The Impact Of Carotenoids Degradation In Fermentation Wolfberry Wine On Aroma Compounds

Carotenoids is one of the main active substances in Chinese wolfberry. During fermentation of Chinese wolfberry wine, carotenoids, through a series of complex chemical reactions, degrads to norisoprenoids compounds, which is the peculiar flavor components of the Chinese wolfberry wine or other fruit wine. Norisoprenoids compounds have important contribution to Chinese wolfberry wine aroma quality.The main contents of this paper are as follows:1. Using dry and fresh Chinese wolfberry as raw fermentation materials. Through contrast experiment, compares the type and content changes of norisoprenoids compounds degraded from carotenoids in different pretreatment conditions before fermentation. Use different pretreatment conditions, such as adding pectinase, changing the solution’s pH, adding SO2, using different sterilization method, etc. Observe the changes of norisoprenoids compounds degraded from carotenoids broken down, to determine the influence of different fermentation factors on the wine aroma formation.2. Analyzing the changes of content and form of norisoprenoids during Chinese wolfberry wine fermentation, combined with the change rule of carotenoids degradation during the fermentation, investigated the relevance between the different content and variety of norisoprenoids compounds and the flavor Chinese wolfberry wine.3. Set up Chinese wolfberry wine aroma quality evaluation model, help to understand the norisoprenoids compounds’ contribution to Chinese wolfberry wine aroma.The main results were as follows:(1) The pretreatment process had different influence on the norisoprenoids compounds degraded from carotenoids in Chinese wolfberry juice. The content of norisoprenoids compounds increased with adding pectinase. With the solution’s pH changed, found that the acidic environment droped the production of norisoprenoids compounds. Low concentration of SO2 could promote the production of norisoprenoids compounds, and high concentration of SO2 made norisoprenoids compounds lower. High pressure sterilization made norisoprenoids compounds increasesing. Detect 10 norisoprenoids compounds in this experiment.(2) After filtering the yeast in fermented Chinese wolfberry wine, most liposoluble carotenoids also left in the Chinese wolfberry slag. Carotene partly degradated during the fermentation process. Detect 8 norisoprenoids compounds in fermented Chinese wolfberry wine. The content of norisoprenoids in Chinese wolfberry wine aroma components showed a trend of decrease, while the species tended to be stable, primarily existed as β-ionone.(3) Based on principal component analysis (PCA), Chinese wolfberry wine aroma quality evaluation model was built. Found 7 norisoprenoids compounds had contribution to Chinese wolfberry wine aroma, typically represented the Chinese wolfberry’s odor.