A modified air generator was developed by improving nitrogen generator which is based on PSA (pressure swing adsorption). The modified air generator is able to produce the modified air which contains various concentration of oxygen from 0.1 to 20% by control the pressure of the air compressor. The modified air generator was useful to pull down the oxygen concentration of the atmosphere of fruits and vegetables rapidly, and was helpful to remove excess of carbon dioxide accumulated by respiration without affection of oxygen atmosphere. These results suggested that the modified air generator is applicable to control the atmosphere of fruits and vegetables. The gaseous environment in the storage chamber was analyzed routinely with gas chromatography, and the estimation of nitrogen, oxygen and carbon dioxide concentration was carried out by a computer program presented in this study.

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The modified air generator which is based on the improved PSA (pressure swing adsorption) nitrogen generator is designed to produce modified air of any concentration of oxygen between 0.1 and 20% from the air. Modified Air System CA (MASCA) storage which is composed of the modified air generator, storage chamber and personal computer was developed for the preservation of fruits and vegetables. A program was developed to control the atmosphere within the certain range which is known as Controlled Atmosphere storage. The optimum oxygen concentration and the amount of the modified air to provide for the fruits and vegetables were calculated with the program written in BASIC. MASCA storage was applied to preserve shiitake-mushroom, strawberry and broccoli. The atmosphere was well maintained through the experiments within the desirable range depending on the samples. MASCA storage prolonged the storage period of these vegetables at least twice as much as conventional refrigeration.

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Near infrared (NIR) spectroscopy is becoming a common method in food analysis, because it is very rapid, and little or no sample preparation is required. However there are few softwares for vegetable and fruit analyses, now.
Therefore, softwares for non-destructive quality evaluation of tomato were investigated with NIR spectroscopy.
(1) Regression analyses between data from NIR spectrum and chemical analyses were executed. Wavelengths and calibrations which were highly correlative with contents of tomato, were searched by multiple linear regression.
(2) Wavelengths and calibrations which were highly correlative with taste examination values of tomato, were searched by multiple linear regression, too. The correlation coefficient was r =0.78.
(3) Confidences of searched calibrations were examined with unknown sample.
With the mean of applying NIR to surface of tomato, it was maked clear that calibrations of contents and taste in tomato were confidential. That is to say, correlation coefficients with Brix, Acid, L-sugar, K, Mg, and grocery were r= 0.89, 0.56, 0.68, 0.91, 0.91 and 0.72 respectively.
The correlation coefficient of taste was r =0.89. All these correlations were found to be significant.
(4) From the above mentioned facts it was confirmed that we could get effective calibrations for non-destructive quality evaluation of tomato with NIR spectroscopy.

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Changes of chlorophyll derivatives in stored parsley (Petroselium sativum HOFFM., cv Paramount) and mitsuba (Cryptotaenia Japonica HASSK., cv Osaka-mitsuba) leaves were studied in order to clarify the mechanism of chlorophyll degradation.
The chlorophylls and their derivatives (pheophytins, chlorophyllides and pheophorbides) were isolated by using thin layer chromatography, and identified by measuring Rf values, visible colors and spectral characteristics. This method is considered to be suitable for the separation of chlorophylls and their derivatives.
Chlorophylls and pheophytin a contents decreased with the progress of yellowing of parsley and mitsuba leaves stored at 25°C, but the shifts of absorption spectrum were not observed. In parsley leaves stored at 25°C, small amounts of pheophorbide a and chlorophyllide a were detected, but these contents did not increase with yellowing of leaves. In case of mitsuba leaves, small amounts of chlorophyllide a and pheophorbide a were detected in the fresh leaves, but these contents also did not show any increase with yellowing of leaves.
It is concluded from these results that most of the chlorophylls in stored parsley and mitsuba leaves are degraded directly to the colorless products with the opening of porphyrin.

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