Studies on heat stabilized wheat germ and its influence on rheological characteristics of dough

• Published in: European food research & technology 2007-01, Vol.224 (3), p.365-372
• Main Authors: Srivastava, Alok K, Sudha, M. L, Baskaran, V, Leelavathi, K
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Cereal and baking product industries; Enzymes; Food industries; Food science; Fundamental and applied biological sciences. Psychology; Heat treating; Heat treatment; Nutrition; Rheology; Sensory perception
• ISSN: 1438-2377; 1438-2385
• DOI: 10.1007/s00217-006-0317-x

Wheat germ, a nutrient dense by-product has a very poor shelf life. In order to improve its keeping quality, so that it can be used into different products, various heat treatments were tried and studied to investigate their influence on proximate composition as well as on the rheological characteristics of wheat flour dough. Different heat treatments have shown insignificant effect on proximate composition of wheat germ. Retention of vitamin E was greater in steamed and dried germ. Except for fluidized bed dried germ, all the heat treatments employed completely inactivated the lipase enzyme, whereas the lipoxygenase enzyme was inactivated to an extent of 80-92%. Quality evaluation of germ samples during 60 days storage indicated that steamed and dried germ retained the sensory attributes to a greater extent. Rheological study of wheat flour blends with germ upto 20%, showed marginal increase in water absorption and over-pressure values. However incorporation of treated wheat germ caused dough weakening in terms of reduction in dough stability and rupture at abscissa values.