The effects of antioxidants on carotenoid (lycopene) during T.L.C. procedure were studied. In the course of T.L.C. procedure in the air, carotenoids were rapidly oxidized ahd discoloured. BHT was the most effective antioxidant for lycopene. Antioxidant was required to be present in solvent during T.L.C. procedure. Further satisfactory antioxidation effect was obtained provided all the procedures were worked out in nitrogen atmosphere. Optimum concentration of BHT for protection of lycopene oxidation was 1-2% in the solvent.

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In order to investigate whether the green pigments of canned oysters have a porphyrin ring such as chlorophyll or not, the physico-chemical property of the oxidation products of the green pigments of canned oysters was compared with that of the oxidation products of copper chlorophyllin which was oxidized by chromium trioxide-sulfuric acid mixture.
The oxidation products of the green pigments of canned oysters and copper chlorophyllin could be separated into four components respectively. The results of the chemical reaction, absorption spectra, thin layer chromatographies, solubility examination, infra-red spectra and micro elemental analysis of the former showed the same behaviour as those of the latter indicating that the green pigments of canned oysters have a porphyrin ring.

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There is a need for a rapid, simple and practical method for determing tannin in Kaki-shibu. As the result of analysis on non-tannin components, the existence of the considerable amount of D-mannitol was proved. The exact tannin content was determined by a hide powder method resulting in higher content than those obtained with Folin-Denis method or Lowenthal method. It was also observed that the adsorption of tannin to hide powder decreased according to the enlargement of molecular of tannin.
The method developed is based on the principle that tannin content is in propotion to the difference of refractive indexes between original Kaki-shibu and tannin removed one. As the tannin removing reagent, 7% polyethyleneglycol solution, which consists of equal amount of MW 1, 000 and 2, 000 of polyethyleneglycol is used. The refractive index is indicated as 0Bx by the use of a hand refractometer. This method therefore is called Brix method.
The procedure of Brix method is as follows; To 5 ml of Kaki-shibu is added 2ml of water and ⁰Bx of this mixture is A. Then 2ml of 7% polyethyleneglycol solution is added to 5ml of Kaki-shibu and mixed vigorusly. After standing for about 10min., it is centrifuged and ⁰Bx of the supernatant is B. The tannin content is given by 0.93 (A-B)%. This method is also applied to the rapid determination of other tannin extracts.

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A method for the non-destructive measurement of total residual gases in retortable pouches was described. The method was based on a bouyancy principle and Boyles' law as follows:
Volume of residual gases in cc=Pressure at neutral bouyancy×Wt. in water in grams/Atmospheric pressure-Pressure at neutral bouyancy
A close correlation was observed between the volume of enclosed gases determined experimentally and that of calculated ones, especially when the weight of pouches in water ranged from 2 grams to 10 grams. On the contrary, Vacuumizing operations for determining pressure at neutral bouyancy interfered the accurate measurement of residual gases. And this appeared to be occurred by the vaporization of dissolved gases in food.
It was concluded that the present method has a good accuracy compared with the destructive method and the volume of residual gases in commercial food in retortable pouches is able to be determined rapidly by the present method.

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To the solution of soybean cold insoluble fraction, sodium carbonate was added until the pH of protein solution became 10.5. And the mixture was warmed at 60°C in a water bath, aerating continuously by a compresser. The pH and temperature in the above condition are relatively critical in denaturation of soybean protein. The treated protein was scarcely recognized any changes of structural conformation except deamidation by means of ultracentrifugation and amino acid analysis. Comparing original protein, the treated one is more soluble in neutral or a little acidic range.

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Feasibility of zone electrophoretic method using cellulose acetate film as a supporting medium was examined for species differentiation of some commercially important fish in kinship each other, since a need has arisen for proving a case of mislabling of fish, particularly in frozen forms. So far tested, cellulose acetate strips prepared by Courtlauds Limited of Conventry for Oxoid Ltd. gave a more satisfactory separation of soluble muscle protein than those of Separax. Procedure suggested in the present paper starts with one minute's blending of flesh portion of fish with equal volume of veronal buffer (pH 8.6, I=0.05), then centrifuge at 5, 000 rpm after 30 minutes, extraction in a refrigerator at 5°C and supernatant thus obtained is subjected to the electrophoresis under a current of 0.6mA/cm from 30 to 60 minutes. The zone development is made by staining each strip with 0.8% solution of Ponceau 3R for one minute with subsequent washing with 5% acetic acid for six minutes in order to remove unfixed dye on the strip. The species studied covered gurnard, yellowtail, mackerel, horse mackerel, plaice, cod, Alaska pollack, shrimps, and queen crab. Reproducible patterns from these examinations were considered to be employed to identify the species in question. Interesting finding to note was a close similarity in the patterns between two queen crabs, which have been regardedtaxonomically different species.

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