Effect of controlled fermentation of Lactobacillus plantarum on sensory properties and staling of semi-loaf wheat bread

The aim of this study was evaluation of the effect of controlled fermentation of Lactobacillus plantarum on sensory properties and staling of semi-loaf wheat bread. For this purpose, the effect of fermentation times (8, 16, 24 h) and sugar contents (0.5, 1, 1.5%) on activity of mentioned starter in fermentation of wheat flour (with 76% extraction rate) in a split plot design were examined. After processing of semi-loaf breads with sourdough treatments, the staling of these breads were evaluated 2, 48 and 96 h after baking, based on their specific volume, crumb firmness (texture analysis) and amount of porosity (Image j method). According to the results, different fermentation times and sugar contents had significant effect (p≤0.05) on sourdough total titerable acidity and 96 h after baking, the lowest specific volume and the maximum amount of crumb firmness were observed in sample produced with sourdough after 16 h fermentation and 1% sugar content. The maximum amount of specific volume and the lowest crumb firmness were also observed in sample produced with sourdough after 8 h fermentation and 0.5% sugar content, 2 h after baking. Furthermore, the maximum amounts of porosity and the best sensory properties were obtained after 16 and 24 h sourdough fermentation and 1.5% sugar content, respectively. Based on these results, for production of sourdough bread with longer shelf life and better sensory properties, effective control of microbial starter and affective parameters on its fermentation is necessary.