Characterization of rusk incorporated with black rice (Oryza sativa L.) for its physicochemical and functional properties, in-vitro starch digestibility, and anti-inflammatory efficacy.

Abstract

The consumption of bakery goods is gradually increasing due to their accessibility, convenience, distinctive flavor, and affordability. The food industry is experimenting with novel methods of fortification, supplementation, enrichment, and adding value to bakery ingredients. The present investigation assessed the physicochemical, morphological, and sensorial properties, and anti-inflammatory efficacy of rusks with black rice incorporated. The addition of black rice flour significantly increased (P < 0.05) the total ash (from 1.34 to 1.78 g·kg-1 ), crude protein (from 5.68 to 75 g·kg-1 ), and total fat (from 11.93 to 12.80 g·kg-1 ) content but the carbohydrate content of the rusk decreased significantly (from 76.23 to 71.42 g·kg-1 ). Similarly, the phenolic and flavonoid content increased and showed excellent free-radical scavenging activity after black rice incorporation. The inclusion of black rice flour led to improved functional properties while decreasing the rate of starch digestion and the eGlycemic Index (eGI) score. The sensory scores declined after black rice incorporation but for all rusk samples acceptability was above the lowest level (i.e., ≥5). This study demonstrated that the incorporation of black rice flour into refined wheat flour can enhance the nutritional value of rusk and that it is possible to prepare rusk and other bakery goods using up to 30% black rice with taste and other sensory attributes similar to control rusk. © 2023 Society of Chemical Industry.