The respiration rates of eggplant, tomato, sweet pepper, cucumber, broad bean, pea, Japanese radish, carrot and Chinese cabbage were measured for 48 hours under air, 1% O₂, 4%O₂, 7% O₂ and 10% O₂ atmospheres. The respiration rates were determined by measuring the rates of CO₂ production from plant materials using the gas separation membrane-modified air system (GSM-MAS) · CO₂ evolution analyzer and the pressure swing adsorption-modified air system (PSA-MAS) · CO₂ evolution analyzer which were developed before. Respiration rates of all vegetables started to decline within a few hours after reduction of oxygen concentration in a storage chamber. The respiration rates were lower under the low oxygen atmosphere as compared to those under air condition in all vegetables. The linear relationship was observed between the concentration of oxygen in the atmosphere and the rates of CO₂ production from eggplant and carrot. Respiration rates were considerably decreased even at 10% O₂ atmosphere compared to those under air in eggplant and carrot. In other vegetables, however, respiration rates were slightly decreased under 7% or more oxygen conditions. Below 7% O₂ level, respiration rates were obviously reduced at the lower oxygen levels as compared to those under air.

View full abstract

Effects of air-exposure at low temperature (1°C) for 2 hrs after processing on growth of microorganisms and browning in shredded cabbage during holding at 20°C were studied.
Air-exposure at low temperature reduced growth of microorganisms and retarded browing, and effects of this treatment were almost same as NaOCl treatment or washing.
Air-exposure at low temperature retarded browning but either cooling or slight drying did not retard it. Only combination of cooling and slight drying after processing was effective to the retardation of browning. Changes in contents of phenolic substances and free amino acid were little and shredded cabbage formed lignin during holding. There was no difference in their contents and forming of lignin among samples.
Retarding of browning in thick shredded cabbage (1.5mm) was more apparent than that in wide shredded cabbage (3-5 mm).

View full abstract

Near infrared (NIR) spectroscopy was employed to determine hardness of intact mume fruit. Fruits were supplied to a NIR spectrophotometer and the absorbance at wavelength between 1100 and 2500nm (2nm intervals) was measured. The correlation between hardness values (kg) obtained with hardness meter and those obtained by NIR were examined by multiple linear regression analysis. The strongest correlation was obtained between NIR values predicted by 5-wavelength regression and those obtained with hardness meter. The multiple correlation coefficient was 0. 91 and standard error of prediction was 0.32kg. It was proved that NIR is a useful method for determination of hardness of mume fruit.

View full abstract