Isolation Of The Velum Microorganisms From The TengChong White Vinegar And Application To Brewing Mulberry Beverage

There is a long history of vinegar and wine being brew and edible in China, and both of them are still people's daily necessities all over the world. Microorganisms play an important role in the production process of vinegar and wine. Vinegar is made from the oxidation of ethanol by acetic acid bacteria, which also make the ethanol into some flavor substances through its metabolic processes; Wine is made from the fermentation of carbohydrate by yeast, which also provides some flavor substances during the process. TengChong white vinegar is a special local product in Yunnan province, which is fermented by using folk craft of wild fermentation. That is to say, the microorganisms involved in the fermentation are not artificially added but totally from the environment. During the production process of TengChong white vinegar, the biofilm formed on the surface of fermentation broth is looks like medusa. This phenomenon involves immobilization of several kinds of microorganisms. The microbes from the biofilm are isolated and identified via morphological, physiological and biochemical test, and they are get prepared for using in other ways.There is also a long history of sericulture in China, which is developed along with economic development, industrial structure adjustment and people's consumption level or consumption concept. Comprehensive exploitation and utilization of related resources is the trend of sericulture development, and the mulberry fruit is one of the most important resources. Mulberry fruit can be manufactured as mulberry fruit vinegar, mulberry fruit wine, mulberry fruit red pigment or any other deep processed production which using mulberry fruit as raw material. Brewing mulberry fruit vinegar usually contains two steps:first, alcoholic fermentation, and then, acetic acid fermentation. There is no reports about one-step fermentation, which means activated acetic acid bacteria is inoculated in mulberry fruit juice that already contains certain concentration of alcohol, and directly to ferment as fruit vinegar. The optimization of process conditions on one-step fermentation are demonstrated by both single factor test and orthogonal design test. The semifinished product of mulberry fruit vinegar is then clarified to get the non-turbid and non-precipitated transparent liquid. Mulberry fruit wine is fermented by yeast which is inoculated into the mulberry fruit juice that contains certain sugar degree. Both single factor test and orthogonal design test were carried out for detecting the optimal process conditions, and the mulberry fruit wine was also clarified.The results are as follows:1. There are two dominant microbes from the biofilm of TengChong white vinegar are isolated, which identified as acetic acid bacteria and yeast by morphological, physiological and biochemical tests.2. Both single factor test and orthogonal design test are carried out for detecting the optimal process conditions of one-step fermentation to brew the mulberry fruit vinegar. The results showed that the optimal conditions of one-step fermentation are 6% alcohol (V/V) in the incipient stage; 130 r/min of rotation speed; and the inoculum size of acetic acid bacteria is 15% (V/V). There are three single clarifiers including casein, diatomite and chitosan which used respectively to clarify the mulberry fruit vinegar are taking into comparison. The results indicated that chitosan is the best clarifier among the candidates, and the optimum concentration of chitosan is 1.6 mL/100mL. After clarification, the mulberry fruit vinegar is light rose pink, non-turbid and non-precipitated transparent liquid with complex flavor of vinegar and mulberry fruit.3. The results showed that the conditions of brewing mulberry fruit wine are 17% sugar degree in the incipient stage; inoculum size of yeast is 10%(V/V); and the optimum temperature is 21℃. There are four single clarifiers including casein, diatomite, gelatin, chitosan and a combined clarifier chitosan-gelatin are respectively used to clarify the mulberry fruit wine. The results indicated that the combined clarifier chitosan-gelatin is better than the other four single clarifiers. The optimum addition size is 2% gelatin solution 8mL/100mL and 1% chitosan solution 10mL/100 mL. After clarification, the mulberry wine is deep rose pink, non-turbid and non-precipitated transparent liquid with complex flavor of bouquet and mulberry fruit.