热稳定冰结构蛋白对小麦淀粉凝胶冻融稳定性的影响

Influence of Thermalstable Ice-Structuring Proteins Extracted from Oat Flour and Chinese Privet Leaves on Freeze-Thaw Stability of Wheat Starch Gels

研究燕麦粉和女贞叶中热稳定冰结构蛋白(TSISP)对淀粉凝胶冻融稳定性的影响。应用差示扫描量热仪(DSC)、扫描电子显微镜(SEM)和质构仪分别研究燕麦粉、女贞叶TSISP对淀粉凝胶冻融后析水率、可冻结水含量、超微结构、硬度及弹性的影响。结果表明:冻融过程显著地增加淀粉凝胶析水率、可冻结水含量,严重地破坏淀粉凝胶超微结构、增加孔洞尺寸、减小孔洞均匀性,最后导致淀粉凝胶硬度明显增大,弹性明显减小;而燕麦粉和女贞叶中TSISP的添加显著地减小淀粉凝胶冻融后析水率和可冻结水含量,同时显著地改善淀粉凝胶超微结构,使得淀粉凝胶孔洞增大幅度明显得到抑制,孔洞均匀性更好,结果也对淀粉凝胶质构产生明显的改善效果,延缓硬度的增加和弹性的减小,使得冻融后淀粉凝胶的总体品质得以提高。

The effect of thermostable ice-structuring proteins extracted from oat flour and Chinese Privet （Ligustrum vulgare） leaves separately added at 0.5% on the freeze-thaw stability of wheat starch gels was investigated. The syneresis, freezable water content, microstructure and texture of starch gels after going through different freeze-thaw cycles were analyzed using centrifugation, differential scanning calorimetry, scanning electron microscopy and texture analyzer, respectively. The results showed that as freeze-thaw process happened repeatedly, the syneresis and freezable water content of starch gels increased obviously, the microstructure was damaged seriously, ice cell cavities became larger and uneven, the hardness increased markedly, and the springness decreased significantly. The introduction of TSISP extracted from oat flour and Chinese Privet （Ligustrum vulgare） leaves into wheat starch gels improved the freeze-thaw stability, which was indicated by a significant decrease in syneresis, freezable water content, the size of ice cell cavities and springiness and an increase in hardness.