Enhancement of Technological Functionality of White Wheat Bread Using Wheat Germ Sourdough Along with Dehydrated Spinach Puree

Bread enrichment with fiber-rich leafy vegetables and fermented by-products of milling has gained more attention in recent years. In the present study, the antifungal lactic acid bacterium isolated from Tarkhineh was used as starter culture in controlled wheat germ sourdough in order to improve quality and safety of the white wheat bread containing wheat germ sourdough along with dehydrated spinach puree. The optimized formulation (10% wheat germ sourdough and 20% dehydrated spinach puree, which were replaced by wheat flour) was determined based on the crumb softness of the enriched breads. Then, the quality characteristics of the supplemented breads were studied in terms of textural properties, antioxidant activity, surface moldiness, phytic acid content and organoleptic acceptability. The sequencing of polymerase chain reaction products led to the identification of Lactococcus lactis as the selected antifungal lactic acid bacterium isolate. Texture profile analysis revealed the significant effect (P< 0.05) of wheat germ sourdough and dehydrated spinach puree on crumb hardness and loaf specific volume of the produced breads. Bread containing wheat germ sourdough along with dehydrated spinach puree had the highest radical scavenging activity. Green zone of Asprgillus flavus growth on wheat germ sourdough supplemented bread and phytic acid content of the aforementioned sample were also remarkably lower than the others. Furthermore, there was no significant difference between bread enriched with wheat germ sourdough and wheat germ sourdough along with dehydrated spinach puree in terms of sensory acceptability compared to the control sample.