Department of Food Science, University of Wisconsin-Madison, 1605 Linden Drive, Madison, WI 53706, United States.
Department of Food Science, University of Wisconsin-Madison, 1605 Linden Drive, Madison, WI 53706, United States.
Food Chem. 2018 Oct 30;264:319-325. doi: 10.1016/j.foodchem.2018.05.045. Epub 2018 May 9.
A simple mild process to remove phospholipids in soy protein isolate has been developed. The method includes two steps: A 5% soy protein isolate solution is concurrently treated with 0.5-1.5 μkat phospholipase A/g protein and 10 mmol/l β-cyclodextrin for 4 h at 43 °C, pH 8.0; secondly, soy protein is separated from the treated solution by precipitating at pH 4.5. The treatment removed more than 92% of the off-flavour precursors in SPI. Comparing α-, β-, and γ-cyclodextrins, α-cyclodextrin was more effective (>95% removal of precursors) than β-cyclodextrin, while γ-cyclodextrin essentially had no effect. Under accelerated storage conditions at 45 °C for 90 days, the rate of hexanal production in the treated SPI was 12-times slower than that in the untreated SPI. The treatment lowered the thermal denaturation temperature and enthalpy of denaturation of soy proteins but not its solubility, indicating that the treatment caused some structural changes in soy proteins.
已经开发出一种简单温和的方法来去除大豆分离蛋白中的磷脂。该方法包括两步：将 5%的大豆分离蛋白溶液与 0.5-1.5μkat 磷脂酶 A/克蛋白和 10mmol/l β-环糊精在 43°C、pH8.0 下同时处理 4 小时；其次，通过在 pH4.5 下沉淀将处理后的溶液中的大豆蛋白分离出来。该处理去除了 SPI 中超过 92%的异味前体。与 α-、β-和 γ-环糊精相比，α-环糊精比 β-环糊精更有效（去除前体超过 95%），而 γ-环糊精基本上没有效果。在 45°C 加速储存 90 天的条件下，处理后的 SPI 中己醛的生成速率比未处理的 SPI 慢 12 倍。该处理降低了大豆蛋白的热变性温度和变性焓，但不降低其溶解度，表明该处理导致大豆蛋白发生了一些结构变化。
