Effective parameters to evaluate the poultice up process (PUP) which has conventionally been used for forced ventilation drying processes of foods were newly proposed. Using a fish paste sausage as a model food, drying efficiency was quantitatively evaluated in connection with tempera-ture and the PUP. The rate analysis of the redrying step after the introduction of PUP process presented an adequate diffusion mechanism of water in the sausage. We introduced two para-meters : a drying rate ratio (R) which can evaluate acceleration rate due to the PUP and an effective-ness factor of drying time (Ef) which shows the reduced period of drying process due to the PUP. The R-value was effectively used to compare the drying rate and to determine the effective period for PUP-introduction in various drying conditions. The Ef-values were classified into two groups depending on the starting time of the PUP. The two characteristic aspects of Ef were reasonablyexplained by two different mechanisms of water diffusion according to the water content of the sample. It was proved that the values of R and Ef are useful to evaluate quantitatively the PUP.

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The vapor pressures of three kinds of liquid food (milk, dry milk solution, skim milk) of concentrations between 6 and 40% (w/w) were measured at temperatures between 10-60°C by a static method. The results measured were fitted to four vapor pressure equations (Clausius-Clapeyron, Antoine, Kirchhoff and Riedel equation), respectively. As a result, Antoine's equation was the most suitable one to relate temperature with the vapor pressure data of sample solutions. The enthalpies of vaporization in sample solutions were calculated directly from the Clapeyron's equation utilizing Antoine's equation without any assumptions in the Clausius-Clapeyron's equation and the Othmer plot principle. Moreover, effects of concentration on the vapor pressure of sample solutions were also investigated. The results suggested a linear relationship between the logarithm of vapor pressure and concentration. Therefore, a new empirical equation with five parameters relating temperature and concentration to vapor pressure, which was derived from adding concentration dependency to Antoine's equation, was developed. Using this equation, the enthalpies of vaporization in sample solutions were calculated from Clapeyron's equation. Furthermore, an empirical equation for the enthalpies of vaporization for sample solutions was proposed as a function of temperature and concentration to be convenient to the practical use.

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The antioxidant activity against sardine oil and linoleic acid of hot water extract from Stevia rebaudiana was compared to DL-α-tocopherol (DL-α-Toc), butyl hydroxy anisol and green tea extract. The sardine oil oxidation was assessed from the formation of peroxides. The concentration of odor components was measured by a portable type odor concentration meter equipped with a metal oxide semiconductor. Linoleic acid oxidation was assessed by the ferric thiocyanate method. Stebia rebaudiana extract effectively inhibited hydroperoxide and volatile component formations in sardine oil. The oxidation was more effectively inhibited by the hot water extract from S. rebaudiana than DL-α-Toc or green tea extract at the same concentration in sardine oil. Additive effects were observed when the extract was mixed DL-α-Toc or citric acid.Some effective fractions were separated from the extract by dialysis, column chromatography and thin layer chromatography. Some of the antioxidant fractions were polyphenolic compounds. The component which showed the highest antioxidant activity contained large amounts of potassium.

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Stevia rebaudiana hot water extracts were shown to have highly antioxidant activity against sardine oil and linoleic acid. The most active fraction which was reported in the previous paper contained large amounts of potassium. The activity was decreased by the removal of cations from the fraction by ion exchange chromatography. The activity was recovered by the addition of potassium carbonate to the fraction from which cations were removed. It was suggested that the potassium ion participated in the antioxidant activity of S. rebaudiana. When antioxidant activities of inorganic salts were investigated, it was ascertained that potassium carbonate (K₂CO₃). potassium bicarbonate (KHCO₃), sodium phosphate (Na₃PO₄), potassium chloride (KCl) and sodium carbonate (Na₂CO₃) functioned as antioxidant compounds against linoleic acid. The most active inorganic salt was potassium carbonate. lt was suggested that the function of the antioxidant activities of S. rebaudiana was mainly due to the scavenging of free radicals and next to the scavenging of superoxides. The activity of potassium carbonate was also mainly due to the scavenging activity of free radicals.

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The compositions of aroma components were compared in three types of rice miso, red salty rice miso (sekishoku-karakuchikei komemiso), thin-colored salty rice miso (tanshoku-karakuchikei komemiso), and weak-salty rice miso (komeamamiso) which were produced from soybeans and rice, barley miso (mugimiso) produced from soybeans and barley, and soy miso (mamemiso) produced from soybeans only. In addition, the influences of difference in the materials and the manufacturing process of miso on the formation of aroma in 5 types of miso were discussed. Eight samples in each type of miso were collected from products highly evaluated at the 34th National Miso Competition, and their aroma concentrates were prepared. Aroma components concentrated on a porous polymer were eluted with ether, and analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The similarities among GC patterns obtained from 5 types of miso were evaluated using the concentrations of their 107 compounds detected. The results showed that the GC patterns of red salty rice miso were almost similar to those of thin-colored salty rice miso and barley miso, but not to those of both weak-salty rice miso and soy miso. 4-Hydroxy-2 (or 5)-ethyl-5 (or 2)- methyl-3 (2 H)-furanone (HEMF), a character impact compound of red salty rice miso and shoyu, was identified in thin-colored salty rice miso and barley miso which are usually aged after fermentation process. However, no HEMF was detected in weak-salty rice miso and soy miso. 4-Ethylguaiacol, which was one of the characteristic aroma components in shoyu, was found in barley miso and soy miso as an important aroma component, but was not detected in miso produced from rice and soybeans.

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Peptic digestibility of bovine β-lactoglobulin in the presence or absence of grilled cow's meat homogenate was analyzed by 16% SDSpolyacrylamide gel electrophoresis and Western blot analysis with anti-bovine β-lactoglobulin. Most of proteins in the grilled cow's meat homogenate were rapidly digested by pepsin. β-Lactoglobulin, a major cow's milk allergen, was resistant to the peptic digestion, but the peptic digestibility of β-lactoglobulin was promoted in the presence of grilled cow's meat homogenate. These results suggest that a low level of antigenic polypeptides may remain after peptic digestion of grilled cow's meat, and cow's meat intake may improve peptic digestibility of indigestible proteins in the stomach.

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