Wally-Vallim Ana Paula, Vanier Nathan Levien, Zavareze Elessandra da Rosa, Zambiazi Rui Carlos, de Castro Luis Antônio Suita, Schirmer Manoel Artigas, Elias Moacir Cardoso
Depto. de Ciência e Tecnologia Agroindustrial, Univ. Federal de Pelotas, 96010-900, Capão do Leão, Brazil; Inst. Federal Sul-Riograndense, Campus Pelotas - Visconde da Graça, 96060-290, Pelotas, Brazil.
J Food Sci. 2014 Jul;79(7):E1351-8. doi: 10.1111/1750-3841.12506. Epub 2014 Jun 3.
Soybeans were hydrothermally treated at 2 different temperatures (40 °C and 60 °C) and for 4 different hydration times (4, 8, 12, and 16 h) to (i) increase the isoflavone aglycone content in a soy protein isolate and (ii) evaluate the changes in thermal, functional, and structural properties of a soy protein isolate as a function of hydrothermal treatment conditions. Our study is the first to evaluate aglycone content, extraction yield, β-glucosidase activity, differential scanning calorimetry, protein digestibility, scanning electron microscopy, water absorption capacity (WAC), foaming capacity (FC), and foaming stability of soy protein isolates prepared from hydrothermally treated soybeans. For aglycone enhancement and the extraction yield maintenance of soy protein isolates, the condition of 40 °C for 12 h was the best soybean hydrothermal treatment. The structural rearrangement of proteins that occurred with the hydrothermal treatment most likely promoted the capacity of proteins to bind to aglycone. Moreover, the structure shape and size of soy protein isolates verified by scanning electron microscopy appears to be related to the formation of hydrophobic surfaces and hydrophobic zones at 40 °C and 60 °C, respectively, affecting the protein digestibility, WAC, and FC of soy protein isolates.
The aglycone content in the soy protein isolate can be improved with the hydrothermal treatment of soybeans. The temperature and time used for hydrothermal treatment must be selected in order to achieve a soy protein isolate with high aglycone content, extraction yield, and functionality. This technology is suitable for providing healthier soy protein isolates for food industry with improved functional and structural properties.
大豆在2个不同温度（40℃和60℃）和4个不同水合时间（4、8、12和16小时）下进行水热处理，以（i）提高大豆分离蛋白中的异黄酮苷元含量，以及（ii）评估大豆分离蛋白的热、功能和结构性质随水热处理条件的变化。我们的研究首次评估了由水热处理大豆制备的大豆分离蛋白的苷元含量、提取率、β-葡萄糖苷酶活性、差示扫描量热法、蛋白质消化率、扫描电子显微镜、吸水能力（WAC）、发泡能力（FC）和发泡稳定性。对于大豆分离蛋白的苷元增强和提取率维持，40℃处理12小时的条件是最佳的大豆水热处理条件。水热处理过程中发生的蛋白质结构重排最有可能促进蛋白质与苷元结合的能力。此外，通过扫描电子显微镜验证的大豆分离蛋白的结构形状和大小似乎分别与40℃和60℃下疏水表面和疏水区域的形成有关，影响大豆分离蛋白的蛋白质消化率、WAC和FC。
大豆的水热处理可以提高大豆分离蛋白中的苷元含量。必须选择用于水热处理的温度和时间，以获得具有高苷元含量、提取率和功能的大豆分离蛋白。该技术适用于为食品工业提供具有改善的功能和结构性质的更健康的大豆分离蛋白。
