The bacterial ethylene absorbent (BEA), isolated from soil and packed in plastic film (NF sheet), were used for sudachi fruit (Citrus sudachi hort. ex Shirai) and some vegetables to keep their qualities during storage at 25°C.
The decrease of oxygen and increase of carbon dioxide concentrations in polyethylene film (PE, 0.05mm thickness) package containing sudachi fruits were not affected by BEA and/or ethylene treatment at initial concentration of 50ppm. Applied ethylene in package disappeared by diffusing through PE film and being absorbed by BEA within 3 days. The yellowing of fruits peel was promoted by ethylene treatment and BEA retarded the yellowing of both treated and non-ethylene treated fruits. The titratable acidity and pH did not show any change with ethylene treatment and/ or addition of BEA during 10 days storage.
The concentration of oxygen increased and concentration of carbon dioxide in polyethylene film (PE, 0.05mm thickness) package containing vegetables used, and they were not affected by BEA and/ ethylene treatment at initial concentration of 50 ppm. Applied ethylene in package disappeared by diffusing through PE an being absorbed by BEA within 2 days. BEA retarded the wilting and fading of petal of perilla (Perilla ocymoides L.) spike, yellowing of parsley (Petroselinum crispum C. O.) leaf, abscission of leaflet of Japanese pepper (Zanthoxylum piperitum DC.) leaf, and abscission of calyx in eggplant (Solanum melongena L.) fruit. BEA did not retarded the decay of perilla seedling, water pepper (Polygonum hydropiper L.) seedling, and flower of mioga ginger (Zingiber mioga Rosc.). The yellowing of asatsuki (Allium schoenoprasum L.) leaf and browning of chrysanthemum (Chrysanthemum morifolium Ramat.) flower were not retarded by BEA, and leaf of perilla did not show change during 5 days storage.

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Broccoli (Brassica oleracea L., Italica Group) was stored in the automatic Modified Air System CA (MASCA) storage chamber in order to assess the effect on the retention of broccoli quality and function of the auto-MASCA apparatus.
1) The auto-MASCA apparatus worked as designed and the atmosphere in the CA chamber was well controlled within the range between 2 and 4% for oxygen and 4 and 6% for carbon dioxide, respectively. 2) After 1 day storage, the rate of respiration of broccoli was reduced by approximately 1/2. The rate had decreased by 70% after 2 days of storage. 3) Color, chlorophyll and ascorbic acid content were retained better in broccoli stored under MASCA than in air. 4) The changes of amino acids were retarded by MASCA. 5) Undesirable odors and taste were not developed in the samples of MASCA storage.
The results obtained suggest that auto-MASCA is reliable as a CA storage facility.

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The cause of rapid softening occurred in Japanese persimmon 'Saijo' fruits after removal of astringency by dryice (CO₂ gas from dryice) and also the possibility of long-term storage of the fruits by the combination of low temperature, polyethylene (PE) bag and ethylene absorbent were investigated.
The peak value of ethylene production which occurred after the dryice treatment was 2.2μl/kg· hr in 'Saijo', which was 10 times higher than that in 'Hiratanenashi'. These tests were conducted at 20°C.
The peak value of ethylene production in 'Saijo' fruits either treated with CO₂ gas or treated with dryice and packed with ethylene absorbent was about 1/10 of that in those treated with dryice and packed without ethylene absorbent. The fruits treated with CO₂ gas softened 2 days later and those treated with dryice and packed with ethylene absorbent did 10-15 days later than those treated with dryice and packed without ethylene absorbent. These tests were also conducted at 20°C.
The long-term storage tests were conducted in 2 years. In the first year, the fruits were harvested about 10 days later than a proper time and stored at lt in 0.05mm PE bag with ethylene absorbent after the treatment of dryice or CO₂ gas. The storage life with proper hardness of the fruits treated with dryice was 37 days, whereas that of those treated with CO₂ gas was 46 days. The apical parts of the fruits treated with dryice softened 10 days earlier than those treated with CO₂ gas. In the second year, the fruits were harvested at the proper time and stored at 2°C in 0.06 or 0.08mm PE bag with or without ethylene absorbent after the treatment of dryice or CO₂ gas. The storage life with proper hardness of the fruits packed with ethylene absorbent was 85 days, which was 13 days longer than that without ethylene absorbent. Ethanol contents in fruits increased linearly during the full period of storage, and acetaldehyde contents in fruits increased rapidly from 48 days after the start of storage. In both years, internal browning appeared in the flesh adjacent to calyx limitedly in the fruits treated with dryice.

