This study investigated protein, amino acid, fatty acid composition, in vitro starch and protein digestibility, and phenolic and antioxidant composition of bread fortified with salmon fish (Oncorhynchus tschawytscha) powder (SFP). The proximate composition in control and SFP breads ranged between (34.00 ± 0.55⁻31.42 ± 0.73%) moisture, (13.91 ± 0.19⁻20.04 ± 0.10%) protein, (3.86 ± 0.02⁻9.13 ± 0.02%) fat, (2.13 ± 0.02⁻2.42 ± 0.09%) ash, (80.10 ± 0.018⁻68.42 ± 0.11%) carbohydrate, and (410.8 ± 0.18⁻435.96 ± 0.36 kcal) energy. The essential amino acids of the control and SFP breads ranged between 261.75 ± 9.23 and 306.96 ± 6.76 mg/g protein, which satisfies the score recommended by FAO/WHO/UNU (2007). Protein digestibility of the products was assessed using an in vitro assay. The protein digestibility, comma, amino acid score, essential amino acid index, biological value, and nutritional index ranged between 79.96 ± 0.65⁻80.80 ± 0.99%, 0.15 ± 0.06⁻0.42 ± 0.06%, 62.51 ± 1.15⁻76.68 ± 1.40%, 56.44 ± 1.05⁻71.68 ± 1.10%, 8.69 ± 0.10⁻15.36 ± 0.21%, respectively. Control and SFP breads contained 60.31 ± 0.21⁻43.60 ± 0.35 g/100 g total fatty acids (saturated fatty acids) and 13.51 ± 0.10⁻17.00 ± 0.09 g/100 g total fatty acids (polyunsaturated fatty acids), and SFP breads fulfil the ω-6/ω-3 score recommended by food authority. There was a significant effect of SFP on bread-specific volume, crumb color, and textural properties. The in vitro starch digestibility results illustrate that the incorporation of SFP into wheat bread decreased the potential glycemic response of bread and increased the antioxidant capacity of bread. In conclusion, this nutrient-rich SFP bread has the potential to be a technological alternative for the food industry.
Keywords: antioxidant activity; bread; fatty acids; in vitro protein digestibility; in vitro starch digestibility; protein; salmon powder.