Background and objective: Sourdough fermentation with interactions between lactic acid bacteria and yeasts, is considered to play a key role in producing bakery products with improved flavor, texture and shelf-life properties. This research focused on evaluation of acidification properties of different starter cultures in liquid sourdough fermentation and selecting an appropriate inoculum based on quality and shelf-life properties of the resultant bread.
Material and methods: Liquid sourdough samples were fermented by cultures including L.casei and S.cerevisiae (T1), L.fermentum and S.cerevisiae (T2), L.casei, L.fermentum and S.cerevisiae (T3) and adde to bread doughs (15% w/w). Technological properties (moisture content, specific volume and organoleptic properties) and shelf-life of the sourdough breads were compared with those of a control bread.
Results: Sourdoughs fermented by inoculums T1 and T3 had a similar pH-lowering rate (there were only small differences). Inoculum T3 showed the highest acidification rate. In comparison, inoculum T2 showed a lower acidification rate (pH> 4). Liquid sourdough breads had higher specific volumes as compared to the control bread, and sourdough bread T3 ranked first organoleptically. Sourdough breads (T1 and T3) had a lower staling rate than the control value, and bread T3 showed a higher staling rate than T1 (p< 0.05).
Conclusion: Sourdough addition can improve organoleptic properties–specific volume and shelf-life–of the breads.. Based on acidification properties and sensory analysis, inoculum L.casei, L.fermentum and S.cerevisiae produce the most desirable effects.