Reference Number: 66
Lactobacillus plantarum LB1 and Lactobacillus rossiae LB5, isolated from wheat germ and selected based on the kinetics of acidification, were used as starters for the manufacture of sourdough fermented wheat germ. A bread containing sourdough fermented wheat germ as an ingredient (SFWGB) was compared to breads made with (raw wheat germ bread, RWGB) or without (wheat flour bread, WFB) raw wheat germ. The higher concentration of free amino acids mainly differentiated SFWGB from WFB and RWGB. The in vitro protein digestibility of WFB was the highest, even if sourdough fermentation of wheat germ attenuated the difference. Phytase and antioxidant activities of SFWGB were highest. The specific volume and cell- total areas were also the highest for SFWGB. As determined by texture profile analysis, the values of hardness, resilience and fracturability of breads containing wheat germ were lower than those found in WFB. The crust lightness showed a decrease from WFB to SFWGB. As determined by sensory analysis, SFWGB had mainly acid taste and flavour and resulted more salty. Sourdough fermented wheat germ is an ingredient able to enhance nutritional, texture and sensory properties of bread.
SIGNIFICANCE OF THIS STUDY
Wheat germ corresponds to 2–3% of the total weight of wheat kernel and is most often removed during the milling process since it adversely affects the keeping and processing quality of the flour. However, this is considered to be the most nutritional dense component of the kernel. The current study examines different flour varieties that include fermented wheat germ (freeze dried and added to white flour), raw wheat germ containing white flour and flour with no wheat germ (i.e plain white flour). Sourdough femented wheat germ had the highest antioxidant levels and mineral bioavailability due to high phrase activity. In addition to enhanced nutritional quality, freeze-dried sourdough fermented wheat germ enhanced the texture and sensory characteristics of the white bread.