Zadeike Daiva, Gaizauskaite Zydrune, Basinskiene Loreta, Zvirdauskiene Renata, Cizeikiene Dalia
Department of Food Science and Technolgy, Faculty of Chemical Technology, Kaunas University of Technology, 50254 Kaunas, Lithuania.
Gels. 2024 Oct 8;10(10):641. doi: 10.3390/gels10100641.
This study focuses on evaluating the efficiency of acid-tolerant bacteria encapsulated in an alginate-based gel matrix during repeated sourdough fermentation cycles, as well as their preservation during storage and throughout baking at high temperature. A double-coating procedure was applied, involving the encapsulation of bacterial cells in calcium alginate, which was further coated with chitosan. The encapsulation efficiency (EE) did not show significant difference between alginate and alginate-chitosan (97.97 and 96.71%, respectively). The higher number of bacteria was preserved in double-coated microbeads, with survivability rates of 89.51% and 96.90% in wet and dried microbeads, respectively. Encapsulated bacteria demonstrated effective fermentation ability, while double gel-coated cells exhibited slower acidification during sourdough fermentation, maintaining higher efficiency in the second fermentation cycle. The addition of freeze-dried, alginate-based gel-encapsulated bacteria (2-4%, / flour) significantly ( < 0.05) improved bread quality and extended its shelf life. A double-layer coating (alginate-chitosan) can be introduced as an innovative strategy for regulating the release of lactic acid bacteria and optimizing fermentation processes. Powdered alginate or alginate-chitosan gel-based microcapsules, at appropriate concentrations, can be used in the production of baked goods with acceptable quality and sensory properties, achieving a lactic acid bacteria count of approximately 10 CFU/g in the crumb, thereby meeting the standard criteria for probiotic bakery products.
本研究着重评估包封在海藻酸盐基凝胶基质中的耐酸细菌在重复酸面团发酵循环过程中的效率，以及它们在储存期间和高温烘焙全过程中的保存情况。采用了一种双重包衣程序，即将细菌细胞包封在海藻酸钙中，再用壳聚糖进一步包衣。海藻酸盐和海藻酸盐-壳聚糖之间的包封效率（EE）没有显著差异（分别为97.97%和96.71%）。双重包衣微珠中保存的细菌数量更多，湿微珠和干微珠中的存活率分别为89.51%和96.90%。包封的细菌表现出有效的发酵能力，而双重凝胶包衣的细胞在酸面团发酵过程中酸化较慢，在第二次发酵循环中保持较高效率。添加冻干的、海藻酸盐基凝胶包封的细菌（2-4%，/面粉）显著（<0.05）改善了面包品质并延长了其保质期。双层包衣（海藻酸盐-壳聚糖）可作为一种创新策略引入，用于调节乳酸菌的释放并优化发酵过程。适当浓度的粉末状海藻酸盐或海藻酸盐-壳聚糖凝胶基微胶囊可用于生产具有可接受品质和感官特性的烘焙食品，在面包心实现约10 CFU/g 的乳酸菌计数，从而符合益生菌烘焙产品的标准。
