Dietary supplementation of black cumin (Nigella sativa) meal in the formulation of protein‐enriched cookies, further in vivo evaluation of protein quality with physicochemical and organoleptic characterization

Nigella sativa has solid historical importance as a medicinal herb and is widely used in the bakery industry. The study revealed that the defatted black cumin meal (DBCM) possesses a high nutritious composition and amino acid profile, such as Leu, Lys, Arg, Phe, and Glu. The supplementation effect of wheat flour with defatted black cumin meal (DBCM) at levels of 5%–25% was explored on the cookies' nutritional, functional, and organoleptic attributes. Moreover, the present work was conducted to assess the in vivo protein quality of defatted black cumin meal (DBCM)‐supplemented cookies using the albino rat's experimental modeling for 10 days. Rheological characterization suggested a solid elastic behavior for all cookies dough with elevation in G' (138,652–230,926 Pa), G" (34201–45,092 Pa), and G* values due to protein addition. The functional characteristics of the flour blends showed that DBCM addition significantly (p ≤ .05) improved oil (70.56%–165%) and water (84.83%–232.67%) absorption capacities, emulsion, and foaming stability. The physicochemical and organoleptic assessment of the cookies exposed that a 20% level of substitution of DBCM produced acceptable cookies. The net protein utilization (NPU), protein efficiency ratio (PER), true digestibility (TD), and biological value (BV) significantly differ from each other among all the supplementation diet groups with 0%–25% DBCM. Nigella sativa, with its rich historical significance as a medicinal herb, plays a crucial role in the bakery industry. This study investigated the impact of supplementing wheat flour with defatted black cumin meal (DBCM) at varying levels (5%–25%) on the nutritional, functional, and sensory characteristics of cookies. The physicochemical and organoleptic evaluations of the cookies revealed that a 20% substitution of DBCM resulted in cookies that met acceptable standards. The supplementation levels (0%–25% DBCM) exhibited significant differences in net protein utilization (NPU), protein efficiency ratio (PER), true digestibility (TD), and biological value (BV) among the various diet groups.