Technische Universität München, Lehrstuhl für Technische Mikrobiologie, Weihenstephaner Steig 16, 85350 Freising, Germany.
Food Microbiol. 2012 Dec;32(2):286-94. doi: 10.1016/j.fm.2012.07.002. Epub 2012 Jul 20.
Currently hydrocolloids are applied as baking aids in order to enhance the quality of gluten-free bread. Microbial exopolysaccharides (EPS) can also have a positive impact on gluten-free baked goods. Provided that yields are sufficient, in situ produced EPS may enable clean (additive free) labels. Thus, in situ EPS optimization was conducted to achieve high amounts of EPS in gluten-free sourdoughs. The influence of flours, dough yield, cell counts, sucrose concentration and sucrose fed-batch were investigated for Lactobacillus (L.) animalis TMW 1.971, Lactobacillus reuteri TMW 1.106 and Lactobacillus curvatus TMW 1.624. Maximal yields of 17.93 g EPS kg(-1) flour were obtained with L. animalis TMW 1.971 in buckwheat core doughs, 15.69 g EPS kg(-1) with L. reuteri TMW 1.106 in quinoa, and 16.28 g EPS kg(-)(1) flour with L. curvatus TMW 1.624 in buckwheat sourdoughs. This study evidences that EPS amounts can be manifolded to reach effectual levels through optimization and corroborate the application of EPS-forming starter cultures as a promising approach to improve gluten-free baked goods.
目前，水胶体被用作烘焙助剂，以提高无麸质面包的质量。微生物胞外多糖 (EPS) 也可以对无麸质烘焙食品产生积极影响。只要产量足够，原位产生的 EPS 可以实现清洁（无添加剂）标签。因此，进行了原位 EPS 优化，以在无麸质酸面团中获得大量 EPS。研究了乳杆菌 (L.) animalis TMW 1.971、Lactobacillus reuteri TMW 1.106 和 Lactobacillus curvatus TMW 1.624 的面粉、面团得率、细胞计数、蔗糖浓度和蔗糖分批进料对 EPS 的影响。在荞麦芯面团中，L. animalis TMW 1.971 可获得最大的 17.93 g EPS kg(-1) 面粉，在藜麦中，L. reuteri TMW 1.106 可获得最大的 15.69 g EPS kg(-1) 面粉，在荞麦酸面团中，L. curvatus TMW 1.624 可获得最大的 16.28 g EPS kg(-1) 面粉。本研究证明，通过优化可以将 EPS 量成倍增加，达到有效水平，并证实了 EPS 形成的启动培养物的应用是改善无麸质烘焙食品的一种有前途的方法。
