不同预处理对豆腐柴叶果胶理化性质的影响

为提高原料利用率和果胶得率,探究不同预处理对豆腐柴叶果胶理化性质的影响,寻求较优的预处理方式,本文主要研究了不同预处理方式(蒸汽、微波、酸浸泡、烫漂、冷冻)对豆腐柴叶果胶得率、主要成分、表面形态、结构特性的影响。结果表明:豆腐柴叶果胶得率为8.95%～19.32%,从大到小依次为:蒸汽>微波>酸浸泡>未处理>烫漂>冷冻;半乳糖醛酸含量为69.08%～89.76%,从高到低依次为:蒸汽>微波>未处理>酸浸泡>烫漂>冷冻;得到的果胶粉末蒸汽为白色,微波、烫漂为淡黄色,未处理、酸浸泡、冷冻为浅棕色。扫描电镜结果表明,除蒸汽预处理外,其它预处理豆腐柴叶果胶表面形态粗糙。红外光谱发现,不同预处理对果胶主要官能团并无明显影响。蒸汽预处理得到的豆腐柴叶果胶得率和纯度最高、颜色最白,其表面形态光滑。各理化指标综合表明蒸汽处理是提取豆腐柴叶果胶的最佳预处理方式。

Effects of Different Pretreatments on Physicochemical Properties of Pectin from Premna microphylla Turcz Leaves

This paper was to improve raw material utilization and pectin yield,explore the effects of different pretreatments on the physical and chemical properties of pectin from Premna microphylla Turcz leaves,and seek a better pretreatment method.The effects of different pretreatments(steam,microwave,acid soaking,blanching and freezing) on the yield,main compositions,surface morphology and structural properties of pectin were considered.The results showed that the yield of pectin was ranged from 8.95% to 19.32%,the rank was steam > microwaves > acid soaking > non-treatment > blanching > freezing.And the galacturonic acid content was from 69.08% to 89.76%,the rank was steam > microwaves > non-treatment > acid soaking >blanching > freezing.The obtained pectin powder were white by steam,light yellow by microwaves and blanching,and light brown by non-treatment,acid soaking and freezing.The results of scanning electron microscopy indicated that the surface morphology of pectin was rough except for steam.Infrared(IR) spectroscopy discovered that different pretreatments had little impact on the primary functional groups.The pectin by steam pretreatment had the biggest yield and purity,the whitest color,and the smooth surface morphology.The combination of physical and chemical indicators suggested that steam was the optimal pretreatment method for extracting pectin from Premna microphylla Turcz leaves.