Abstract
The vegetables that the consumers purchase from stores and take in every day are diverse depending on the origin and growing conditions. However, we have only a single set of numerical values designated in the standard tables of food composition in Japan when we calculate nutrient of meal or food ingredients. The standard food compositions are to be the average of the nutrient of food that is marketed throughout the year, although some vegetables often contain high nutrients in the peak season while they have low values in the off-season. The climate of Japan might affect the difference of the values because the islands of Japan lie long north and south. In this study, we investigated 6 samples of vegetables (cabbage, Japanese radish, tomato, leek, spinach, sweet potato) that were sold in 6 supermarkets in Japan from 1999 to 2003, and analyzed the relation of the food compositions and the roots of products every other month. 1) The sales area and the producing area of the supermarket-sold vegetables tended to be close or same except in summer and winter season. 2) We found clear seasonal changes of the contents in the following samples; vitamin C of tomatoes was high in summer, vitamin C of leeks was low in summer, water of spinaches was high in summer, and carotene, vitamin C and sugar contents of spinaches were low in summer.
