Study On The Technology And Quality Of Quinoa Yoghurt

Quinoa is rich in nutrition,strong in health care and high in economic value.In recent years,with the rapid development and in-depth research of the miscellaneous grain industry,its "green,natural,nutritional,health care" and other characteristics are well known by consumers.Yogurt as a convenient and easy-to-eat food meets the needs of consumers under the modern fast pace,and the market development prospect is very broad.In this study,quinoa was used as the main raw material,and quinoa yogurt was developed through the main processes of soaking,steaming,refining,filtering,and fermentation.Through single factor experiment,orthogonal experiment and other methods to determine the best production process and production formula of quinoa yoghurt,further study the quality of yoghurt and the dynamic changes of quality during storage,the main research results are as follows:1.Selection of raw materials for quinoa yoghurt and optimization of pretreatment process.(1)Select Jingle quinoa as the preferred raw material for this experiment,its amino acid content is 12.43 g / 100 g,and it is added by refining;the material-water ratio of quinoa pulp prepared is 1: 5,refining temperature is 60 ?,The refining time is 3 min,and the filtration parameter is 100 mesh.At this time,the quinoa syrup was slightly yellow,and the grain aroma was strong.Quinoa pulp protein content is 0.153 g / 100 g,fat content is 0.1 g / 100 g,amino acid content is 0.097 g / 100 g,and flavonoid content is 7.4x10-5 mg / ml.There are 59 volatile components in quinoa pulp,among which the highest content is esters.2.Research on quinoa yogurt process optimization and stability.The final fermentation time was 7 h,the fermentation temperature was 40 ?,the addition of white sugar was 8%,the addition of quinoa pulp was 20%,and the inoculum of bacterial powder was 0.3%.Under this optimal condition,the acidity of quinoa yogurt was 84.7 ° T,and the sensory score was 89.5.The best compounding formula of quinoa yoghurt is carrageenan 0.05%,gelatin 0.07%,xanthan gum 0.01%.3.Quality analysis of quinoa yogurt.(1)The color of quinoa yogurt is milky white,with a strong quinoa aroma,even and harmonious;the taste is delicate and smooth,the sweet and sour is moderate;the product texture is uniform without precipitation.(2)The protein content of quinoa yogurt is 3.18 g / 100g;the fat content is 1.13 g / 100g;the flavonoid content is 1.45x10-5g / 100 g.The amino acid content is 3.17 g / 100g;the total number of lactic acid bacteria is 3.27 × 106 cfu / ml.(3)There are 35 volatile components in quinoa yoghurt.Esters,acids,and heterocyclic compounds are the main flavoring substances in quinoa yoghurt.Among them,the most important contribution to quinoa yogurt is ester compounds.(4)The number of molds in quinoa yogurt is <10 CFU / mL,and E.coli is <60 MPN / L.The microbiological indicators are in compliance with national standards.(5)The protein content of quinoa yogurt is 0.294 g / 100 g higher than the average level;the fat content is only half of the other samples tested;the content of essential amino acids is also significantly higher than that of the tested yogurt.(6)The flavor substance of quinoa yoghurt is significantly higher than that of the other four commercially available yoghurts,and the content of dioctyl adipate is as high as 71.71%.Methyl eicosapentaenoate,dioctyl adipate,diisooctyl phthalate,dibutyl phthalate 1,6-caprolactam,cetyl were also detected in quinoa yogurt Volatile components such as dimethyl tertiary amine give quinoa yogurt a unique flavor.4.The dynamic change of quinoa yogurt during storage.Molds and yeasts tend to be stable under cold storage conditions,no obvious changes,and slightly increase at room temperature.Under both conditions,the number of lactic acid bacteria gradually decreased.Under cold storage conditions,the total number of lactic acid bacteria was lower than the national standard on the 15 th day,and lower than the national standard on the 5th day at room temperature.Therefore,it is recommended that this yogurt be consumed within 5 days at room temperature and within 15 days under refrigeration.In summary,the quinoa yoghurt developed in this study has a delicate taste and suitable flavor,and has certain nutritional and health care value.This research not only enriches the types of processed cereal products,but also improves the processing technology level of cereals,and to a certain extent is conducive to promoting the healthy and rapid development of China's cereals industry.