Studies On Effects Of Wolfberry Wine Fermentation On Carotenoids

Wolfberry wine is a wine brewed with wolfberry juice as raw material,Chinese wolfberry is abundant of carotenoids, which have many conjugated double bonds and with high activity to some factors like the oxygen, light, high temperature, etc. Carotenoids are prone to oxidation and isomerization reaction, it can easily degrade in the food processing and storage course, norisoprenoids degraded by carotenoids have important effects on aromas of medlar wine,study on degradation law of carotenoids during wolfberry wine fermentation will help to improve the aroma of medlar wine.The influences of pectinase, SO2, pH and high pressure sterilization on carotenoids of medlar juice during fermentation pre-treatment were researched in this task firstly, and the contents of zeaxanthine, Zeaxanthin dipalmitate, β-carotene and total carotenoids were measured by employing HPLC(high performance liquid chromatography). The variation patterns of carotenoids components were analyzed and a kinetic equation of every kind of carotenoids was also forged during fermentation. The results were as below:(1)Influences of the enzymolysis, SO2 and pH on carotenoid substances were analyzed.The results showed that degradation of pectin by pectinase that can promote carotenoids be released from cell wall and produce -COOH, resulting in carotenoids’ break down.The content of Zeaxanthin dipalmitate, β-carotene can be increased, but the zeaxanthin content will be reduced after treated with SO2. When pH of 3.0～3.5, content of Carotenoids are declining as pH lower, The Influence of the 3.0-3.5 (pH) on β-carotene is not obvious. High pressure sterilization has significant damage to the carotenoids.(2) Through Analyzing the variety of carotenoids in the course of ferment, we can find that the β-carotene showed the trend of decreasing first and increasing then. The total amount of Zeaxanthin dipalmitate and carotenoids both became lower continuously, however, it increased in the late period of ferment. In the case of Zeaxanthin,it showed the trend of decreasing first and increasing following this, then came rapid degradation, and finally it had the irregular trend of ascend by small amplitude. The results show that yeast growth has an effect on carotenoids degradation in the process of wolfberry wine fermentation.(3)By establishing dynamic models of all kinds of carotenoids in ferment, we have come to the ultimateness that:Degradation equation of Zeaxanthin dipalmitate during fermentation: Degradation equation of total carotenoids during fermentation:...