The effect of irradiation (dose levels of 0, 2.5, 5, 10 and 20 kGy) on nutritive (amino acids, and protein digestibility) and anti–nutritional characteristics [total phenols (PH), tannins (TA), phytic acids (PA) and oxalate (OX)], level of anti–nutrients in vitro digestibility (IVPD) and protein digestibilty corrected amino acid score (PDCAAS) of sorrel seeds (Hibiscus sabdariffa), were examined. The results showed that amino acids content were significantly (p < 0.05) enhanced by the irradiation up to the dose of 10 kGy in comparison with the control sample. Radiation processing significantly (p < 0.05) reduced the levels of total phenols, tannins, phytic acids and oxalate. IVPD and PDCAAS were significantly enhanced in a dose– dependent manner, relative to unirradiated control sample. The data sets for each dose level exhibited high correlation coefficient between dose and PH, TN, PA, OX and IVPD. We conclude that the overall dose of 10 kGy is very effective for hygienation and quarantine purposes and does not adversely affect the nutritional quality of sorrel seeds.
Keywords: irradiation, amino acids, sorrel seeds, in vitro protein digestibility, IVPD, anti–nutrients, Hibscus sabdariffa, Roselle, nutritive characteristics, anti–nutritional characteristics, phenols, tannins, phytic acids, oxalate, radiation processing, unirradiated samples, hygienation, quarantine, nutritional quality, dosage, dose–dependency, Kano, Nigeria, postharvest technology, innovation