In order to assess the cooking quality and some properties of cut-and-stored potato, potatoes were sliced 1-cm thick and then quartered. The cut slices were immediately dipped for 5 min in one of the following fluids : distilled water, 0.05 M L-ascorbic acid (AA), 0.05 M sodium L-ascorbyl-2-phosphate (AAP-Na), or 0.05 M magnesium L-ascorbyl-2-phosphate (AAP-Mg). After draining, the slices were packed in aluminum-laminated plastic bags with or without evacuation. The bags were then stored at 4 or 20°C for 1 to 6 days. Some merits were observed when the cut potatoes were stored : there was no decrease in the total vitamin C content, and there was in fact a gradual increase in the percentage of total vitamin C remaining after cooking. One cause of these phenomena might be that cell wall thickening, which was observed by optical and electron microscopy, occurred on the cut surface of the samples during storage. This cell wall thickening also induced an inhibition of crumbling of the slices during cooking. The best storage condition to inhibit browning of the potato slices was evacuated storage at 4°C, and the second best was non-evacuated storage at 4°C. Dipping in 0.05 M AA and its derivatives inhibited browning of the potato slices stored without evacuating at 4°C, and the derivatives still showed some inhibition for the slices stored even at 20°C. Acceptability by a sensory evaluation proved the highest when the cut slices were stored with evacuation at 4 °C, and the second highest when stored without evacuation at 4°C.

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To determine the effect of aging time after thawing on the palatability of frozen beef, several objective measurements and sensory evaluations were made on beef sirloin samples (the Longissimus thoracis muscle). The samples were aged at 0 °C for 0, 2, 5 or 10 days after thawing. The following results were obtained :
1) Aging after thawing improved the water-holding capacity, decreased the cooking loss and increased juiciness.
2) The levels of free amino acids increased with aging.
3) The shear force and compression values decreased markedly with aging. In addition, there was a tendency for the structure of the muscle fibers to become fragile.
4) Sensory tests showed that the texture and overall palatability were improved by additional aging after thawing. However, no significant differences were found between thawed beef aged for 5 days and for 10 days.
The results suggest that before cooking, additional aging after thawing would improve beef palatability, with a minimum aging time of 5 days.
The rate of aging in the experimental samples (aged after thawing) was faster than that in the standard samples (aged at 0°C without freezing) as evaluated by the level of free amino acids, and the shear force and compression values.

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Dry and evaporative heat resistance of hanbok ensembles, traditional Korean ladies' costumes, were measured and the effects of wind on heat resistance were examined in this study. The ensembles tested consisted of a set of under wear, four different chima-jogori, materials of ramie, silk nobang, silk and polyester, and durmagi, which is worn over the chima-jogori to keep warm during the winter. In order to measure the heat resistance, a thermal manikin in dry and sweating conditions was used.
The results were as follows :
1) As for dry heat resistance, the durmagi ensemble had the highest of all, followed by chima-jogori ensembles made of silk, polyester, and silk nobang, with the chima-jogori made of ramie having the lowest. Dry heat resistance showed a significant correlation coefficient of 0.80 with the fabric thickness in still air, but the resistance of ensembles except silk and durmagi decreased due to the air permability of the fabrics in windy conditions.
2) Evaporative heat resistance of the durmagi the ensemble was also the highest of all and the order of resistance for each ensemble was similar to that for dry resistance, and the evaporative heat resistance showed a significant correlation coefficient of 0.88 with the fabric thickness in still air. The evaporative heat resistance in the ramie, polyester and durmagi ensembles were slightly affected by wind.
3) Changes in dry and evaporative heat resistance in traditional Korean costumes were not caused by the shape or contraction of the costume, but by the thickness (including lining) and the air permeability of the fabric. Similar results have been observed for the Kimono, the traditional costume of Japan.

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[in Japanese]

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[in Japanese]

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[in Japanese]

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