辣木叶茶4种发酵方式不同发酵阶段化学成分与品质变化及其相关性分析

Changes and Correlations of Chemical Components and Quality of Moringa oleifera Leaf Tea at Different Stages of Four Fermentation Methods

采用自然发酵、酵母发酵、根霉发酵与黑曲霉发酵四种方式发酵自制辣木叶茶,研究了其不同发酵阶段样的色泽指标、感官品质与化学成分变化,并分析它们之间的相关性。结果表明:随着发酵时间的延长,四种方式辣木叶茶发酵样的化学成分与品质发生了明显的变化,发酵16 d后,其感官品质有所提升,辣木可溶性蛋白、咖啡碱含量有所升高,多酚、黄酮、多糖及水浸出物含量有所下降,评价茶汤色泽的△E^(*)值、a^(*)值、b^(*)值指标随翻堆次数的增加而有所升高。其中辣木叶茶黑曲霉发酵效果较好,其发酵16 d的四翻样感官品质最好,其多酚、黄酮、可溶性蛋白、多糖、咖啡碱、水浸出物含量分别为13.48、10.99、16.46、27.38、2.39与342.70 mg/g,茶汤色泽指标a^(*)值、b^(*)值、△E^(*)值分别为15.66、28.48与36.42。辣木叶茶不同发酵阶段样的水浸出物(Y)含量与多酚(X_(1))、可溶性蛋白(X_(3))与多糖(X4)的含量呈极显著正相关,相关系数分别为0.8821、0.7598与0.7240,它们之间的线性回归方程为Y=15.8337+0.6793X1+0.2360X3+0.0897X4。研究结果为辣木叶发酵茶产品开发及这一资源的开发利用提供一定的实践和数据参考。

Moringa oleifera leaf tea were fermented by natural fermentation,yeast fermentation,Rhizopus fermentation and Aspergillus niger fermentation.Color indexs,sensory quality and chemical components of Moringa oleifera leaf tea samples in different fermentation stages were determined,and correlations among chemical components were analyzed.Results showed that the main chemical components and quality of Moringa oleifera leaf tea samples in different fermentation stages were converted obviously.When Moringa oleifera leaf tea was fermented for 16 days,its sensory quality had been improved,and the contents of soluble protein and caffeine increased,while the contents of polyphenol,flavonoid,polysaccharide and water extract decreased.The color indexes△E^(*)value,a^(*)value and b^(*)value of soups of Moringa oleifera leaf tea fermented samples increased with the increase of pile-up times.The fourth pile-up sample of Moringa oleifera leaf tea fermented by Aspergillus niger had the best sensory quality,the contents of its polyphenol,flavonoid,soluble protein,polysaccharide,caffeine and water extract were 13.48,10.99,16.46,27.38,2.39 and 342.70 mg/g,and the color indexes a^(*)value,△E^(*)value and b^(*)value of its soup were 15.66,28.48 and 36.42,respectively.The contents of water extracts(Y)of different fermented samples of Moringa oleifera leaf tea were significantly positively correlated with the contents of polyphenol(X_(1)),soluble protein(X_(3))and polysaccharide(X4),their correlation coefficients were 0.8821,0.7598 and 0.7240,respectively,and the regression equation was Y=15.8337+0.6793X1+0.2360X3+0.0897X4.The results of this study can provide the references for exploitation of Moringa oleifera leaf fermentation tea and utilization of this resource.