The effects of aging temperature of Konjac sol in the process of making Konjac were studied at 35, 60, and 90°C by rupture testing and creep measurement of manufactured Konjac with a Rheometer. The mechanical properties (viscoelasticity, rupture stress, rupture energy, initial elasticity) of Konjac were decreased with an increase in aging temperature when the sample was prepared using"Arako" (dried slices of Konjac-root), especially remarkable in aging at 90°C. However, the viscoelasticity, rupture stress, rupture energy and initial elasticity of Konjac prepared from "Seiko" (isolated powder) were not affected by the aging temperature. Ther Rupture stress, rupture energy and initial elasticity of Konjac prepared from the powder with a smaller particle size (83-100mesh) were decreased evidently by aging at 90°C. By using the smallest particle size (200-330mesh) of powder, it was impossible to make Konjac gels. The viscoelasticity and rupture stress of Konjac made from the mixture of large (42-83mesh) and small (200-330 mesh) particle size powder (1:0.3) were decreased at 90°C. This suggested that the decrease in the viscoelasticity and rupture stress of the gel was induced by the smaller particle size of powder.
The Konjac sols of 200-330mesh was not glutinous and low viscosity, contrary to these of 42-83 mesh. This powder (200-330 mesh) was considered as "Tobiko" contained 30-40% in the crude "Arako" powder.

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The effects of polydextrose (3-27% (w/w)) on rheological and sensory characteristics of gellan gum gels (0.6-1.2% (w/w)) with and without calcium chloride or sodium chloride were investigated by dynamic viscoelastic measurement, compression test and sensory evaluation. The storage modulus (E') and the rupture stress of gellan gum gels without salts increased with increasing polydextrose concentration. The storage modulus (E') of gellan gum gels with a high concentration of calcium chloride (8mM) or sodium chloride (200mM, 400mM) was decreased by the addition of polydextrose. Gels being small stickiness, rupture stress and rupture energy were evaluated to have ease of swallowing, and gels being small springiness were evaluated to be preferable by the sensory evaluation.

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The electrophoretic property, solubility and emulsifying stability of the beef plasma protein (PP) were examined, and the quality of emulsion type salad dressing preparation using PP as the emulsifier was investigated. The major protein component of PP was water-soluble protein, serum albumin, indicating the solubility was 90.5% at pH 3.0. The emulsion with PP was stabilized in acidic condition at lower temperature. The emulsion type salad dressing prepared by adding PP (1, 2 and 3%) to the basic dressing material, which consisted of the mixture of salad oil and brewed vinegar (60:40, w/w), was characterized as the O/W type emulsion. It indicated the thixotropic fluid. The physical properties of the dressing preparation were dependent on the PP concentration as follows. (1) The emulsifying stability increased with increasing PP concentration. (2) Hunter whiteness decreased with increasing PP concentration. (3) The data of sensory evaluation showed that emulsion type salad dressing preparations using 1-3% PP were no problem in practice use on sensory acceptance.

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From the point of view of high utilization of antarctic krill, krill protein hydrolysates were prepared from antarctic krill meat and two species of shrimps by enzymic treatment using a protease. The hydrolysate prepared from each meat was added to lizard fish myofibrils in the concentration range of 2.5-12.5%, and the changes in the amount of unfrozen water in myofibrils associated with dehydration were analyzed by a differential scanning calorimetry. Ca²⁺-ATPase activity of myofibrils was simultaneously measured and the results were compared with those for the hydrolysates of two species of shrimps. The amount of unfrozen water was increased by the addition of each hydrolysate. A decrease in ATPase activity during dehydration was relieved synchronously with the increase of unfrozen water, indicating a close correlation between ATPase activity and the amount of unfrozen water. Addition of 5.0-7.5% of the hydrolysates showed the notice effect. These results suggest that the denaturation of myofibrils can be suppressed by the addition of the hydrolysates, since the hydrolysates constructed water molecules resulting in an increase in the amount of unfrozen water.

