For the elucidation of CO₂ evolution mechanism, the sugar contents and enzyme activities of chilling-injured fruits which were stored at 6°C for 4 days (B) and for 9 days (C) were compared with those of mature green healty fruit (A), during the course of after-ripening at 20°C.
In A and B, the marked increases of pyruvate decarboxylase and alcohol dehydrogenase (ADH) activities, sugar and ethanol contents were found in parallel with a drastic increase of CO₂ evolution of so called "climacteric rise" with a lag of several days. While only slight increases of isocitrate dehydrogenase and glucose-6-phosphate dehydrogenase (G6P-DH) activities and decrease of O₂ consumption were observed during the same period. In C, however, a transient increase of CO₂ evolution accompanying an increase of sugar contents occurred immediately after storage at 20°C. In this group, G6P-DH and phosphoenolpyruvate (PEP) carboxykinase activities were relatively high even at early phase of after-ripening. As the pulp became to soften, a second peak of CO₂ evolutioa was seen and drastic increases of pyruvate decarboxylase and ADH activities as well as ethanol contents were observed.
These results may be suggested that the first peak of CO2 evolution in C mainly due to G6PDH and PEP- carboxykinase activities, and the second peak corresponding to the climacteric rise in A and B due to pyruvate decarboxylase activities.

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Effects of drying temperature and relative humidity on drying rate of agar jelly were studied.
When jelly was stored under various relative humidity (RH0-90%) at 300°C, jelly was driedbelow RH 80% and drying rate was similar to each other under RH0-43%.
When dried at 40°C, 50°C and 60°C under RH40%, 60% respectively, drying rate of jelly was increased as the temperature rose and was delayed as jelly moisture decreased, especially, under the low humidity.
These results indicated that the delay of drying rate was due to over-drying of the surface of jelly.
Changes of physical properties of jelly on various drying stage at 50°C and 60°C were measured.
The gel strength of jelly was unchanged till its moisture content was decreased 6-7% from initial moisture, after that its values were increased rapidly with decreasing of moisture content.
On the creep test, E₁ (Young modulus of Hooke type)was increased but E₂, E₄ and η₂ (Young modulus of Voigt type and Plasto-elastic type, viscosity of Voigt type) were decreased with progress of drying stage.
The chages of η₃ (viscosity of Newtonian type) were decreased at 50°C of drying temperature but increased at 60°C.
Those all elements were remarkably changed on drying at 50°C than at 60°C.

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For food and medical application, a strain of spore bearing lactic acid bacteria was isolated from the soil and it's microbial properties were investigated. This strain, which was gram-positive and catalase positive, produced L(+)-lactic acid and bore spores in aerobic incubation was presumed to belong to Bacillus coagulans HAMMER.
It was revealed that the strain has more excellent properties in preservability, heat and acid stability than commercil preparations from the view point of application for food and medical use.

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Application of a pectin trans-eliminase preparation from Asper gillus japonicus to fruit juices was investigated. A small amount of pectin trans-eliminase was enough for the complete clarification of an apple juice, but a considerable amount of the enzyme was necessary for clarification of grape juice. Optimal conditions of pH and temperature for clarifying fruit juice were pH 3-4 and around 50°C. However, slight differences in the effect of pH and temperature on fruit juice clarification were seen between apple and grape. When pectin trans-eliminase activity of several preparations obtained from this mold was adjusted to the same level, the ability of clarifying an apple juice was almost same, but that of clarifying a grape juice varied widely. These results suggest that unlike apple juice clarification, other enzyme(s) in this preparation may play a role in the grape juice clarification.
Pectin trans-eliminase preparation was effective on the fittration of crushed grapes resulting in the increase of yield(about 11%)and the improvement of filterability of the juice.

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A new phenomenon which is called the inflation of seeds was discovered, when the seeds of various species such as peanut, soybean, corn and sesame were immersed into hydrogen peroxide solution (HPO). The seeds in HPO generated oxygen gas rapidly at the surface of the seed coat and of the endosperm by an action of catalase existing in the seed. The oxygen gas was accumulating in the space between the seed coat and the endosperm, consequently it pushed the swelled seed coat out to make the seed like a ball, without the endosperm absorbing water.
In the process of the inflation, each seed showed particular characteristics, according to the species, in regard to the rate of the inflation, position on the seed at which the inflation started, water absorption into the endosperm, and final volume of the seed. A striking distinction between the swelled and the inflated seed can be explained as follow, in the former, the entire seed is swelled due to the occurrence of water absorption, while in the latter the seed coat expansion occurs with oxygen gas jacket-surrounding the endosperm which keeps its original shape.
It is expected that a new blanching procedure may be introduced in food technology, as the inflated seed can be easily skinned by means of a usual nut blancher in wet state or even after drying.

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