The relation between the composition of compounds induced from ATP and the freshness of raw fish was investigated. For the analyses of hypoxanthine, Hyp and IMP by using 5'-nucleotidase, nucleoside phosphorylase and xanthine oxidase were employed. The assay method was based on the separation of adenine, hypoxanthine, adenosine, inosine and nucleotides with ion exchage resin (Dowex 1×2 chloride type). The analysis of these substances in Canned fishes can be adopted as an index of their quality.

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The relation between the quality of canned fish and freshness of the raw material was examined employing hakuren (Hypothalmichthys, molitrix) saba (Peneumalophorus, japonicus)and and sanma (Cololabis, saira). As the indices for the freshness the ratios of the amounts of IMP, Ino and hypoxanthine to their total was adopted.
Remerkable decrease in the amount of ATP and increase in the contents of other nucleotides or nucleosides were taken place during the canning process of fishes.
During storage of the canned products at room temperature or 37°C for 6 months, no increase in the amounts of nucleotides were observed. A good correlation was observed between the IMP ratio in raw fish meats and the inspection scores given to the canned fishes.

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To elucidate the functional properties of Yuba-film formed from 11S and 7S globulins of soybean protein, Yuba-like films were prepared from the solution of CIF (11S) and crude 7S glubulin (7S), and the conditions of film formation, stress, strain and other properties of the films were studied.
The films from 11S were always stronger than those from 7S. Their stress and strain values varied with the changes of pH value of the solution, but in neutral range-normal condition of Yuba production, it was considered that 11S contributed to the strength of the film and 7s mainly to the hardness or brittleness.
Adding 2-mercaptoethanol, N-ethylmaleimide or urea in the protein solution, formed films decreased the strength remarkably. It was seemed that SH_??_SS reaction was concerned in the strength of films. Wrinkles peculiar to Yuba-film might have something to do with SS-linkage in the film proteins, because they appeared on 7S film, but not on 11S film, and they did also on the latter when it was prepared adding N-ethylmaleimide.

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The existence of the unknown substance (s) was suggested, which was entirely different from so-called "corrosion factors" such as nitrates, anthocyan pigments, cysteine and cystine and presumably plays the main role in the corrosion reaction in canned asparagus.
White asparagus was extracted with 75% ethanol and the fractions with ion exchange resins and ethereal extraction were examined as to the corrosion activities.
Both the sulfur-staining and corroding activities were found in the effluent from Dowex 50W×8 (H⁺ form). Further fractions with Amberlite IR-45 (OH^- form) treatment showed considerable activities of sulfur stain and corrosion.
By paper chromatograms of the hydrolyzates of the fractions, citric and tartaric acids were detected, which were not detected on paper even after extraction of the unhydrolyzed fraction with ether for 120 hours. The hydrolyzates and one of the ethereal extracts contained significant amount of glutamic acid.
It is assumed that at least one of the sulfur-staining and corroding factors in the fresh plants is the loose conjugate of glutamic acid and the organic acids. Results obtained from the fractionation studies also strongly indicates that sulfur containing carbohydrates and organic acids are involved in the sulfur-staining reaction of the internal wall of canned asparagus.

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From the boiling water extract of limed orange pee1 (Citrus Unshiu), white powder (PO) was obtained by means of alcohol precipitation, dialysis, removal of cation with ion exchange resin, and decolorization. Since PO was easily soluble in water and contained arabinose and galactose, it was presumed to be one of hemicellulose of comparatively low molecule. And it was found that this substance not only prevented the crystalization of hesperidin, but also precipitated tannin. Morevor when PO was 4 times as much as tanninc acid, this precipitate became remarkably soluble. These phenomenons agreed with the previously reported properties of methyl cellulose. By the addition of PO in canned mandarin orange, the transparency of syrup was preserved for a long time. Therefore, PO would be utilized as the natural prevention agent for the white turbidity in the syrup of canned mandarin orange.

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The absorbability of tannins was studied with a curdlan-type polysaccharide 13140 (PS), which was an insoluble β-1, 3-glucan produced by some mutant of Alcaligenes faecalis var. myxogenes and gelatinized by heating its water suspension. The absorption was completed within half an hour and was not affected by pH in the range of 3-8, but it was reduced with temperature increase and considerably with the presence of ethanol. The tannin removing ability of PS gel, which was made by heating together with tannin, was equal to that of ungelatinized PS. Since PS absorbed poorly low molecular polyphenolics but it absorbed considerably ordinary tannin present in fruits extracts, it is supposed that PS may be utilized as an astringency removing agent. The hardness of PS gel fell off remarkably with coexistence of tannin and therefore the care should be taken with the process of PS jelly.

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Antimicrobial effect of 25 kinds of food additives or natural materials were studied on boiled or unboiled noodles.
1. Antimicrobial effect of ethyl alcohol was increased proportionally with the relative amount of ethyl alcohol to water of noodle, and the growth of bacteria was completely inhibited when the relative amount of ethyl alcohol was over about 13% (V/V) of water in noodle (boiled or unboiled).
2. Antimicrobial effect on boiled or unboiled noodle was recognized when the concentration of glycine was over about 0.5% in noodle.
3. Antimicrobial effect of glycine or ethyl alcohol on boiled noodle was increased by the Steam-treatment.
4. Antimicrobial effects of acetic and DL-malic acids were superior among the organic acids.
5. Antimicrobial effects of above mentioned and other materials were shown as "index of antimicrobial effect."
6. Antimicrobial effect of combined treatment of these materials was equal to the sum of the effects of each materials.

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Post harvest changes in the quality and some components especially organic acids of the cucumbers (variety, Hikari No.3) stored under several conditions varying the temperature and atmosphere were investigated. The quality was evaluated on the 12th and 19th day of storage. The analyses of organic acids in cucumbers were carried out by the simplified method employing an automatic organic acid analyser using the silica gel column chromatography. The decay of the cucumbers was accelerated by the conditions of high CO₂ and low humidity, and the injury was also caused by the same condition and low temperature. Under the conditions of low temperature or high CO₂, the pH value was fairy elevated and the content of ascorbic acid was distinctively lowered. After the storage under the conditions of low temperature, low humidity or high CO₂, malic acid which was dominant among the organic acids in cucumber was decreased, whereas citric, fumaric and succinic acid were increased. Furthermore α-ketoglutaric and pyruvic acid increased under high CO₂ condition.

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