Microwave roasting effects on phenolic, tocopherol, fatty acid and phytosterol profiles, physiochemical, oxidative and antioxidant properties of hemp seed oil

Abstract

In the current investigation, the different powers (180, 360, 540, 720, and 900 W) and durations (5 and 10 min) were used for microwave roasting (MwR) of hemp seeds. The influence on yield, oxidative stability, level of phenolic acids, flavonoids, fatty acids, tocopherols, phytosterols, radical scavenging activity (RSA) and physicochemical attributes of hemp oil (HO) upon MwR were investigated. The elevation in MwR conditions had decreased color and peroxide values while increased density, viscosity, p-anisidine value and Maillard reaction products in HO. The phenolic and flavonoid content, RSA, level of catechin, epicatechin, vitexin, myricetin, hydroxybenzoic and hydroxycinnamic acids in HO were highest upon MwR for 10 min at 720 W. The oxidative stability, oil yield, tocopherols and phytosterols exhibited an initial increase followed by decline at elevated conditions of MwR. The MwR (540 W for 5 min) proved effective in improving oil yield and stability, level of phytosterols, phenolic acids, tocopherols, and flavonoids in HO.

Keywords

• Microwave roasting
• Hemp oil
• Tocopherols
• Oxidative stability
• Phenolic acids, Flavonoids
• Phytosterols