Characteristics and nutritional value of biscuits fortified with debittered salmon ( Salmo salar ) frame hydrolysate

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

BACKGROUND

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.

RESULTS

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).

CONCLUSION

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.

Assessing the Enzymatic Hydrolysis of Salmon Frame Proteins through Different By-Product/Water Ratios and pH Regimes

The enzymatic hydrolysis of fish by-product proteins is traditionally carried out by mixing ground by-products with water. In addition, pH control is used to avoid pH drops. Higher costs are involved due to the use of pH control systems and the consequent energy cost in the drying stage. This work aimed to evaluate the effect of these conditions on the hydrolysis of salmon frame (SF) proteins, including the SF hydrolysis without added water. SF hydrolysis by subtilisin at 50, 75, and 100% SF under different pH regimes were evaluated by released α-amino (α-NH) groups, total nitrogen, degree of hydrolysis, and estimated peptide chain length (PCL) at 55 °C. The concentration of released α-NH groups was higher in the conditions with less added water. However, the nitrogen recovery decreased from 50 to 24% at 50 and 100% SF, respectively. Changing the SF/water ratio had a more significant effect than changing the pH regime. Estimated PCL changed from 5-7 to 7-9 at 50 and 100% SF, respectively. The operating conditions affected the hydrolysis performance and the molecular characteristics of the hydrolysate.