不同月份豆腐柴叶果胶理化性质差异研究

Study on the Difference of the Physicochemical Properties of Pectin from Premna microphylla Turcz Leaves in Different Months

为探究不同月份豆腐柴叶果胶特性差异,寻求不同月份"树叶凉粉"品质参差不齐的原因,提高豆腐柴叶果胶的应用价值,本文主要采用主成分分析法综合评价了不同月份(5~10月)豆腐柴叶果胶得率、主要成分、粘均分子量、乳化性、凝胶性等理化性质。结果表明:果胶得率为4.24%~18.24%,5~9月得率高于15%;半乳糖醛酸含量为73.73%~81.96%,6~9月含量较高;5~9月粘均分子量随月份增加呈增大趋势,10月有所降低。5~8月得到的果胶粉末呈淡黄色,9月和10月呈淡黄夹灰白色。乳化活性和乳化稳定性均高于50%,优于橘皮果胶标品;凝胶特性差异明显,7~9月果胶凝胶性能良好。综合评分从高到低为:9月>7月>8月>10月>6月>5月,说明不同月份豆腐柴叶果胶品质差异较大,7~9月豆腐柴叶果胶综合得分明显高于其他月份,更适合于果胶的提取利用。

In order to explore the different characteristics of pectin from Premna microphylla Turcz leaves in different months,seek the reasons for the uneven quality of"leaf jelly"in different months,and improve the application value of pectin,the principal component analysis method was used to evaluate the yield rate,main components,viscosity average molecular weight,emulsifying properties and gel properties of pectin in different months(from May to October)in this paper.The results showed that the pectin yield rate was ranged from 4.24%to 18.24%,the percentages from May to September were higher than 15%.And the galacturonic acid content was from 73.73%to 81.96%,the content was higher from June to September.The viscosity average molecular weight increased with the month from May to September,and decreased in October.The obtained pectin powder was pale yellow from May to August and pale yellow with grayish white in September and October.Emulsifying activity and emulsifying stability were higher than 50%,which was superior to the orange peel pectin standard.There were significant differences in gel properties and gel performance of pectin from July to September was better.The order of the comprehensive score from high to low was September>July>August>October>June>May,indicating that the quality of pectin varied greatly from month to month,and the pectin from Premna microphylla Turcz leaves from July to September was more suitable for the extraction and utilization,since the comprehensive score was higher obviously than other months.