Hr Naik

Effect of Extrusion Conditions and Apricot Powder Incorporation on Colour Parameters of Rice Based Breakfast Snacks

Taking broken rice flour as the base ingredient, apricot powder was used in this study for development of breakfast snacks using twin screw extruder. Response surface methodology using a central composite rotatable design was used to evaluate the effects of independent variables, namely composition (0-40% apricot), barrel temperature (110– 190 oC), screw speed (150–550 rpm) and moisture content (12.5-22.5%) on product colour parameters (L*, a*, b*, chroma, hue angle and ΔE). Multiple regression equations were obtained to describe the effects of each variable on product responses (L*, a*, b*, chroma, hue angle and ΔE). The product responses were most affected by changes in composition, barrel temperature and to a lesser extent by screw speed and moisture content. Increase in temperature and apricot addition decreased luminosity; while increasing redness and yellowness of the extrudates compared to the control (0% apricot).

In-vitro antioxidant and antibacterial activities of pumpkin, quince, muskmelon and bottle gourd seeds

Ethanol and chloroform extracts of pumpkin, quince, muskmelon, and bottle gourd seeds were studied for in-vitro antioxidant and antibacterial activities. Crude protein and fat contents of all the seeds compared favorably with high protein legumes and high oil containing oilseeds. Ethanol and chloroform extracts of bottle gourd seeds had highest phenolic content. A direct positive relationship between antioxidant activities and extract concentration was observed with the relationship being more pronounced in chloroform extract of quince seeds (R2u2009=u20090.9685 and 0.9829) followed by ethanol extract of pumpkin seeds (R2u2009=u20090.9666 and 0.9685) as per 1,1-diphenyl-2-picrylhydrazyl and hydrogen peroxide (H2O2) method, respectively. Seed extracts were also studied for in-vitro antibacterial activity against Salmonella typhii, Enterococcus sp., Escherichia coli, Bacillus subtilis and Staphylococcus aureus. Ethanol extract of pumpkin seeds inhibited the growth of all bacteria; however, both the extracts of quince seeds did not show any activity against S. typhii, E. coli and S. aureus.