The effects of combinations of bi-axial polypropylene (OPP) film bags and shipping containers on the quality stability of Welsh onion (Allim fistulosum L.) were investigated under simulated or actual conditions. When the Welsh onion was stored at a low temperature with high carbon dioxide and low oxygen levels, the respiration rate was reduced, indicating an extension of shelf life. In actual transportation, there was only a small difference in the Welsh onion temperature between a foamed polystyrene container and the usual corrugated fiberboard container. The result suggests that both materials have almost the same holding temperature effect. In a simulated condition where the Welsh onion was sealed with roughly heat-sealed OPP film bags and then stored in the foamed polystyrene containers at 20°C, the carbon dioxide level increased while the oxygen level decreased because of the high gas-barrier ability of the foamed polystyrene. Moreover, the carbon dioxide and oxygen levels were suppressed at 8.8 to 10.1% or 2.6 to 3.4%, respectively, by using completely heat-sealed OPP film bags and ordinary corrugated fiberboard containers. These results indicate that both materials provide the optimal storage condition for Welsh onions.

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To investigate the multiplication of soft-rot bacteria during the processing and storage of 'Asazuke' of Chinese cabbage, the bacteria transformed with plasmid pBR325 to acquire a resistance to three antibiotics, were used for quantification based on both antibiotic resistance and growth on selective medium. The soft-rot bacteria readily multiplied in the 2 xTY medium modified with a concentration of 2-3 % NaCl, in which 'Asazuke' of Chinese cabbage was usually prepared. When the medium with a pH of less than pH 4.5 was used, soft-rot bacteria could not multiply although they multiplied in a medium with a pH of more than 6.0. The pathogenicity of the transformed bacteria to Chinese cabbage was similar to that of the non-transformations. The addition of the antibiotics to the medium suppressed almost completely the formation of colonies of the leaf surface bacteria prepared from healthy Chinese cabbage. The use of a modified crystalviolet-pectate medium combined with antibiotic resistance was more suitable for the suppression of the multiplication of the leaf surface bacteria, suggesting that the transformed bacteria could be quantitatively assayed under contaminants. During the storage of 'Asazuke' of Chinese cabbage at 5°C, the concentration of the soft-rot bacteria in the soaked fluid for 'Asazuke' did not change for 15 days. However, upon storage at 10°C, the bacteria multiplied gradually, and the pH of the solutions decreased along with the appearance of turbidity.

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Cabbage (Brassica oleracea L. var. capitata L.) is one of the most popular vegetables produced in large quantities in Taiwan. Because the harvest of this vegetable is so concentrated in winter time, its surplus always brings about a big financial loss to farmers. On the contrary, the shortage of vegetables in the rainy seasons from spring through summer, often creates a problem in vegetable supply. Thus, how to process and preserve the vegetables harvested in winter and store them for supply in necessity during rainy season is a major agriculture and food the industry problem in Taiwan.
The purpose of this study in to develop a technique to process cabbage minimally so that it can keep good quality comparable to fresh produce after being stored for at least 3 months. For this purpose the half cut cabbages were treated with a solution of 7.0% salt and 0.236% acetic acid under a vacuum of 76 cm-Hg for 23min, then, vacuum packed, pasteurized at 85°C for 20min and stored at 5°C or-18°C. The quality (pH, total acidity, vitamin C, lightness, redness, yellowness, total plate count, Lactobacilli) of cabbages stored for 4 months were found to be similar to that of the fresh material.

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The deterioration and respiratory rate of carrot sections were measured to determine the effect of the ratio of vertical-or transverse-cut surface of sections. The small sections were more perishable than the large ones, the deterioration rate of sections of xylem was faster than that of phloem, and the sections having a high ratio of vertical area to the transverse decayed more rapidly than the low ones. The respiratory rate, O₂ uptake and CO₂ production, of phloem was lower than that of xylem, and the rise in respiratory rate of the sections having a high ratio of vertical area to the transverse was faster than that of low ones after decay. The difference of tissue or ratio of vertical or transverse area affected the respiratory rate and induced a difference in deterioration rate.

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