The Study Of Debittering Technology In Fermentative Prumus Mume Sieb.et Zucc Wine

As one of China’s traditional specialty, Prumus mume Sieb.et Zucc has four thousand years of cultural history in the domestic. In recent years, because of its rich nutrition, unique health function, the plum wine has become one of consumption wine in the domestic and international market, and become more and more popular among people, especially in the colour, taste and aroma. However, the Prumus mume Sieb.et Zucc fruit contains a large number of bitterness substances-amygdalin, the fermentation plum wine often has unacceptable bitterness lingering. Therefore, in the process of plum wine producting, debitterizing technology in plum wine is the key problems should be solved to improve brewing process, so as to remove the bad bitter or peculiar smell, and ameliorate flavor and taste in plum wine.Based on common methods to take off the bitter method in the fruit juice and fruit wine, this study choosed two technologies, the enzymatic (amygdalase) and adding bitterness inhibitors (P-cyclodextrin), to study on the fermentation plum wine, through designing the single factor experiment and the orthogonal experiment to obtain the best debitterizing conditions, and then evaluated synthetically from two aspects, aroma compositions change and human body sensory evaluation, the results were as follows:(1) By using the UV spectrophotometry to detect the change of amygdalin in plum wine before and after debitterizing. The best debitterizing technology and its optimum parameters in fermentation plum wine are:when using the amygdalase to debitterizing, the enzyme concentration was0.025u/mL, temperature was40℃, pH was5.2, the amygdalin debitterizing rate could amount to46.62%; when using the β-cyclodextrin to debitterizing, the P-cyclodextrin content was1.0%, temperature was45℃, time was30min, its debitterizing rate was45.71%.(2) By using the gas chromatography-mass spectrometry, we analysed the change of composition of fragrance in plum wine before and after debitterizing. It was concluded that aroma composition of plum wine mainly including alcohols, aldehydes, ketone and carboxylic acid kind in enzymatic, β-cyclodextrin suppression method and the control group. There are six common aroma compositions in three groups, including ethanol,acetic acid,2-methyl-l-propanol,3-methyl-1-butanol, glycerin and4H-Pyran-4-one,2,3-dihydro-3,5-dihydroxy-6-methyl-; Compared with control group, alcohols and ester material of plum wine were both lost after enzymatic debitterizing, and the relative contents of aldehydes and carboxylic acid had a large consumption; alcohols, aldehydes, ketone and ester material of plum wine were both lost after β-cyclodextrin inhibiting, and the relative contents of ketone and carboxylic acid had a large consumption.(3) The result of the sensory evaluation showed that without debitterizing the fermentation plum wine was fruity, but poor in flavor, and also with a heavier bitter; while the flavor and taste were improved after enzymatic and β-cyclodextrin processing, and would more likely to be acceptted by more consumers. Among them, the plum wine after enzymatic debitterizing was fruity, harmonious, comfortable, and had a better flavor and no obvious bitter, it tasted with appropriate with a little brewing taste; the plum wine after β-cyclodextrin inhibition was fruity, and had a better flavor and a litter bitter, its taste was suitable.The fermentation plum wine processed with amygdalase and β-cyclodextrin were compared by the amygdalin debitterizing rate, aroma compositions change and human body sensory evaluation, the conclusions are:amygdalase is more efficient than β-cyclodextrins to debitterize, thus the amygdalase debitterizing technology has a more promising utilization for industrial production.