Abstract：
The plum seed protein isolates (PSPI) were used to prepare a gel by probiotics fermentation. The effects of fermentation time (from 0 to 12 h) on the physicochemical properties of PSPI gel were evaluated. The results showed that PSPI started to form a gel after 6 h of fermentation, as evidenced by a decrease in pH from 6.6 to 5.2, an increase in particle size from 10 μm to 40 μm, appearance of a new peak with retention time of 10 min in gel filtration high-performance liquid chromatography, and formation of aggregation and porous structure observed by fluorescence and scanning electron microscope. The PSPI gel from 9 h of fermentation exhibited the highest viscosity (318 Pa.s), storage modulus (18,000 Pa), water holding capacity (37 %), and gel strength (21.5 g) due to stronger molecular interactions such as hydrogen bond, electrostatic, hydrophobic interaction and disulfide bond. However, increasing fermentation time over 9 h led to disrupture of PSPI gel. Furthermore, the subunit around 15 kDa of PSPI disappeared after fermentation, indicating that the formation of PSPI gel was induced by both acidification and partial hydrolysis. Our results suggest that PSPI can provide an alternative for developing plant-based gel products.
摘要：
利用李子籽分离蛋白(PSPI)通过益生菌发酵制备凝胶。评价了发酵时间(0～12h)对PSPI凝胶理化性质的影响。结果表明，PSPI在发酵6小时后开始形成凝胶，pH值从6.6降低到5.2，粒径从10μm增加到40μm，在凝胶过滤高效液相色谱中出现一个保留时间为10分钟的新峰，荧光和扫描电子显微镜观察到聚集和多孔结构的形成。发酵9h的PSPI凝胶显示出最高的粘度（318Pa。s),储能模量(18,000Pa)，持水量(37%)，和凝胶强度（21.5克），由于更强的分子相互作用，如氢键，静电,疏水相互作用和二硫键。然而,发酵时间超过9小时导致PSPI凝胶的破坏。此外，PSPI约15kDa的亚基在发酵后消失，表明PSPI凝胶的形成是由酸化和部分水解引起的。我们的结果表明，PSPI可以为开发基于植物的凝胶产品提供替代方案。
