Size distribution of tomato pulp was analyzed with several samples of commercial tomato juice and tomato catsup. The effects of size distribution of tomato pulp on the color of tomato products were examined by treatmellt of tomato pulp with a homogenizer, mixer, and ultrasonicator.
Remarkable differences of size distribution of tomato pulp were found in the tomato products. In the prodcts containing more fine particles, cells of tomato flesh were broken and lycopene uniformly dispersed. On the other hand, lycopene was present in granules inside the cells of tomato flesh in case of the products containing more coarse particles.
When tomato juice contained 0.5 to 1.0% tomato pulp, a quantitative correlation was observed between the amount of tomato pulp and the color intensity of tomato juice.
Color of tomato products was remarkably affected by color of tomato pulp, but not by color of tomato serum. The tomato pulp was the finer, the color of tomato juice was the fainter from bright red to whitish red. The cause for it was discussed on the basis of the experimental results.
Stability of lycopene was discussed on the presence inside or outside of the cells of tomatoflesh.

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Comparative studies were carried out on stability of uniformly dispersed lycopene in broken cells and of granular lycopene in intact cells of tomato pulp.
There was no difference between two types of lycopene under the conditions of storage at room temperature (20-37°C, 6 months), of heating (95, 110, 120, 130°C, 10 minutes), and of sunlight (5 months inside a window), lycopene decreased 2% by light and 5-15% by heating in either type.
Lycopene by heating in the presence of FeIII, CuII, or SnII ions was little more stable than that by heating without ions. However, no difference was found on stability of lycopene in both types.
The role of natural antioxidants in thmato was discussed.

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Among nineteen amino acids examined, tyrosine, methionine and tryptophan showed antioxidative activity on linoleic acid in aqueous system at pH 7.0 and 9.0, but at pH 5.0, all amino acids showed no remarkable inhibition of oxidation of linoleic acid.
After incubation of amino acids together with linoleic acid for 6 days, in three amino acids; (tyrosine, methionine and tryptophan, ) two spots were detected on a paper-chromatogram respectively. In case of methioine, one spot was methionine and other was methionine-sulfoxide which is considered to be formed from methionine by oxidative action of peroxide or radical formed during autoxidation of linoleic acid and its oxidative reaction velocity is more rapid in alkaline solution than in acidic one. Antioxidative activity of methionine on linoleic acid became stronger along With the increase of concentration of methionine from 0.1, to 1.5×1.0^-2 mol.
Although methionine-sulfoxide and methionine-sulfone had no influence on the stability of linoleic acid at 0.5×10^-2 mol. respectively, but both compounds showed antioxidative activity in 0.3×10^-2 mol. and pro-oxidative effect on linoleic acid in 1.0, 1.5×10^-2 mol.

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The edible part of a muskmelon fruit (Cucumis Melo L. var. reticulatus) contained D-glucose, D-fructose and sucrose as major free sugars, and arginine, histidine, lysine, tryptophan, aspartic acid, glutamic acid, alanine, valine, glycine, threonine, phenylalanine, isoleucine, leucine, methionine,

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Limonin and nomilin, the bitter principles of citrus, were extracted with chloroform and separated by a thin-layer chromatography. Each spot of limonin and nomilin was detected by spraying water and removed to test-tubes followed by dissolution with acetone. Each solution was determined by addition of p-dimethylaminobenzaldehyde solution and measurement of the solution at 550mμ.
This method is useful for determinination of limonin and nomilin respectively and for application in study of the problem of bitterness in orange juice.

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Gel strength, swellings power, syneresis and amylographic behaviour of potato-starch gels with nonionic surfactants were studied to know the effects of the surfactants on the aging of starch. All the surfactants employed in this investigation have an antistaling effect, namely, both of increase rate in the gel strength and decrease rate in the swelling power with time are lower than those of the control gel without surfactant. Especially, gel strength of the gels with more hydrophilic surfactants slowly increases.
The gels with hydrophilic surfactants, however, showed remarkable syneresis, which might suggest remarkable aging of starch.
Whereas, according to the amylographic behaviour at the time to prepare the sample gels in which syneresis appear easily, the gelatinization temperature is high and maximum viscosity is low. These results suggested that the interaction between the hydrophilic surfactants and the starch are fairly strong.
Inconsequence, it is seemed that the syneresis of starch gel is not necessarily caused by the aging, but caused by the decreased hydration power of the complex with hydrophilic surfactant and starch, and the strong hydrogen bond of intracomplex. At the same time, H-bonds of interstarch chain are disturbed by the occurrence of the H-bond of intracomplex, resulting in the restraint of the aging of starch.

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In order to improve the flavor of Haku soy sauce, addition of nucleic acids susceptible to be decomposed by phosphatase possibly contained in raw soy sauce was investigated.
Phosphatase activity in Haku soy sauce was completely inactivated by heat treatment at 80°C for ten minutes or at 85°C instantly.
Heat treatment did not give any significant change in the constituents, but resulted in browning to some extent, and sedimentation with some samples among the heated one.
A slight improvement was found in the smell, but not in the taste as the result of organoleptic test.

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The selected commercial polyphosphates which are approved as the food additives were used in the cooking process of four kinds of seaweeds of Gelidium species in order to find out ohe appropriate conditions for extraction of agar.
When the polyphosphates were used alone without sulfuric acid, the extraction of agar from Gelidium subcostatum was effectively promoted, but they were not so effective to Gelidium pacificum and Gelicium amansii as sulfuric acid. On the other hand, when the polyphosphates were used together whth sulfuric acid, the extractability of agar from Ge. amansii as well as from Ge. subcostatum was practically much improved.
With respect to gel strength (jelly strength in old term) of the extracted agar, polyphosphate containing 67-68% of P₂O₅ was better than the one containing 75% of P₂O₅.
(Note: The term 'jelly strength of agar' used elsewhere by the first author shall be amended as 'gel strength of agar', hereafter.)

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A method of quantitative determination of coal-tar dyes in candies was studied employing baker's yeast as adsorbent.
The presence of glucose (6%) markedly enhanced adsorption of dyes into cell of viable yeast, and the adsorbed dyes could be extracted with 0.5 N-NH₄OH. After neutralized and concentrated, resulting colored solution was developed on a thin-layer chromatogram, and then each band of dyes was scraped and extracted with water for colorimetry.

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