The changes in protease activities were studied during the development and the storage of kiwifruits, (Actinidia deliciosa (A. Chev) C.F. Liang et A.R. Ferguson Cv. Hayward, Abott, and Bruno) harvested from 3 to 25 weeks after anthesis. The stability of protease in acetone powder was also examined. The amounts of free sugars, free amino acids, alcohol insoluble substances and pectic substances were measured, and the correlation between these values and the protease activities were examined.
1. The protease activity increased according to progress of the development. The activity showed high correlation with the yield of acetone powder.
2. The protease activities of kiwi fruits tend to decrease slightly during the storage at 5°C for 20-55 days or at 20°C for 20 days respectively.
3. Protease activities of acetone powder were stable for up to 90 days during the storage at 1°C for 30-150 days.
4. Soluble protein contents increased during the development of the fruit, and a high correlation was shown between the amount of the protein and the protease activity.

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Ice-nucleating Pseudornonas syringae cells were entrapped in aluminium alginate to prepare the ice-nucleating capsule usable as ice nuclei for freezing of sea water, dimethyl sulfoxide and alcohol aqueous solution. Sea water with an ice-nucleating capsule (7×10⁶ cells) froze at -1°C, whereas that without an ice-nucleating capsule supercooled to -7°C. Freezing finished time differs markedly according to dimethyl sulfoxide aqueous solution in the presence and absence of an ice-nucleating capsule. The effect of the mono-substituted alcohol/H₂O systems on the ice-nucleating temperature of an ice-nucleating capsule almost linearly increased with an increase in the hydrophobic substituent constants of the mono-substituted alcohols. We conclude that the application of the ice-nucleating capsule to freezing of sea water, dimethyl sulfoxide and alcohol aqueous solutions is very promoting.

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Partially processed pepper fruits were prepared cutting lengthwise from apex to stem end with 10mm width (line slice) and crosswise with 10mm width (ring slice). They and whole fruits were sealed in polyethylene bags (0.02mm thickness) and stored at 1°C and 20°C Softening and decay of cut surface were accelerated by cutting, and the deterioration rate of line slices was obviously faster than that of ring slices.
As the sample for chemical analysis, pulp of 1mm thickness from cut surface was used. Contents of alcohol insoluble substances and phenols showed no change in whole fruits, while those in line and ring slices increased a little at early period of storage at both temperature. Free amino acid content of both slices decreased during storage, whereas it increased in whole fruits. Changes in these compounds, however, no difference was observed between ring and line slices.
Difference by shredding direction was obvious in the change of pectic substances. Hydrochloric acid soluble pectin content in line slices decreased drastically showing 90% reduction in 2 days at 20°C as compared with 50% reduction of ring slices.

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