枸杞酒酿造过程中的酚酸降解规律

Study on the degradation of phenolic acid during brewing of Lycium barbarum wine

枸杞酒发酵过程中酵母代谢产生一些有机酸、醇、醛、酮等复杂的物质,使发酵环境发生了变化,迫使酚酸物质在此环境下发生氧化、还原或与环境中的物质发生化学反应从而产生各种降解产物。实验测定了酚酸物质在发酵过程中含量的变化及降解产物,并通过模拟实验,验证枸杞发酵时可能产生的降解产物。结果表明,从实验所用枸杞中共检测出7种酚酸单体,发酵后酚酸降解产物共8种,这些物质大部分都在最不稳定的双键位置断裂,同时容易在羰基被还原、羟基被氧化,产生2,5-二甲基吡嗪、苯乙酮、4-乙基愈创木酚、丙酸、苯乙酸乙酯、2,4-二叔丁基苯酚、4-甲氧基苯乙烯和乙酸异戊酯。

During the fermentation of Lycium barbarum wine,various substances,mainly organic acids,alcohols,aldehydes and ketones,were produced from yeast metabolization.The fermentation environment keeps changing,and phenolic acids may be oxidized,reduced or reacted with other substances,yielding various degradation products.In this study,the changes of phenolic acid contents were evaluated during fermentation and the relative degradation products were identified,followed by a verification through simulation experiment.The results showed that seven kinds of phenolic acid monomers were detected and eight kinds of phenolic acid degradation products were obtained after fermentation.Most of these substances break at the most unstable double bond positions and are prone to reduction of carbonyl groups and oxidation of hydroxyl groups,producing 2,5-dimethylpyrazine,acetophenone,4-ethyl guaiacol,propionic acid,ethyl phenylacetate,2,4-tert-butylphenol,4-methoxystyrene and iso-amyl acetate.