Utilisation of concentrated whey in the production of multigrain bread: optimisation of solid levels in concentrated whey and temperatures of baking

An attempt was made to utilise paneer whey, a major by-product of the dairy industry, as a diluent in the production of multigrain bread. The paneer whey, having a TS content of about 6%, was concentrated to three levels: 15, 20 and 25% TS, and was used to fully replace water in the dough formulation containing wheat flour supplemented with 5% each of sorghum, oats, flaxseed and maize flour; 3% yeast, 2% salt, 10% sugar and 15% oil (all on flour basis). The dough samples made by incorporating the different levels of whey were baked at three different temperatures: 160, 185 and 210°C, and the effect of the incorporation of whey as well as the baking temperatures on the sensory and textural attributes and crust colour of the bread was studied in a single experimental model. Based on the overall acceptability scores it was observed that the use of 15%TS whey as diluent resulted in multigrain bread with the highest acceptability. The rheological studies indicated increasing trends in hardness and SRT and decreasing trends in cohesiveness and springiness with increasing TS whey. The crust colour, measured by reflectance values, indicated an increase in darkness with increasing TS whey and baking temperature. The mean overall acceptability scores indicated that 185°C was the best baking temperature. The hardness of the bread increased with increasing baking temperature, and the springiness was maximum at 185°C. Therefore, it was henceforth recommended to use concentrated whey having 15%TS as diluent in the dough of multigrain bread and 185°C baking temperature.