Tree-ripe 'Irwin' mango fruit grown under the green houses in Japan have excellent quality. Unfortunately, their harvesting period is very limited and storability is very less. Therefore, a method for preserving the fruit quality is highly needed. Temperature and the gas composition are the most important factors affecting the rate of respiration and ultimately the fruit quality attributes. Respiration rate is the necessary parameter for designing the storage conditions. In the present investigation, the effects of storage temperature (5, 15, 25°C) and gas composition on the O₂ consumption and the CO₂ production have been studied by using the flow through system. The ratios of the respiration rate under controlled atmosphere conditions (1.6 to 20.7% O₂, 0. 2 to 10.2% CO₂, balanced with N₂) were calculated against the values under normal air condition. The results obtained on the respiration rate and the respiration quotient suggest that low temperature in combination with CA gas composition of carbon dioxide around 10% will be effective to suppress the respiration rate of tree-ripe 'Irwin' mango fruit, and oxygen should be higher than 5 % to avoid the anaerobic respiration.

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'Hiratanenashi' fruit is the most popular Japanese persimmon (Diospyros kaki Thunb.) in Japan.It has fine flesh and good taste after its astringency was removed. But the fruit has very short shelf life, because of rapid softening after removed astringency. 'Tuyu' fruit is also popular persimmon fruit which is the non-astringency cultivar. The present study was conducted to investigate the relationship between the changes in fruit firmness and cell wall composition (pectic and hemicellulosic composition) and 'Eliratanenashi' and 'Tuyu' cultivars. (1) Sugar of phenol-acetic acid-water (PAW) fraction from 'Tuyu' fruits were increased, but the content of 'Hiratanenashi' fruit did not change during storage. Soluble polyuronide contents increased both cultivars during storage. (2) The contents of cyclohexane-trans-1, 2-diamine tetra-acetate (CDTA) soluble polyuronide and sugar contents of 'Fuyu' fruit was decreased markedly during from 10 day to 15 day in storage. 'Hiratanenashi' fruit was not change during storage.The contents of Na₂CO₃ soluble polyuronide and sugar contents of both cultivars were similar pattern of CDTA soluble fraction. (3) The contents of guanidium-thiocyanate (GTC) -soluble and KOH-soluble sugar from hemicellulosic components did not change in 'Hiratanenashi' and 'Tuyu' fruit during storage. These results indicated that the fruit softening of 'Hiratanenashi' and 'Tuyu' are attributable to increase of water-soluble polyuronide and decrease of water-insoluble polyuronide contents. Pectic component in 'Fuyu' fruit is much quantity comparison with 'Hiratanenashi' fruit, and polyuronide and sugar contents in pectic component of both cultivars have a similar tendency to fruit firmness.

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Koji-mold for producing acid was obtained from protoplast fusion. One mutant was derived from the original strain Aspergillus oryzae N-1 isolated from Ina-Koji and exhibited high acid production. The other was derived from the original strain Aspergillus oryzae RIB-176 for sake and exhibited high amylase activity.The mutants of the fungus were induced by successive N-methyl-N'-nitro-N-nitrosoguanidine (NTG) treatment. The protoplasts were obtained from mycelium of two nutritionally complementary mutants using Usukizyme of Trichoderma enzyme. When the koji-mold formed heterocaryons production of protoplast fusion was used for making sake, the acidity of the ripening sake and the mash was double higher than used strain A. oryzae RIB-176.

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Inhibitory effect of onion juice on the browning of various fruits and vegetables was examined. When fruits and vegetables were ground in the presence of the onion juice, the juice suppressed the browning of butterbur (Petasites japonicus Miq.), burdock (Arctium Lappa L.), eggplant (Solanum melongena L.), potato (Solanum tuberosum L.), sweet potato (Ipomoea batats Poir.), mushroom (Agaricus bisporus Sing.), seed and placenta parts of sweet pepper and bell pepper (Capsicum annuum L.), apple (Malus domestica Mill.), loquat (Eriobotrya japonica Lindl.), plum (Prunus salicina Lindley), cherry (Prunus avium L.), peach (Prunus Persica Batsch) and papaya (Carica Papaya L.). However, the juice did not suppress the browning of shiitake (Lentinus edodes Sing.) and the rind of banana (Musa paradisiaca L.). With cut fruits and vegetables, dipping in the onion juice suppressed significantly the browning of lotus (Nelumbo nucifera Gaertn.) and apple, and partially potato, while it had no effect on burdock. The browning of the rind of banana was reversely promoted by onion juice.

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