Study On The Technology Of Yam Skin Vinegar And Its Beverage

Yam skin is a yam series of waste products,the yam utilization rate is very high,and have rich variety of processed products.But yam skin reuse has not been paid attention,only a small amount as a feed to add.Yam skin composition and yam is roughly the same,have tonifying spleen and stomach,profiting lung and other effects,it can be used for spleen deficiency food,lung cough cough,and the resource is very rich,the price is low,the development and utilization of potential extremely great.Explore the development of yam vinegar and beverage have dual economic and environmental benefits.In this study,first the optimum conditions and the content of active components in the yam skin were determined,then alcohol fermentation and acetic acid fermentation of yam skin,further explore clarification method,eventually make yam skin product vinegar,on the basis of yam peel vinegar beverage drink of new product development.The results of the study are as follows:(1)Through the extraction conditions and content of active components in yam skin were analyzed,we can see:(1)the yam skin of polysaccharide in solid-liquid ratio is 1:15,extraction temperature is 70 ?,extracting time for 3 h experimental conditions to get the highest content of crude polysaccharide,treated with standard curve method of yam skin coarse polysaccharide,under the condition of the extraction experiment,the skins of yam polysaccharide extraction rate reached 6.51%.(2)The content of flavonoids in the yam skin was the highest at the ratio of 1:20,the extraction temperature was 60 ?,the extraction time was 2h and the ethanol volume fraction was 70%.The content of flavonoids was the highest The regression equation of the curve shows that the extraction rate of flavonoids in the mountain skin is 1.15%.(2)The reducing sugar content of yam skin is 2.15%.Because of yam skin contains a certain amount of starch material,this study focused on starch material is decomposed into a reducing sugar,for the next step of alcoholic fermentation with carbon source and energy.This experiment by using the principle of amylase digestion of starch into glucose,explore the alpha amylase liquefied effect of yam skin powder.First of all,the influencing factors were tested at the appropriate level of single factor test,and then the orthogonal test was used to optimize the single factor test results,we can know : in(yam skin powder)and solid-liquid(distilled water)ratio of 1:2,the liquefaction temperature is 65 ?,the total for the amount of alpha amylase yam skin liquid ratio is 0.15%,liquefaction time for 2.5h,solution pH value of 6 under the conditions ofstarch liquefaction process,the solution can reach 4.98%,reducing sugar content in the skins of yam starch can be completely liquefied.(3)On the basis of yam skin after liquefaction,Saccharifying enzyme was used to treat the skin of yam and the content of reducing sugar in yam skin was taken as index,we can get the optimal saccharification parameters : the temperature is 65?,the amount of glucoamylase is 0.1%,the saccharification time is 2h and the pH value is 4.5.Under this condition,the content of reducing sugar is9.64%,it could provides the sufficient carbon source for the alcohol fermentation and acetic fermentation.(4)The alcoholic fermentation of yam pulp was carried out by three kinds of yeasts such as Saflager S-23 beer brewing Lager dry yeast,Angela wine yeast and Dan polly wine highly active dry yeast,the alcoholic degree was selected as the index,Dry yeast Saflager S-23 is the best yeast.Select the amount of yeast,fermentation temperature,pH value to do single factor test,orthogonal optimization test based on single factor test,the optimum process parameters of ethanol fermentation were determined: fermentation temperature 32?,the amount of yeast 1.2g/L,pH 4.0,under this condition,the alcohol reached 7.5degrees.(5)Choose acetic acid bacteria inoculation quantity,fermentation temperature,p H value for single factor experiment.After obtaining the three factors of the appropriate level of acetic acid fermentation,we can get the optimum parameters of acetic acid fermentation is: temperature30?,inoculation amount 10%,initial pH value5.0.(6)Select diatomaceous earth,bentonite,pectinase to clarify the yam peel vinegar,by comparing the size of the light transmittance,we know the diatomite is the best to clarify the vinegar vinegar.Adding amount of components are 0.4%,get brown clarify yam peel vinegar product.(7)In order to further enrich vinegar beverage products market types,on the basis of yam peel vinegar,add sugar and citric acid.First of all,the scope of the three factors were studied,then the orthogonal optimization test was used to determine the amount of each factor: yam peel vinegar12%? sugar 9% ?citric acid 0.15%.