Research On Fermentation Technology Of Purple Sweet Potato Vinegar

The paper mainly studied the development of purple sweet potato vinegar, which tookpurple sweet potato as the raw material, carried on alcoholic fermentation and acetic acidfermentation after double enzyme hydrolysis, and got a product which had high nutritional valueand bright color. The starch hydrolysis process parameters of purple potato was determined afterhydrolyzing using enzyme preparation; Using the hydrolyzate of purple sweet potato as the rawmaterial, the author got the process conditions of alcohol fermentation and acetic acidfermentation; Finally the purple potato vinegar clarification conditions were determined. Thetest results are as follows:1、Purple potatoes are rich in starch. This experiment studied the effect of liquefaction ofalpha amylase, the process parameters of liquefaction were obtained: the addition of α-amylasewas0.25%(of purple sweet potato)、liquefied temperature of65℃, hydrolysis time2.0h, pH5.5.The starch of purple potato were liquefied more completely.2、Using the glucoamylase to saccharify the purple potato which was liquefied, the contentof reducing sugar was an index. On the basis of single factor experiment, the saccharificationparameters of the purple potato was determined using the method of orthogonal experiment: theaddition of glucoamylase was0.25%(of purple sweet potato)、liquefied temperature of60℃,hydrolysis time2.5h, pH4.5.3、This experiment studied the alcoholic fermentation of the purple potato which wassaccharified, using Dan polly wine highly active dry yeast. The degree of alcohol was an index.On the basis of factor experiment which included the amount of yeast, fermentation temperature,pH, the process parameters of the alcoholic fermentation was determined by the method oforthogonal experiment: the dosage of yeast was1.0‰, initial pH5.0,the fermentationtemperature was28℃.4、The experiment selected the addition of acetic acid bacteria, fermentation temperature,initial degree of alcohol, the value of pH as single factors. On the basis of single factorexperiment, the process parameters of the acetic acid fermentation was determined by themethod of orthogonal experiment: the addition of acetic acid bacteria was8%, the initial degreeof alcohol was8%, pH5.0, the fermentation temperature was34℃. In this condition,we can getthe purple sweet potato vinegar which concentration is5.27g/100mL.5、The experiments of clarifications were conducted using a gelatin, diatomite, chitosan onpurple sweet potato vinegar. We can see that the best method of clarification on purple sweet potato vinegar was chitosan by comparing the transmittance of different methods ofclarifications. The addition of chitosan was0.2g/L.