The potential of near infrared (NIR) reflectance spectroscopy for non-destructively probing structural changes in protein during the process of denaturation was investigated. Lysozyme as a model protein was adjusted to 15% moisture content, placed in a steel cylinder and then heated at 30, 90, 120 and 150ºC under pressure conditions of 10, 15, 30 and 45 MPa. Significant changes were observed in absorption bands near 2144, 2168 and 2208 nm with increases in temperature and pressure. The spectral changes were, in general, much larger for samples subjected to both high temperature and pressure than for those subjected to high temperature only. It is likely that these changes are due to changes in the secondary structure of protein. Absorbance changes at the above wavelengths showed high correlations to variations in solubility and digestibility of protein treated under high heat and pressure conditions. The results of multiple linear regression analysis suggest that NIR spectroscopy may be used to predict the solubility and digestibility of protein.

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.