Bacillus sp. 11-4 isolated from Vietnamese fish sauce was slightly halophilic and produced some extracellular protease. The proteases from Bacillus sp. 11-4 were purified by ion-exchange chromatography and gel filtration. The major extracellular protease (Protease I) from Bacillus sp. 11-4 was neutral protease, which was 33.5 kDa and pI 7.4. The protease I required Ca ion to expression protease activity. As protease activity was inhivited with chelating reagents such as EDTA and o-phenanthroline, protease I was metallo protease. The protease I that hydrolyzed native collagen, azocoll and specific substrate for collagenase such as FALGPA and z-Gly-Pro-Leu-Gly-Pro·H₂O·AcOH was collagenase. The protease I had caseinolytic activity. A molecular mass of protease I differed from other collagenase.

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Starch is mobilized as a source of sugar during low-temperature sweetening or sprouting by enzymatic digestion. Resulting damage on starch granules by enzymatic attack should be measurable by differential scanning calorimetry. Starch granules were isolated from 'Danshaku' potato tubers after 0, 22 and 45 days of storage at 10 and 0°C. The samples were heated from 30 to 90°C in a starch : water solution (3 mg : 10μe) at several rates (1 to 15°C/min) to determine kinetic constants of gelatinization. Starch gelatinization in tubers from both treatments occurred at lower temperatures during storage, indicating a reduction in starch stability with time. Lower activation energy for amorphous swelling and reduced temperature breakpoints of stored tubers also indicated reduced structural stability. Morphology changed with storage time in both treatments ; surface irregularities were observed by scanning electron microscopy, possibly due to resynthesised starch deposited on original granules or inner granules revealed as starch was mobilized by enzymatic action.

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Removal of insoluble solids as a means for reducing pink discoloration in lychee juice was investigated. The occurrence of pink discoloration in lychee juice and its concentrate is perceived as poor quality. Experimental results indicated that the precursor of the pink compound was bound to the insoluble solids in the juice. The pink color with a maximum absorption of 533 nm developed during the heating of the precursor. The color compound was a leucocyanidin with cyanidin as the only aglycone component. The discoloration rate was higher at lower pH value. The degree of discoloration of the lychee juice concentrate could be effectively reduced with the removal of the insoluble solids by filtration or centrifugation before concentration.

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Lipid content and fatty acid compositions were examined for 26 species of wild and cultured puffer fish imported from Korea, China and Bangladesh and wild puffer fish caught in Japan. Them, one potential application of the meat of this fish was considered. Total lipid content of wild puffer fish meat was found to be somewhat less compared to cultured puffer fish. It is presumed that those differences are clearly connected to the compositions of fatty acids depending on the biotic factors for feed in, because wild puffer fish are migrating type of fish. No differences regarding specific compositions in fatty acids were recognized. In fatty acid compositions of cultured puffer fish C18-2n6 content showed markedly high.

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