Effect of Pre-Treatment on Drying of Red Amaranth and its Utilization in Noodles Preparation

Abstract

Red amaranth is a perishable, colored leafy vegetable that can be preserved through a variety of methods, including dehydration. The current study was conducted to investigate the effect of pre-treatments (blanching, sulphitation, and blanching plus sulphitation) and drying methods (cabinet and solar) on drying rate and color intensity of red amaranth (leaves and stems) and the development of red amaranth enriched noodles. Drying rate and color intensity were varied in different degrees based on applied pre-treatment and drying method. For drying of red amaranth leaves, blanching plus sulphitation followed by cabinet drying showed highest drying rate (0.67 h-1), whereas blanching followed by cabinet drying showed fastest drying rate (0.69 h-1) for red amaranth stems. Color absorbance study revealed that sulphitation pre-treatment and cabinet drying leads highest color absorbance (0.261) in red amaranth leaves, while blanching and cabinet drying provides highest color intensity (0.121) in stems. The use of red amaranth leaves powder in noodles preparation at 5% and 10% wheat flour substitutions gave significantly different (p<0.05) sensory parameters. Substitution of 5% wheat flour by sulphited and cabinet dried red amaranth leaves powder gave the highest overall acceptability of developed noodles.