Effect of incorporation of nano encapsulated curcumin on the product quality of instant rice and extrudates from brown top millets: retention and stability studies

Curcumin, a bioactive compound known for its antioxidant and anti-inflammatory properties, has limited bioavailability
due to poor solubility and rapid degradation during processing. With the growing demand for functional foods that are
convenient and nutritionally enhanced, incorporating curcumin in staple-based value-added products can offer significant
health benefits. The study aims to develop value-added products, quick-cooking rice (QCR) and millet extrudate, by incor-
porating nano encapsulated curcumin (NEC). The quick-cooking rice was processed by steam cooking and fluidized drying
followed by rehydration. Two formulations of NEC incorporated fluidized dried Bioactive quick cooking rice (BQCR-1 and
BQCR-2) and Rehydrated Bioactive quick cooking rice (RBQCR-1 and RBQCR-2) were compared with their quick cooking
rice control and rehydrated quick cooking rice control (QCR-C and RQCR-C) for their physico-chemical properties. The
BQCR- 2 (6.6 mg/100 g) exhibited the highest curcumin retention. RBQCR-2 also showed the highest curcumin content
with a concentration of 5 mg/ 100 g. Bio-accessibility testing revealed that sample BQCR-2 exhibited the highest release
percentage. The subsequent objective was to explore bioactive-incorporated value-added products using brown top millet
and to study the effect of extrusion on the retention of NEC. The flour was processed for brown top millet, maize, and rice,
and three combinations were formulated with varying proportions. The flour with the initial NEC concentration showed
the highest curcumin content (9.92/5.96 mg/100 g) before and after extrusion. The unique processing methods employed in
this study offer a promising approach for enhancing the bioavailability and retention of curcumin in these products, which
can have significant implications for their industrial applications in the future. Although the extrusion process led to some
degradation of curcumin content, it still retained a substantial amount of the bioactive compound.