Study On Lactobacillus Plantarum HQ-3 Fermented Purple Potato Beverage

In this experiment,with the purple potato as raw material,Lactobacillus plantarum HQ-3,which has good fermentation effect,strong acid and bile salt resistance,strong adhesion and potential prebiotic function,was selected as the fermentation strain.Through the selection and optimization of the technological conditions of purple potato liquefaction,saccharification,fermentation and stabilizer addition,a pure purple horse was developed Lactic acid bacteria fermented beverage of sweet potato.The main organic acids were determined.The results are as follows:(1)The optimum conditions of purple potato liquefaction were determined by single factor experiment and response surface experiment: adding 13.5 U/100 ml enzyme,hydrolysis time of 52 min,initial pH value of 6.0 and temperature of 60 ?;adding 60 U /100 ml enzyme,hydrolysis time of 90 min,initial pH value of 4.0 and temperature of 60 The content of reducing sugar was(45.23 ± 0.12)%.(2)The best process for preparing purple potato fermented beverages was determined:Under the conditions of 4% Lactobacillus plantarum,38 ? fermentation temperature,25 h fermentation time and 4 initial pH,the sensory evaluation score of purple potato was(85.23 ± 0.89),the acidity was(83.8 ± 0.36)°T,the number of viable bacteria was(9.38 ±0.21)log(CFU / ml)and the anthocyanin content was(51.43 ± 0.41)mg/L.(3)The optimum formula of stabilizer was determined: 0.06% sodium carboxymethylcellulose,0.08% pectin,0.04% xanthan gum.The centrifugal precipitation rate was(3.95 ± 0.49)%.(4)Using HPLC to detect the composition of purple potato beverage for preliminary analysis,the results showed that oxalic acid increased by 39%,acetic acid increased by62%,and lactic acid appeared after fermentation.The content of lactic acid was 7664.7 ?g/ ml.(5)The purple potato beverage products were stored at 4 ?.The results showed that the number of viable bacteria decreased from(9.32 ± 0.36)log(CFU / ml)to(7.16 ± 0.21)log(CFU / ml),the acidity increased from(78.9 ± 0.6)°T to(95.3 ± 0.4)°T,and the centrifugal precipitation rate increased from(3.96 ± 0.35)% to(6.69 ± 0.26)%.