Several plastic films mixed with porous minerals were developed as packaging use for vegetables and fruits, aiming at elimination of accumulated ethylene in the package. Using several types of these films the effect on keeping quality of some vegetables were investigated comparing with ordinary polyethylene film. In both cases when vegetables were packaged or ethylene only was enclosed, no special ability to eliminate the ethylene was found with the mineral-mixed film bags, while ethylene leaked out gradually in almost the same manner as ordinary polyethylene bag. The gas permeability, however, differed among films suggesting some differences in quality-keeping characteristics.
With shredded cabbage, half-cut cabbage and half-cut lettuce, substantial difference was not found among various films in the effect on keeping freshness. With broccoli, however, the difference of packaging effect was obvious among films. In the films with low gas permeability, green appearance and ascorbic acid content were well kept during storage, but an unfavorable off-flavor occurred with cut-broccoli.

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The simplification and improvement of efficiency and accuracy to control atmosphere were achieved for Modified Air System CA (MASCA) storage, which is hopeful as the economical CA storage system.
In the proposed system (W-Step MASCA), Modified Air with low oxygen content (less than 1%) was flushed to CA storage container in order to succeed rapid pull down of oxygen, and accumulation of carbon dioxide was established subsequently by respiration. For the control of atmosphere within a certain range, oxygen was supplied from air compressor (Step-1) and excess of carbon dioxide was exhausted (Step-2) with modified air which is evolved from generator according to the W-Step program written in Basic and personal computer. The newly developed program eliminated pressure control of air compressor of modified air generator that is time consuming and sometimes resulted in inaccuracy in the former MASCA. W-Step MASCA is energy-saving and supposed to provide an easy way to automatic operation.
The experiments for storage of shiitake-mushroom and peach showed that W-Step MASCA is reliable enough to control atmosphere, and the shelf-life of these fruits and vegetables were prolonged.

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The influence on some food materials to sterilization of ozonated water and on application for the defrosting water in meat processing were investigated.
(1) Concentration of ozonated water decreased immediately in case of existing some saccharides or amino acids. Sterilizating power of ozonated water to each microorganisms decreased in case of existing 1% of casein, starch or skim milk. But it different that species of microorganisms or existing a kind of food materials.
(2) The COD value was decreased slowly, but viable cell count was decreased immediately when the ozone gas supplied continuously to keep 1.5 ppm concentration. E.coli and St.aureus were killed in 20 minutes, B.subtilis was in 40 minutes completely.
(3) Pork meat block and each microorganisms treated with ozonated water on condition that low concentration (0.1, 0.3 ppm) and long time (5 hours). E.coli and St.aureus were killed at 0.1 ppm for 1 hour or 0.3 ppm for 10 minutes. B.subtilis was killed at 0.3 ppm for 50 minutes, but it was not killed at 0.1 ppm for 5 hours completely. Peroxide value in this case showed less than 1.0 after 5 hours. So, it expected that ozonated water was effective way for defrosting in meat processing.

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Salted salmon roes (“Sujiko” in Japanese) were stored at 5 °C for 4 weeks, -3°C for 8 weeks and -18°C for 16 weeks. Then, temporal changes of chemical properties, lipid composition and fatty acid composition of total lipids extracted from various samples were investigated. The results may be summarised as follows total lipids contents in salted salmon roes showed scarcely any changes. However temporal increases of acid value, peroxide value and carbonyl value of total lipids were observed at each storage temperature, while iodine value decreased during storage. Particularly, the above changes in case of storage at -18°C were the smallest in this study, In brief, storage at -18 °C was effective to control for lipid deterioration. Regarding the temporal changes of various lipid contents (g/100g samples) in total lipids, compound lipid fraction content decreased during storage at each temperature, while neutral lipid fraction content increased. Further-more, the temporal decreases of triacylglycerol (major lipid of neutral lipid fraction) content and phosphatidylcholine (major lipid of compound lipid fraction) content were observed during storage, while free fatty acid content clearly increased. The smallest changes were observed at -18°C storage. Regarding the temporal changes of major fatty acid composition of total lipids, neutral and compound lipid fractions, the decrease of highly unsaturated acid contents (wt%) such as 20 : 5, 22 : 6 acids and the increases of saturated acid contents such as 16 : 0, 18 : 0 acids were observed at each storage temperature. And the temporal changes of major fatty acid composition of compound lipid fraction were greater than those of other lipid fractions. Furthermore, these tendencies were the least conspicuous in case of storage at -18°C.

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