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Flavor of dried bonito was deteriorated and savory odors decreased gradually during storage when dried bonito was once crushed. In our previous studies it was proved that the decrease of volatile sulfur compounds caused the deterioration of flavor in crushed dried bonito during storage. Moreover, the addition of hydrogen sulfide produced the fresh odor of crushed dried bonito. These results suggested the sulfur compounds were the key flavor components. In this paper the reason of decrease of sulfur compounds in crushed dried bonito was examined.
Volatile sulfur compounds were analyzed by GC-FPD. The amounts of volatile sulfur compounds decreased during storage of crushed dried bonito. Among the sulfur compounds, hydrogen sulfide decreased most rapidly.
Dried bonito was fractionated to ether-extracted fraction, water-soluble fraction, and residue. We examined reactivity of these fractions with hydrogen sulfide. The water-soluble fraction allowed to decrease markedly in the amount of hydrogen sulfide. When the aqueous solution of the watersoluble fraction and hydrogen sulfide was kept in the closed vessel for a few days, hydrogen sulfide disappeared and formed the pale precipitate of sulfur. It was suggested that hydrogen sulfide could be oxidized to sulfur powder by ferric ion and histidine in dried bonito. This reaction was probably catalyzed by the complex of Fe³⁺ and histidine.

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Fish sauces were prepared from round silver carp using soy sauce Koji inoculated with Aspergillus oryzae plus lactic acid bacteria Tetrogenococcus halophilus (No. 1), soy sauce Koji (No. 2), lactic acid bacteria (No. 3), and no starter microorganisms (No. 4). These fish sauces were compared in the volatile compounds identified by SPME method and GC/MC analysis among Nampla from Thailand and Fujian fish sauce (FFS) from China. In Nampla, many kinds of volatile acid (VA) including butanoic acid were detected. However, in the fish sauces Nos. 1 and 2, no butanoic acid was detected, and there was much of VA in the fish sauce No. 1 while there was some VA and alcohols in the fish sauce No. 2. In the fish sauces Nos. 3 and 4, a few kinds of VA and 1-penten-3-ol were detected while there were many kinds of hydrocarbons in the fish sauce No. 3, and alcohols in the fish sauce No. 4. In FFS, much of VA including butanoic acid and trimethylamine was detected. The result of sensory evaluation indicated that the panelists preferred the flavor of the fish sauces Nos. 1 and 2 to that of Nampla, while they rather disliked FFS, and the responses to the fish sauces Nos. 3 and 4 were at almost same level as that to Nampla.

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The DPPH radical-scavenging activities and polyphenol contents of methanolic extracts from aerial parts of buckwheat (Fagopyrum esculentum Moench) during growth period were investigated. The total polyphenols in the extracts decreased from germination to 15 days after, but thereafter, it increased up to the 23rd day at early in the flowering time. Although the change in the DPPH radical-scavenging activitiy was similar to that of the total polyphenol content, the activity on the 23rd day was similar to or higher than that on the first. Whereas the HPLC pattern of the extracts during the early stage of development showed five main peaks including rutin, the number of peaks decreased with increasing days, and only rutin was detected on and after the 19th day. UV spectra of the peaks detected in the HPLC chromatogram of the extracts of buckwheat seedlings, revealed that they contained four flavonoid compounds except for rutin. Two peaks of the chromatogram, which were not detected by an electrochemical detector at +300mV, were identified as vitexin and isovitexin by comparison with HPLC data of the isolated compounds from buckwheat hulls. Other two peaks, which were detected by electrochemical analysis, were isolated by Sephadex LH-20 chromatography, preparative HPLC with ODS and a polymer based column. They were identified as orientin and isoorientin by NMR and FAB-MS spectrometric data. The contents of these flavonoid compounds were abundant in buckwheat seedlings along with rutin.

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The effect of Hatakeshimeji (Lyophyllum decastes Sing.) diet on blood pressure in spontaneously hypertensive rats (SHR) was studied. The animals were fed experimental diets for 21 days and their cystolic blood pressures were measured by tail cuff method. The rats fed the diets containing powdered Hatakeshimeji fruit body at the levels of 10% (H 10-group) and 20% (H 20-group) showed a significantly lower blood pressure compared to the control group (C-group, Hatakeshimeji free). At the last day of the feeding term, the blood pressures of the C-group, the H 10-group, and the H 20-group were 227±9, 207±9, and 188±5mmHg, respectively. The hot-water extractable fraction of Hatakeshimeji lyophilized powder (HWE-A) was prepared through extraction in boiling water, followed by extraction with 75% acetone. The HWE-A showed 20 and 18% lower blood pressures 4.5 hours after the intragastric administration and 1.5 hours after the intraperitoneal injection, respectively.

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