Abstract Chinese yam (Rhizoma Dioscoreas Oppositae) has been recorded in Traditional Chinese Medicine and is utilized as a common food delicacy in China. This study was carried out to evaluate effects of superfine grinding at variable mesh sizes on physicochemical, thermal, microstructural attributes, bioactive compounds and radical scavenging activities (RSA’s) of yam flour powders (YFP). Physical, color, hydration, total phenolic, flavonoid contents, RSA’s and absorption characteristics were significantly influenced by exhibiting increasing trends with reduction of YFP particle sizes. YFP fraction obtained at M400 size showed obviously improved specific surface area as compared to M60 fraction. Generally, it may be implied from the results that free-form phenolic compounds exhibited increasing trends whereas cell-wall bound phenolic compounds showed particle size-dependent decreases with corresponding increases in mesh size. ESEM micrographs endorsed the finding of reduction of YFP particle sizes with corresponding increases in sieve mesh sizes. ESEM analysis evidently showed that mechanical shear significantly led to enhancement of surface area. Differential scanning calorimetry showed that melting temperature of YFP with reduced particle size were lower. Conclusively, it may be implied that YFP superfine powders might be utilized in food formulations with improved functional properties and uniformity.

Abstract Highly nutritional and functional properties of chia seeds would make it unique than other grains. Considering its known properties chia can be used as an important food ingredient. These are rich in fiber, ash, protein, polyunsaturated fatty acids (PUFA) and antioxidants. Higher proportion of protein having greater biological value with essential amino acids and high dietary fiber content prevents several metabolic disorders and obesity. It is also consist of PUFA helpful in lowering cardiovascular diseases. Rusks were supplemented with chia flour at a rate ranging 5 to 20% with the goal to modify the fiber content, nutritional contents and physicochemical properties. The obtained results were highly significant and showed increasing trend in dietary fiber and PUFA values. Texture values decreased significantly. Sensory evaluation showed significant (p<0.05) differences in color, flavor, texture and overall acceptability. Most acceptable treatment was with 5% chia flour supplementation with a mean score of 8.10. Hence, Chia flour-supplemented rusks up to 5% addition level could be utilized as a convenience food and vehicle of improved nutritional status with health beneficial bioactive compounds. Moreover, supplementation of chia flour led to improvement of functional properties of wheat rusks as a valuable source of dietary fiber and bioactive compounds.