This study was designed to examine the effect of the thawing speed on the qualities of the food mainly consisted of gelatinized starch.
At first to know physical properties of starch gels that were frozen and thawed at the different speed, gel strength and viscosity were measured. Next to estimate the condition of gelatinized starch granules during the freeze-thaw process, gelatinization ratio of starch was measured with three methods turbidity methods, β-amylase pullulanase method and glucoamylase method.
The results of above estimations were as follows. Thawing speed, rater than freezing speed, affected the physical quality of starch gel. These changes more typically occured in the case of thawing slowly than rapidly. But those physical differences of starch gel after thawing couldn't be explained by the ratio of gelatinization.

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Fresh peppermints, spearmints and Japanesemints were stored at 2°C and 20°C, and the effect of packing with polyethylene bag (30μm thick. PE), polyethylene stretch film (12μm thick. PES) and polyvinyl chloride stretch film (16μm thick. PVCS) on the keeping quality of mints was studied.
The rate of weight loss was the greatest in PVCS package with all kinds of mints and at both temperatures. The freshness of mints in PVCS, rapidly deteriorated to the limit of saling after storage for 3days at 20°C while it was kept for 7days in PE and PES packages. At 2°C storage, the deteriorating rate of the quality was almost same among the three films and salable quality was kept for 20 days. Chlorophyll, ascorbic acid and free amino acid contents in all kinds of mints decreased during storage, but no difference of their changes among packaging films was observed.
The aroma evaluation score decreased with the progress of the storage time, and the rate was faster in PVCS and PE than in PES at both temperatures.
The decrease rate was higher in spearemints and markedly lower in Japanesemints.
It was concluded that the appearance and aroma of the mints should be the most important scale to evaluate the quality of fresh mints. PES was the most effective to keep the quality of mints the three kinds of films.

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Pigment from dried 6 marine algae (one species of green, three of brown and two of red algae) with acetone were investigated with antioxidative activity by the Warburg method. And at the same time, it was measurement with pH, absorption, thin layer chromatography and reducing power. The following results of this investigation were obtained :
1) Antioxidative activities of pigments from dried marine algae were shown with Aonori, Wakame, Asakusanori, Makonbu, Hijiki and Tengusa.
2) The yellow and blue absorption maxima of pigments with acetone were in the range of 425-419nm (Chlorophyll a, b) and 672-675nm (Chlorophyll a, b).
3) Pigments from dried marine algae with acetone were showed with green by green algae, yellow-green by brown algae and green, gray-green by red algae.
4) Thin layer chromatography (the solvent system was CHCl3 : MeOH : AcOH (90 : 10 : 1) of Silicagel-B5 of pigments from dried marine algae was found by 5 fractions in Wakame, 4 fractions in Aonori, Makonbu and Hijiki, and 3 fractions in Asakusanori and Tenguse.
5) Strongest antioxidative activities of fractions by thin layer chromatography were showed with higher front fraction in all pigments.

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