Chemical, physical, and sensory changes in rice subjected to UV-C radiation and its acceptability to rice weevil Sitophilus oryzae (L.) (Coleoptera: Curculionidae) and humans

Abstract The objective of this study was to evaluate the effect of ultraviolet C (UV–C) radiation treatment of rice on both the development of S. oryzae and changes in the quality of rice Oryza sativa (L.) (Poales: Poaceae) grains. Husked rice grains were treated with UV-C, and subsequently placed alternately with the control treatment (without UV-C) in an arena. Subsequently, 500 adult S. oryzae were placed in the center of the arena, with free access to both samples for 30 days. On the 30th day of the experiment, a greater number of adult S. oryzae were identified as consuming grains subject to the control treatment; these same S. oryzae also showed greater emergence on the 40th, 50th, and 60th day. In the group treated with UV-C, reduced acidity, protein solubility, K232, K270, luminosity, and damage were observed; however, increases in gravimetric and volumetric yields were also observed. The sensorial analysis of the cooked grains showed that grains treated with UV-C had less acceptance and purchase intention by human panelists, mainly due to the odor attribute. Further studies are still needed to identify metabolites formed in rice subjected to UV-C; however, it is noteworthy that some S. oryzae are able to recognize irradiated rice as distinct from control.