Effect of heat‐treated wheat germ on dough properties and crackers quality

Wheat germ is one of the by‐products of the milling industry. However, wheat germ has a limited shelf life because its unsaturated fatty acids are prone to oxidation and rancidity during storage. This study aims to analyze the influence of heat‐treated wheat germ on dough properties and cracker quality. Different substitution levels of wheat flour were evaluated. Summary This study aims to analyse the influence of heat‐treated wheat germ on dough properties and cracker quality. Different substitution levels of wheat flour were evaluated (0%, 10%, 20% and 30%). Dough rheological properties and stress relaxation behaviour were determined. Chemical characteristics, baking performance, texture, water activity and sensory analyses were performed on crackers. Wheat germ weakened the dough structure. The following mechanisms were suggested to explain this weakening effect: the addition of wheat germ diluted gluten; flour components and germ competed for water and decreased the water availability for gluten formation; and germ particles physically disrupted the continuity of the gluten network. Nevertheless, good quality crackers were obtained and their nutritional value was improved, with remarkable increments in protein, fibre and mineral contents. Also, high acceptance in sensory evaluation was recorded at substitution levels of 20% and 30% of germ, compared to control sample (0%).