Identification of Rice Variety Using near Infrared Spectroscopy

Abstract

Current techniques for the discrimination of varieties of rice is known not to be objective because of having to depend on the naked eye of a well trained inspector. DNA fingerprint methods, based on the genetic character of rice, has been shown to be inappropriate for on-site application because the method needs a lot of labour and skilled expertise. In order to solve these problems, many researchers have tried to develop a non-destructive method which possesses speed and functionality for the inspection centre of the government. Rice consumers want tot confirm cultivation origin and its variety because they believe price or eating score has a high correlation according to them. Sometimes illegal utilisation of rice has been reported and the variety name has been mismatched with the actual rice variety due to the non-establishment of objective techniques for discrimination of rice origin and variety. On the basis of this situation, we investigated the possibility of developing a non-destructive discriminant method for the domestic rice variety in this research. At the 8th IDRC held at Chambersburg in 1996 we reported that an image processing technique using a CCD camera could discriminate the variety of rice with high accuracy in the case of quite different shaped rice but the accuracy reached 90% for similarly shaped rice. At the prsent conference, near infrared spectroscopy, which can offer internal characters of a single rice kernel, giving useful information for identifying rice variety, was introduced. We have developed several tools for measuing the NIR spectra of whole, polished rice. The spectra using a single grain cell with grinding facilities was more effective than the others in accuracy of identification after principal component analysis. In conclusion, near infrared spectroscopy can be used to identify rice varieties even though even though accuracy of identification needs to be improved.