Quality of Alfalfa Sprouts Grown from Irradiated Seeds
Authors Fan, Xuetong; Rajkowski, Kathleen; Thayer, Donald
Submitted to: Journal Of Food Quality
Publication Acceptance Date: May 5, 2002
Publication Date: May 5, 2002
Interpretive Summary: Outbreaks of foodborne illness have been associated with consumption of seed sprouts. This has been due to the presence of a large number of human pathogens in sprouts grown from contaminated seeds. Irradiation effectively inactivated foodborne pathogens in contaminated seeds. The FDA has approved the use of ionizing radiation to control microbial pathogens in seeds for sprouting. However, the nutritional value of alfalfa sprouts from irradiated seeds is not clear. This study was conducted to investigate contents of vitamin C, total antioxidant, carotenoid, and chlorophyll of sprouts grown from irradiated seeds as a function of radiation dose and storage. Our results showed that sprouts grown from irradiated seeds had higher vitamin C and total antioxidant contents compared to those grown from seeds that were not irradiated. The effect was greater at higher radiation doses. The higher nutritional value of alfalfa sprouts was also observed after 21 days storage at 7C. Irradiation had no effect on carotenoid or chlorophyll content. This information is useful for sprout growers.
Technical Abstract: Sprouts grown from non-irradiated alfalfa seeds and those irradiated at 1, 2, and 3 kGy were stored at 7C for 21 days. Sprout quality was measured initially and after 21 days storage. Sprouts grown from irradiated seeds had an increased vitamin C content and antioxidant activity measured by the ferric reducing antioxidant power (FRAP) assay both initially and after 21 days. The elevation in vitamin C content and antioxidant activity was greater with increasing radiation dose. The vitamin C, chlorophyll and carotenoid contents as well as antioxidant activity all decreased during storage. Levels of chlorophyll and carotenoid were similar in sprouts grown from irradiated and non-irradiated seeds both initially and after storage.