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Harvested tomatoes were stored under atmospheres that were normoxic, anoxic, or modified (altered O2 and CO2 concentrations). Each atmosphere was created by storing the tomatoes at 25°C for up to 8 days in different kinds of pouches. During storage, metabolites of the tomatoes were measured using metabolomics. We obtained score plots of the metabolites on eighth day of storage by principal component analysis. There was a tendency for groups to be divided on the basis of score plot according to the composition of each gas. PC1 and PC2 seemed to correspond to the influence of O2 and CO2 concentrations, respectively, and the total contribution rate of the two axes was 72%, so that we concluded that the metabolites were affected mainly by O2 and CO2 concentrations. The results indicate that metabolomics may be an effective tool to reveal the relationship between metabolic state of harvested fruits and the atmosphere.

Concentration of sulforaphane in broccoli is known to be enhanced during storage under an atmosphere of low O 2 (0.002-1.3) and high CO 2 (20.6-25.4). However, maintaining this concentration at a maximum is problematic. Therefore, storage of broccoli florets at low temperatures was investigated. Results showed that storage for 2 days under hypoxia significantly increased (3.3-fold against initial value) sulforaphane concentration. Subsequently, 4 days storage at three temperature levels was conducted. Sulforaphane levels were not maintained at 20 (normal temperature) or 1 (cold temperature). However, after storage at Ϫ20 (frozen) for 4 days, the sulforaphane concentration was not significantly reduced compared with the maximum level on day 2. Meanwhile, this concentration was not significantly higher than those at 20 or 1 on the same day. Storage under hypoxic conditions is known to affect the flavor and taste of vegetables. Therefore, eight taste factors were objectively measured using an electronic tongue. Astringency and bitterness were stable and independent of storage period and temperature, while other tastes were significantly affected by storage period. The rich umami value at Ϫ20 was significantly higher than that at 20 , and in general it was challenging to maintain taste values even for cold or frozen storage.