Study On The Preparation Of Fermented Dairy Products By Concentrated Whey Protein

Whey is a by-product produced in cheese production,which has high nutritional value.Whey is rich in lactose,crude fat and crude protein,which can pollute the environment.Microorganisms in the environment will also use whey to pollute the environment.Therefore,untreated whey cannot be directly discharged into the environment.Whey contains more than half the solids found in full-fat milk,including whey protein,most lactose,vitamins and minerals.Whey protein not only has high nutritional value,but also contains amino acids needed by human body,which can be used as a high-quality protein supplement.Therefore,the development of whey protein fermented milk,both from the nutritional value and environmental aspects,is of great significance.In this paper,a new type of fermented dairy products was developed by lactic acid bacteria fermentation using concentrated whey protein-34 powder as the main raw material.In order to improve the quality of condensed whey protein fermented milk,response surface methodology(RSM)was used to optimize the production process,select and combine the stabilizers of condensed whey protein fermented milk,and study some physicochemical properties during storage.The experimental results are as follows:1.Process optimization of whey protein concentrate fermented milk.Using single factor experiment,with concentration of the pH value of the fermented milk whey protein,acidity,the hydraulic,quality and structure and sensory evaluation as the index,the factors that determine the best range of select Box-Behnken experiment design,with sensory score as response value,through the response surface method for fermented milk whey protein concentrate,process optimization,it is concluded that the best process conditions:The addition amount of white granulated sugar was 6.08%,the addition amount of butter was 3.6%,the addition amount of starter culture was 0.2%,the fermentation time was 8.33 h.In order to verify the reliability of the combination,the optimal experiment was used to repeat the experiment for three times,and the sensory score of fermented milk was 88.78.The fermentation lactic acid under this process is sweet,delicate and unique.2.Study on milk stabilizer for concentrated whey protein fermentation.Through the influence of the four single stabilizers of low ester pectin,sodium alginate,acetylated disstarch phosphate,acetylated disstarch hexadiate on the viscosity value of fermented milk,the optimal adding amount range was screened out,and orthogonal test was conducted to obtain the optimal combination,that is,the adding amount of low ester pectin was 0.2%,and the adding amount of sodium alginate was 0.2%.The amount of acetylated disstarch phosphate ester was 0.2%,and the amount of acetylated disstarch adipic ester was 0.1%.3.Changes of whey protein concentrate fermented milk during storage.Under a certain storage days,based on the different storage temperature of fermented milk,and fermented milk whey protein concentrate and ordinary pH,acidity of fermented milk,hold water,such as the physical and chemical properties are measured,obtained under different storage conditions,the pH value is declining,but under 4? storage of fermented milk pH falling slowly,may be because of low temperature inhibiting the fermentation of lactic acid bacteria;The acidity value increases continuously under different storage conditions,which may be caused by the acidification after fermented milk.The change of water retention under different storage conditions is not obvious.Compared with common fermented milk,the quality of concentrated whey protein fermented milk in terms of pH,water holding capacity and texture is better than that of common fermented milk.