APPLICABILITY OF VISCOSITY MEASURING METHOD TO THE DETECTION OF IRRADIATED SPICES

The conditions for measuring viscosity of spices to detect radiation t reatment and the applicability of the method to various spices were in vestigated. Viscosities of black and white peppers, ginger and turmeri c decreased depending upon dose, when they were measured after heat ge latinization at pH12. However, the viscosities of cinnamon and nutmeg did not show a dose dependent relation. The viscosity of irradiated on ion powder was lower than that of unirradiated sample, when determined at pH5 without any heat treatment. A normalized viscosity parameter, viscosity/starch content (mPa.s/g of starch), resulted in a.most const ant values for unirradiated black and white peppers, irrespective of t he harvesting locality. The results in this study suggest that irradia ted black and white peppers can be detected by viscosity measurement w ithout any information about the harvesting locality.