Abstract This study was aimed at optimization of potato starch gel preparation process by response surface methodology and various process parameters were optimized for textural, gelation and sensory properties. 3D response surface and contour plots showed that independent variables, such as extraction time, extraction temperature and potato starch concentration significantly affected (p < 0.05) texture of potato starch gel. It was observed from RSM analysis that target responses regarding texture characteristics (hardness 1, hardness 2, springiness and chewiness) were significantly reliant on potato starch conc. followed by extraction time and temperature. To was found in range from 102.98 to 109.87 °C whereas, the mean To was maintained at 107.20 °C. It was evident from data of experimental runs that To showed relatively consistent tendency in majority of samples while, experimental runs no. 4 and 5 exhibited a maxima and minima of 109.87 °C and 102.98 °C, respectively. It was evident from To value that starch granules were subjected to degree of disintegration in its internal granules structure, and this disintegration led to polysaccharides release in surrounding medium.

Abstract Calcium fortification is usually achieved by employing wheat flour as the most frequently used vehicle. In this study, potential of calcium extraction from chicken eggshell and its utilization as a bread fortificant in straight grade flour (SGF) is investigated. In addition, the fortified and unfortified (control) flour samples were evaluated for nutrient composition and rheological properties. Results showed that addition of fortificant at different concentrations significantly (p<0.05) enhanced calcium content of fortified flour and it was considerably increased from 115.80 mg/kg (To) to 1135.1 mg/kg (T3). Nutrient composition data of fortified flour have shown a significant (p<0.05) reduction in moisture content of flour from 12.7% (To) to 11.76% (T3) and protein content from 9.89% (To) to 9.79% (T3). However, a significant increase in ash content was observed by increasing fortificant level from 0.54% (To) to 1.04% (T3). Rheological properties indicated a significant increase in water absorption from 63.60 to 67.527%, dough development time (DDT) from 7.38 to 11.37 min and dough stability from 13.79 to 17.37 min. Textural characteristics of fortified bread revealed a significant reduction for hardness values from 11.40 N (control) to 6.50 N (T3) in response to fortificant addition. Quality assessment of bread indicated that bread quality was significantly affected with corresponding rises in fortificant addition levels.