Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Food Science & Nutritional Engineering, China Agricultural University, Beijing 100083, China.
Inner Mongolia Mengniu Dairy (Group) CO., Ltd., Hohhot 750306, China.
Molecules. 2018 Jul 4;23(7):1632. doi: 10.3390/molecules23071632.
In this study, the effect of trisodium citrate on the textural properties and microstructure of acid-induced, transglutaminase-treated micellar casein gels was investigated. Various concentrations of trisodium citrate (0 mmol/L, 10 mmol/L, 20 mmol/L, and 30 mmol/L) were added to micellar casein dispersions. After being treated with microbial transglutaminase (mTGase), all dispersions were acidified with 1.3% (/) gluconodelta-lactone (GDL) to pH 4.4⁻4.6. As the concentration of trisodium citrate increased from 0 mmol/L to 30 mmol/L, the firmness and water-holding capacity increased significantly. The final storage modulus (G′) of casein gels was positively related to the concentration of trisodium citrate prior to mTGase treatment of micellar casein dispersions. Cryo-scanning electron microscopy images indicated that more interconnected networks and smaller pores were present in the gels with higher concentrations of trisodium citrate. Overall, when micellar casein dispersions are treated with trisodium citrate prior to mTGase crosslinking, the resulted acid-induced gels are firmer and the syneresis is reduced.
在这项研究中，研究了柠檬酸三钠对酸诱导的转谷氨酰胺酶处理的胶束酪蛋白凝胶的质构特性和微观结构的影响。向胶束酪蛋白分散液中添加不同浓度的柠檬酸三钠（0 mmol/L、10 mmol/L、20 mmol/L 和 30 mmol/L）。用微生物转谷氨酰胺酶（mTGase）处理后，所有分散液均用 1.3%（/）葡萄糖酸-delta-内酯（GDL）酸化至 pH 4.4⁻4.6。随着柠檬酸三钠浓度从 0 mmol/L 增加到 30 mmol/L，硬度和持水力显著增加。经 mTGase 处理的胶束酪蛋白分散液中柠檬酸三钠的浓度与酪蛋白凝胶的最终储能模量（G′）呈正相关。冷冻扫描电子显微镜图像表明，在柠檬酸三钠浓度较高的凝胶中存在更多的相互连接的网络和更小的孔。总的来说，当胶束酪蛋白分散液在 mTGase 交联之前用柠檬酸三钠处理时，得到的酸诱导凝胶更硬，离析减少。
