Physiological and textural changes of Balsam pear (Momordica charantia L.) fruit were investigated during development and subsequent storage. The fruits were harvested at six developmental stages of A, B, C, D, E and F, with A (immature) and F (overripe). The fruit harvested at stage C (harvesting maturity) were packaged with polyethylene film (20μm in thickness) bags and stored at 1, 10, 20 and 30°C. 1) The flesh firmness decreased with fruit development and this decrease hastened during fruit ripening. In the stored fruit, the flesh firmness decreased more rapidly at higher temperature than at lower temperature. 2) The respiration rate changed little during the early stages of fruit growth and increased during fruit ripening, showing a typical phenomenon as a respiratory climacteric. The CO₂ concentration in the polyethylene film bags of stored fruit increased more rapidly at higher temperatures. 3) The ethylene production was very low in all stages of the fruit development and was the lowest at the harvesting stage C. The ethylene concentration in the polyethylene film bags of stored fruit increased earlier at higher temperature and there was no increase of ethylene concentration in the package at 1 °C. 4) The water-soluble pectin content constantly increased during fruit development, the increase being maximum during the fruit ripening. The hydrochloric acid-soluble pectin content continued to decrease during fruit development. The higher temperature in the fruit storage made the water-soluble pectin content elevated and the hydrochloric acid-soluble pectin content reduced. 5) Polygalacturonase activity was at a low level during fruit growth and increased significantly with fruit ripening, while pectinesterase activity was relatively high and changed little during fruit growth and ripening.

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Fe-EDTA concentrations of culture solution in hydropnics were changed for improving the quality of herbs, peppermint, sage, perilla (Perilla frutescens Britton), basil, hyssop and Japanese honewort (Cryptotaenia japonica Hassk). Culture solution contained Ca (NO₃) ₂·4H₂O : 45g, KNO₃ : 36g, MgSO₄·7H₂O : 22.5g, NH₄HPO₄ : 6.75g in 45l water. High concentration of Fe-EDTA (0.296g/e) inhibited the growth of these herbs. The high Fe-EDTA (0.296g/l) concentration with peppermint resulted in the higher contents of chlorophyll, o-diphenol, total phenols and free amino acid than the control (0.148g/l).

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Cutting tests were performed in order to investigate the differences in physical properties between two types of standard cheese produced independently, and composite cheese (consisting of a Gouda side and a Cheddar side) produced using the production processes used for the two types of hard cheese (Gouda cheese and Cheddar cheese). All the cheese types in this study demonstrated a tendency toward softening, with decrease in hardness, cutting strength and cutting energy, as the ripening process advanced. A t-test was performed to compare the measured values of both sides of the composite cheese with their counterpart standard cheeses. The results revealed an increase in the number of measured parameters that exhibited significant differences (P<0.05) between the 60 and 120 days of ripening. Thus the differences in physical properties between the composite cheese and the two types of standard cheese produced independently were confirmed.

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The total soluble solids of the sugar apple increased and then decreased a little during ripening at different storage temperatures, glucose, fructose and sucrose were incrased gradually during the fruits ripening, with the fruits stored at 26 and 21°C being higher in the sugar contents than those stored at 16°C. The decrease of starch in the fruits stored at 26 and 21°C was quicker than those stored at 16°C. The fruits stored at 21°C led the higher activity in amylase than the others.

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Strawberries after petal fall were tagged and sprayed with 2000 ppm CaCl₂, Ca-chelate (200 ppm as Ca⁺² chelated with a carboxylic acid compound extracted from plant materials), 200 ppm Ca-chelate plus 12.5 ppm boron (CALHARD^®, Otsuka Chem.), and 150 ppm of the carboxylic acid compound (the chelating agent) or water as a control. The spray in a repeated 3 or 4 times a week until harvest at the rate of 200 liter · 1000m^-2 with a hand pressure sprayer. Tween-20 (0.1%) was added as a wetting agent in all treatments. All Ca treatments increased the fruit firmness, reduced the respiration rate at harvest, and prolonged the postharvest life. Ascorbic acid content in Ca sprayed berries was higher than those of the control not only at harvest but also after 2 days at 20°C. Ca treatments did not significantly affect the titratable acidity, total soluble solids, nor the peel color. The Ca-chelate or with boron was as effective as CaCl₂ but at 1/10 the concentration of the latter. The chelating agent per se exhibited no significant effects on improving fruit firmness nor delaying the deterioration.

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