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This study was carried out to investigate incidences of halotolerant and halophilic histamine-forming bacteria which grew in broth containing 12 percent sodium chloride in the commercial marine fish. These two groups of bacteria were called HH bacteria in this paper. The incidence was almost 30 percent. Fifty-seven percent of HH bacteria isolated from the fish were Gram positive cocci and identical with genera Staphylococcus and Micrococcus. Vibrio was dominant genus in Gram negative HH bacteria. Staphylococcus No. 101, a strain of HH bacteria isolated from sardine, was inoculated into ordinary and dark meat infusions of sardine containing 12 percent sodium chloride and incubated at 30t for 6 days. Histamine was detected in ordinary and dark meat infusions after 3 days. The amount of histamine detected in ordinary meat and dark meat infusions were 18.9, ug/ml and 10.9.μg/ml at third day, and 98.7μg/ml and 28.9μg/ml at sixth day, respectively. HH bacteria such as strain No. 101 seemed to produce histamine during curing and ripening of the producing process of the rice-bran pickles of sardine when the pickles were produced using the sardine in which HH bacteria occurred.

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Soymilk and soymilk enriched with vegetable oil which had been pasteurized for 30min at 80°C were fermented jointly with Lactobacillus bulgaricus, Streptococcus thermophilus and Bifidobacterium longum at 37°C for 20hr. The resulting fermented soymilks, as well as the plain a yogurt available on the market, were refrigerated for 10 days at 5°C, and changes in their bacterial cell counts and wheying-off were measured every 48hr in addition to the determination of changes in pH and acidity.
In the two fermented soymilks, the similar changes were observed in the decrease of pH and the increase of acidity during the storage period. Furthermore, there was a similar tendency for the viable cell counts of lactic acid bacteria to drop gradually, but a count equal to or more than 107 still was maintained after the storage period.
When considering the difficulty in maintaining the desired number of bifidobacteria in yogurt made from cow's milk, the finding that the viable cell counts of Bifidobacterium longum in the higher than 107 ml for the storage period seems to be of special interest from a point of view supplying Bifidobacterium longum to human.
Furthermore, the volume of whey formed on the surface of the fermented soymilk increased slightly with the elapse of storage time after manufacturing, but the increase was less than that of commercial yogurt.
Next, the soymilk and the soymilk with added vegetable oil which were heated for 30min at 80°C, 90°C and 100°C, and for 15min at 121°C, were fermented with the same starters above described, and the physico-chemical changes of the products during the storage were examined.
As a result, on day zero, the pH of the fermented soymilk made from the soymilk heated for 30 min at 90°C was the highest, and the acidity was the lowest.
Furthermore, the changes in the levels of pH and acidity during the storage were greatest in the fermented soymilk made from soymilk heated at 90°C for 30min.
In spite of the difference in heating temperature used for soymilk, the viable cell counts of lactic acid bacteria showed a similar tendency to decrease gradually during the storage period, but the counts were always maintained at equal to or more than 107ml for the storage period.
The volume of wheying-off formed in the two fermented soymilks increased as the heating temperature for soymilk is decreased. However, it was less than that of commercial yogurt.
On the otherhand, the effect of the vegetable oil added to soymilk on the prevention of wheying-off of the fermented soymilk was not clear.

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