The change in the radical-scavenging ability while cooking curry and rice using commercial Roux of different oil and fat contents was examined. The peroxyl radical-scavenging activities in a water-and lipo-soluble environment were measured by the azo compound-cheluminescence methods.   In the lipo-soluble environment, the scavenging activity of Roux with a half content of oils and fats was significantly higher compared that of the standard Roux. Under both environments, the radical-scavenging activity of curry (Roux combined vegetables and meats) using Roux with a half content of oils and fats was higher than that of curry using the standard Roux. We considered that various lipo-soluble spices contained in the Roux with the half content of oils and fats were difficult to extract and not affected by heating. Curry soup using Roux with a half content of oils and fats seems to be a functional cuisine low in calories and having antioxidative ability. We present the assessment system of the antioxidative ability using the same radical and principle of detection in a water- and lipo-soluble environment, which is able to assess the ability of food and meals corresponding to their environment.