Abstract：
This study investigated the effect of in situ produced water-soluble α-glucan (LcWSG) and water-insoluble α-glucan (LcWIG) from Leuconostoc citreum SH12 on the physicochemical properties of fermented soymilk. α-Glucans produced by Leuc. citreum SH12 improved water-holding capacity, viscosity, viscoelasticity and texture of fermented soymilk. Gtf1365 and Gtf836 of the five putative glucansucrases were responsible for synthesizing LcWSG and LcWIG during soymilk fermentation, respectively. Co-fermentation of soymilk with Gtf1365 and Gtf836 and non-exopolysaccharide-producing Lactiplantibacillus plantarum D1031 indicated that LcWSG effectively hindered the whey separation of fermented soymilk by increasing viscosity, while LcWIG improved hardness, springiness and accelerated protein coagulation. Fermented soymilk gel formation was mainly based on hydrogen bonding and hydrophobic interactions, which were promoted by both LcWSG and LcWIG. LcWIG has a greater effect on α-helix to β-sheet translation in fermented soymilk, causing more rapid protein aggregation and thicker cross-linked gel network. Structure-based exploration of LcWSG and LcWIG from Leuc. citreum SH12 revealed their distinct roles in the physicochemical properties of fermented soymilk due to their different ratio of α-1,6 and α-1,3 glucosidic linkages and various side chain length. This study may guide the application of the water-soluble and water-insoluble α-glucans in fermented plant protein foods for their quality improvement.
摘要：
这项研究研究了原位产生的水溶性α-葡聚糖（LcWSG）和水不溶性α-葡聚糖（LcWIG）对发酵豆乳的理化性质的影响。Leuc生产的α-葡聚糖。柑橘SH12提高了保水能力，粘度,发酵豆浆的粘弹性和质地。五种推定的葡聚糖蔗糖酶的Gtf1365和Gtf836负责在豆浆发酵过程中合成LcWSG和LcWIG，分别。豆乳与Gtf1365和Gtf836以及非产胞外多糖的植物乳杆菌D1031的共发酵表明，LcWSG通过增加粘度有效地阻碍了发酵豆乳的乳清分离，虽然LcWIG改善了硬度，弹性和加速蛋白质凝固。发酵豆乳凝胶的形成主要基于氢键和疏水相互作用，由LcWSG和LcWIG推广。LcWIG对发酵豆浆中α-螺旋到β-折叠的翻译有更大的影响，导致更快速的蛋白质聚集和更厚的交联凝胶网络。Leuc对LcWSG和LcWIG的基于结构的探索。citreumSH12揭示了它们在发酵豆浆的理化性质中的不同作用，因为它们的α-1,6和α-1,3糖苷键的比例不同以及不同的侧链长度。本研究可指导水溶性和水不溶性α-葡聚糖在植物蛋白发酵食品中的应用，以提高其品质。
