Applicability of near infrared spectroscopy for detecting post-fumigated weevils in packaged rice

Abstract

This research proposes the utilisation of Fourier transform near infrared spectroscopy to estimate post-fumigation rice weevils in packaged rice. Different mixtures of dead rice weevils in rice samples were scanned via Fourier transform near infrared through the package, and then the data were statistically analysed. The rice samples were of milled hom mali rice and brown hom mali rice, while the packaging materials were polyethylene plastic bags, polypropylene woven plastic sacks and hemp sacks. The results revealed that Fourier transform near infrared is most applicable for detecting dead rice weevils in milled hom mali rice in polyethylene bags as indicated respectively by validation r2 and RPD values of 0.93 and 3.92, followed by the milled hom mali rice-polypropylene case with r2 and RPD values of 0.87 and 3.05. The r2 and RPD values were 0.86 and 3.00 for brown hom mali rice-polyethylene and 0.75 and 2.04 for brown hom mali rice-polypropylene. Due to poor penetration of NIR light through the hemp sacks, experiments were not carried out for this packaging material type.