adding 250 ml of pure water,after enzymatic hydrolysis,washing and centrifugation,the heavy phase was added by 300 ml of sodium hydroxide solution(lye)for alkaline hydrolysis.The optimum conditions were as follows: papain;enzyme concentrationwas 2.25 ‰;the enzymolysis time was 6h;the alkali temperature was 45degrees;the alkaline hydrolysis time was 5.5h;the concentration of the caustic substance was 0.5mol / L.(2)The amplification of 100 times the parallel pilot scale test by three times(pretreatment waste dry yeast 10kg),the yield of the product was as follows: the average yield of dextran(yield): 8.18%,the average content of dextran: 72.08%,the average yield of mannose oligosaccharide(yield):2.14%,the average content of mannose oligosaccharides: 40.96%.(3)The results of data and laboratory scale test were basically consistent.It verified the program feasible and stable.(4)Determine the waste yeast co-production dextran,mannose oligosaccharide process plan: discarded the yeast pretreatment,after enzymatic hydrolysis,centrifugal removal of cell contents,and then by alkaline solution,after washing separation of heavy and light phase.Preparation of dextran by heavy phase and preparation of mannan oligosaccharide by light phase to realize co-production process.(5)Through the production of equipment,raw materials and other research,the finished product of the physical and chemical indicators were clear,the economic indicators were estimated that the annual production of dextran is expected to 14 tons,4 tons of mercuric oligosaccharides,Of which equipment invested 727,800 yuan,the other cost of 3.6 million yuan investment,is expected to annual sales of 6.92 million yuan,annual gross profit of 2.6 million yuan.