Impact of Gamma irradiation pretreatment on the characteristics of native and defatted date palm seed flour and oil

Abstract

Numerous beneficial compounds in date seeds are less accessible due to natural barriers. These compounds can be especially beneficial to human health when linked to their excellent antioxidant capacity. The aim of this study is to elucidate the effect of gamma irradiation on releasing these compounds in order to enhance the chemical composition of native and defatted date seed powder. To achieve this, date seed flour was exposed to two doses of gamma irradiation (1 and 5 kGy), and then the irradiated samples were assessed for their chemical properties. Additionally, after irradiation pretreatment, oil extraction was carried out using different solvents, and the native and defatted date seed flours were analyzed. The results showed that gamma irradiation had a significant effect on the color and chemical composition of the date seed powder. The solubility of amino acids in solvents was affected by gamma irradiation, resulting in defatted seed flours that were richer in some amino acids. Furthermore, irradiated-defatted seed powder exhibited higher levels of neutral sugars and esterified phenols, which contribute to a better antioxidant capacity. FTIR spectra confirmed that, after irradiation, there was a breakdown of the cell wall structure, allowing for a higher oil yield with more effective antimicrobial activities. In conclusion, irradiation pretreatment allowed the native and defatted date seed flour to gain additional benefits by making chemical compounds more extractable.