Development Of Pueraria Walnut Peptide Compound Beverage

Kudzu vine root is a kind of wild plant resource using as both medicine and food, walnut oil production produces a lot of walnut cakes. This paper focused on kudzu vine root and walnut cake to optimize the technological conditions on fermenting by lactic acid bacteria and obtaining peptide, the research on preparation of compound beverage with its taste and stability and processing into solid beverage, the main results were as follows:1. The best fermentation process based on flavonoids extraction yield and sensory evaluation was studied by orthogonal experiment, the results were that the raw material ratio of walnut cake and puerarin was 1:3, the sucrose was 1%, ratio of solid to liquid was 1:15, Lactobacillus(1:1 mixture of L.bulgaricus and Lactococcus lactis) inoculation amount was 4% and 2 d fermentation at 39?, the flavonoids extraction yield was up to 3.812mg/g and sensory score was 92 at the optimum condition.2. Comprehensive peptide yield and sensory evaluation of hydrolyzate, Neutral protease was chosen as the optimum enzyme. The optimum conditions which used Neutral protease were determined by response surface methodology:enzyme amount 5000u/g, substrate concentration 23g/L, temperature 51?, time 5.2h, p H natural, under the optimum conditions, peptide yield was 0.45g/g; Molecular weight distribution of walnut power flour was extensive with the range of 18 k Da~37k Da, and molecular weight distribution of peptide was bellow 7.6k Da.3. Comprehensive sensory evaluation and the requirement between protein concentration and peptide content of protein beverage on the market, the addition level of 6% peptide in compound beverage of puerarin and walnut peptide was determined; The optimum conditions based on sensory evaluation, which used sweet adjustment were determined by orthogonal experiment: white sugar 8%, citric acid 0.1% and walnut flavor 0.08%; The optimum conditions based on sensory evaluation, which used stability were determined by response surface methodology: xanthan gum 0.11%, sodium carboxymethyl cel ulose 0.10%, propylene glycol alginate(PGA) 0.17%, sucrose ester 0.14%.4. Comprehensive moisture content, hydrophilic, drying process and sensory evaluation of solid beverage, maltodextrin was chosened as the main drying aids and ?-cyclodextrin played a supporting role; The optimum conditions based on moisture content and sensory evaluation, which used spray drying were determined by orthogonal experiment: material concentration 15%, inlet air temperature 170?, feed flow rate 1.96ml/min, maltodextrin rate 80%, beta cyclodextrin 10%; under the optimum conditions, moisture content was 3.98%, sensory evaluation was 95.