It was found that the thermal conduction in a series of O/ W edible emulsions was influenced by the size and size distribution of the dispersed oil globules. The examination was made on five emulsion samples in different size distributions of oil globules at the same volume fraction (φ=0.8).
The results obtained indicate that the increasing velocity of inside temperature of the emulsion samples decreased with decreasing mean size of the dispersed oil globules during heating procedure. Accordingly, the thermal characteristics such as thermal conductivity, thermal diffusivity, retardation time of heating procedure, etc. are much influenced by the size and size distribution of the dispersed oil globules with the same volume fraction in O/W emulsions. In addition to the above, the apparent viscosity and Casson's yield value in the flow curve of the sample emulsions increased while the size of the dispersed oil globule decreased.

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Kombu is a kind of tangle or soup material in Japan. Free amino acids by an amino acid analyzer and total arsenic by HG-AAS method and the speciation analysis of arsenic by HPLC/ICP-MS method were analyzed in Kombu extract prepared under various extraction conditions.
It was found that about 90% of free amino acids and 40-70% of total arsenic in Kombu were eluted into the soup. Free amino acids increased by prolonged soaking or heating, particular by soaking time. It was confirmed that most of the total arsenic contained were as nontoxic or less toxic organic compounds such as arsenosugar in Kombu and in the soup.
Soaking and boiling increased the total arsenic in the soup, though in particular, the latter had a much greater influence, and the elution mechanism of arsenic was different from that of free amino acids.

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Effects of aging and gender on taste sensitivity were assessed by measuring detection and recognition thresholds of sodium chloride, sucrose, and citric acid. Also, relationship between each taste sensitivity and food preference was examined. The subjects were 22 males and 32 females aged over 65 and 54males and 54 females aged around 20. A significant overall effect of aging on the taste sensitivity was found. The elderly people showed statistically significant higher detection thresholds for sodium chloride and citric acid and recognition thresholds for sucrose and citric acid than the young ones. There was also a gender effect on the sensitivity for citric acid; the elderly males were less sensitive than the elderly females. All threshold values analyzed by probit method, except in the detection threshold for sucrose, were the following; young females, young males, elderly females and elderly males, arranged in ascending order. It was recognized that the subjects who were less sensitive to sodium chloride, preferred salty foods such as “tsukemono” or “shiokara” more than those with high sensitivity. No relation was found between food preference and taste sensitivity.

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The breaking properties of test foods cooked in pans made of carbon steel (Fe) and fluoroplastic coated aluminum (Al-F) was examined.
(1) The time of cooking with Fe-pan was 70% shorten than that with Al-F-pan.
(2) Sensory evaluation of the external heating progression such as the brown color with the Fe-pan was thicker than with the Al-F-pan, but the eating quality and texture before heating was remarkably retained.
(3) Considering such external factors of the test foods as the surface temperature and the brown color, a difference in texture between that with the Fe-pan and Al-F-pan was apparent. The reasons cited for the differences were the delay in internal temperature rising and moisture evaporation on test foods.
(4) The batter test made it sure that the coagulation rate of cooked samples with Fe-pan was lower than that with Al-F-pan at the time when a uniform browning was obtained.

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The influence of various extraction conditions and quality of water on the taste of coffee was sensory evaluated, and the relation between the amount of chlorogenic acid (Chl) in Coffee and the sour taste was investigated.
Significant difference was hardly observed in three types of coffee by sensory evaluation of the extraction temperature, but when the three coffee samples were extracted at high temperature, two types of coffee developed dark color. It was found that extraction at 85°C and the coffee appliances used scored significantly low in the evaluation. Coffee with little Chl exhibited a weak sour taste. Hard water used in two types of coffee showed significantly low scores in the overall evaluation since it yielded an intensely bitter and weak sour taste coffee extract. A positive correlation between the amount of Chl and the sour taste was observed. Thus the amount of Chl can be used as an index of sour taste.

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“Sikhe” is a traditional Korean salted and fermented fish. The principal components such as free amino acids, fatty acids, minerals, and water, and acidity and microorganisms in 6 “Sikhe” samples purchased in Kangnung city, Korea were analyzed.
The results were as follows:
1. The contents of sodium, potassium and salt and the water activity of Sikhe were 1,157±279mg/100g,261±63mg/100g,2.9±0.7% and 0.945±0.018, respectively.
2. The total free amino acid content of Sikhe was 2,277±273mg/100g, and glutamic acid, γ-aminobutyric acid (GABA) and alanine were the major ones.
3. The major fatty acids were linolenic, oleic and palmitic acids, n-3 polyunsaturated fatty acids such as icosapentaenoic and docosahexaenoic acids, both from fish, occupied 16.3% of the total fatty acids.
4. The average counts of viable cell, lactic acid bacteria, anaerobic bacteria and psychrotrophic bacteria were 7.48 (log./g),7.46 (log./g),7 vL 35 (log./g) and 3.72 (log./g), respectively.

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