In order to investigate on the swelling process of the dried foods, the changes of volume of 17 samples by the swelling were measured and the swelling ratios were examined. The volume no meter which was reported in the previous papers was used to measure the small change of volume of the samples. As a result, the volumes of most samples tended to be saturated for about 2 hours in water at 21°C, but some of samples of marine products did not show the saturation by soaking after even 24 hours.
In addition, in order to reveal the effect of temperature on the swelling ratio, soaking was made at 83°C. The swelling ratios of specimen which were soaked at 83°C showed the larger values than those at 21°C, however, some of an undaria, Shiitake mushroom and a Jew's ear which were soaked at 21°C showed the larger swelling ratios than those at 83°C.
Moreover, we discussed on the swelling mechanism of the dried foods.

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YOSENA is a famous green coloured foodstuff, which has been used in Japanese cuisine since 1701. YOSENA is usually formed by heating green vegetable juice, floating on the surface, over 60°C at pH6-7. The yield of YOSENA of vegetables was in the following order: spinach>Japanese radish (Daikon)leaves>turnip leaves>parsley>leaf mustard>celery>chingentuai>broccoli>green Welsh onion.
YOSENA was formed from juices of asparagus, mitsuba and perilla leaves but their LPC (leaf protein concentrate) was obtained by filtrating the heated juice. A crown daisy could form YOSENA only under pH 6.
The small particles of YOSENA from Japanese radish leaves were decreased by treatment of the vegetable juice with protease and lipase. The yield of YOSENA was also decreased by the addition of N-ethylmaleimid (NEM) to the juice and blocking the SH-radicals on the vegetable.
The yield was also decreasd remarkedly by the addition of EDTA, a chelating agent. And the yield was recovered by the addition of Fe ions to the same juice. YOSENA was assumed to be formed by the coagulation of particles containing the protein of chloroplasts by reactions between SH radicals, amino radicals and Fe ions.

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The results of comparison of gelatin sol mixed with agar to agar and gelatin individual case about the sol-gel transition and the rheological characteristics of the gel for mixed gelatin are sammarized as follows.
The gelation temperature of agar sol was 33°C and that of gelatin sol was about 14°C. The property of mixed sol for the gelation temperature resembles agar and the temperature was about 26-29°C.
The gelation time of mixed sol was much longer than individual case.
Transparency of an acid processed gelatin sol mixed with agar was remarkably lower than that of both agar and gelatin sols and it became turbid.
As for characteristics of fluidity at gelation temperature, the gelatin sol mixed with agar exhibited thixotropic property, while, the reference sol exhibited negative-thixotropic property.
The alkaline processed gelatin gels mixed with agar had a smaller rupture stress and a lower apparent elasticity in comparison with alkaline processed gelatin gels mixed with agar. The acid processed gelatin gels mixed with agar had a larger rupture stress and a higher apparent elasticity compared with agar and acid processed gelatin gel.
The amount ot syneresis for the acid processed gelatin gel mixed with agar was less and the gel was insoluble at room temperature.

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The bitter taste in the juice of Washington navel, Shamouti and Valencia oranges, grapefruit and natsudaidai harvested in the early or middle term of the year, usually increases after expression from the fruit. The delayed bitterness of the juice has been a problem in food processing.
The effects of preservatory methods on the bitter taste were examined. The samples were Banpeiyu fruits (Citrus grandis OSBECK) harvested in January at the Fruittree Research Institute of Kumamoto Prefecture.
The fruits were cut, and the juice was expressed and filtered through a double cheesecloth. The juice was Preserved at 5°C or 30°C, under aerobic or anaerobic condition. For the anaerobic condition, the juice in a test tube with a groundglass stopper was charged with nitrogen gas to replace the air and kept for 32 hours. Limonoid and naringin contents were determined by HPLC, and the bitter taste in the juice was evaluated by ranking test.
The results showed, with 5% significance, that there was more bitterness in the juice preserved under the aerobic condition at 30°C. Limonin content increased, but nomilin and obacunone contents did not changed.
The naringin content did not show any differences between samples kept under aerobic and anacrobic condition.
It may be concluded that the preservation conditions of the expressed juice affect the formation of limonin and increase the bitter taste.

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Dried Kanpyo was rehydrated with ultrasono-irradiation in search for rational rehydration methods. The effects of ultrasono-irradiation on physical properties and palatability of Kanpyo, and on color of the rehydration liquid were studied. The results were as follows;
Rehydration of ultrasono-irradiated Kanpyo led to an increase in its water volume absorbed and promoted decolorization of brown Kanpyo, as compared to the control untreated with irradiation. The best conditions for rehydration proved 5 to 10 minutes of ultrasono-irradiation and 8% sodium chloride solution for soaking liquid, decreasing in the stress value of its property of material, promoting penetration of seasonings, and resulting in superior taste. Under the above conditions, Kanpyo harvested in 1990 was decolored as well as the harvested in 1991, though the taste of the former was somewhat inferior to that of the latter. Rehydration of Kanpyo treated with ultrasono-irradiation enabled us not only to eliminate the rubbing procedure but also to achieve an effective decolorization.

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An investigation was made for clarifying the effect of milk on the physical properties of mixed gels using several kinds of gelatin and κ-carrageenan. The obtained results ware as follows.
1) The rupture stress of mixed gels using gelatins (alkali and acid processed gelatin) and carrageenan-B (the sulfur content is high) for the addition of milk was higher than that of the control mixed gel.
2) The rupture stress of mixed gels using acid processed gelatin and κ-carrageenan A-(the sulfur content is low) for the addition of milk was much higher than that of the mixed gel using κ-carrageenan-B.
3) The values of the rupture stress of mixed gels increased with the ascent of the pH for mixed solutions.
4) The rupture stress of mixed gels using alkali processed gelatin and κ-carrageenan-A decreased with the addition of calcium chloride, however that of the mixed gels using alkali processed gelatin and κ-carrageenan-B or acid processed gelatin and each κ-carrageenan increased.
5) The rupture stress of mixed gels using alkali processed gelatin and κ-carrageenan-B or acid processed gelatin and each κ-carrageenan decreased with the addition of casein.

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In this work we studied about thermal stability of chlorophyll in the powdered spinach (Chl) and chlorophyll in the powdered spinach included β-cyclodextrin (CD-Chl).
The results obtained were as follows:
1) The extent of heat decomposition of chlorophyll in CD-Chl was more stable than the Chl when the Chl and CD-Chl were heated in distilled water (pH5.6) at 60°C,80°C and 100°C.
2) The extent of heat decomposition of chlorophyll in CD-Chl was more stable than the Chl when the Chl and CD-Chl were heated in buffer of the acid area at 100°C.
3) Chlorophyll b was more stable than chlorophyll a when the Chl and CD-Chl were heated in distilled water (pH5.6)at 60°C and 80°C. Chlorophyll b was more stable than chlorophyll a when the Chl and CD-Chl were heated in distilled water(pH5.6)at 100°C up to 30min.
4) Chlorophyll a was more stable than chlorophyll b when the Chl and CD-Chl were heated at acidc area.
5) Chlorophyll b was more stable up to 30 min than chlorophyll a when the Chl was heated in buffer(pH6.0) which containing Na⁺, Ca²⁺ and Fe³⁺(10ppm) at 100°C.

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