The effects of nitrate on the color development and the reduction of nitrate to nitrite in meats were studied.
(1) During the short curing (1-7 days), the reduction of nitrate to nitrite by nitrate-reducing bacteria is so little that it is diffcult to develop cooked cured meat color in meats.
(2) Nitrate was decomposed during the short curing more slowly in the presence of nitrite than in the absence of nitrite. In this case, there is little effect of nitrate on the color development in meats.
(3) Most nitrate-reducing bacteria in meats were killed by cooking for 50 minutes at 63°C.
Nitrate has usually been used in cure with higher concentration (0.1-0.2% for meats) in the presense of nitrite in Japan. From the results described above, however, it can be considered that the desirable levels of nitrate are almost the same as nitrite (approximately 0.02% for meats) in the short curing processing. (Received July 27, 1970)

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The transmission colors of black tea infusion, the theaflavin fraction and the thearubigin fraction extracted from black tea infusion were measured by the Hunter color meter. The theaflavin and the thearubigin contents in black tea infusion were determined by the Roberts' method.
The Hunter L, a, and b values of black tea infusions showed highly significant correlations to those of the thearubigin fractions extracted from black teas, and rather lower correlations to those of the theaflavin fractions.
The theafiavin contents in black tea infusions did not have high correlations to the Hunter values of black tea infusions, and the thearubigin contents had rather higher correlations. From these results, it was recognized that the color of black tea infusion was effected by the color of the thearubigin fraction, which has highly relation to reddish color of black tea infusion, and the theaflaviln fraction did not have significant relation to the color of black tea infusion determined by the Hunter color meter.
There were highly correlations between the theaflavin contents and the Hunter values of the theaflavin fractions extracted from black tea infusions. But there were rather lower corelations between the thearubigin fractions and the Hunter a and b values of the thearubigin fractions and there was only corelation between the formers and the Hunter L values.

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When faecal bacteria of hens were inoculated in bacteria-free raw and frozen-thawed whole liquid egg and incubated at 35°, bacteria began to grow after 1 hr's lag period.
While bacterial population tended to decrease when the faecal bacteria of hens were inoculated in bacteria-free raw egg white and incubated at 35°. But bacterial population did not decrease when the faecal bacteria were inoculated in the frozen-thawed egg white after storage 1-6 months at -20°. The decrease of antimicrobial activity in the frozen-thawed egg white was assumed to be due to the decrease of the lytic activity.
The population of the inoculated faecal bacteria of hens in the whole liquid egg, stored at -5°--10° for 2 months, became smaller than that stored at -20°. Coliform bacteria seemed to be more sensitive than other bacteria for freezing damage. The population of Escherichia coli in egg white after freezing storage tended to be smaller than in whole liquid egg.
The population of bacteria, which contaminated the egg during process, in whole liquid egg containing 5-20% sucrose did not decrease after storage even at -5°--8°, because of the protection to the freezing damage, while the population in whole liquid egg decreased remarkably by the addition of 2-3% NaCl.

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Kaki-shibu, the astringent extract from persimmon fruits which is used for the clarification of sake (rice wine), emits a kind of foul smell. In this study, the sources of this smell have been researched. The volatile organic acid was isolated by steam distillation and ether extraction. Eighteen acids, i.e. formic, acetic, propionic, butyric, isovaleric, valeric, caproic, enathic, pelargonic, and unknowns, were detected from the extract by the gas chromatography. Commercial kaki-shibu contained about 2% of total acid and most of it was volatile. Acetic acid was about 60%, propionic acid about 18%, and butyric acid about 4% of volatile acid. It was found that the volatile acids were produced from sugar in the press juice of persimmon fruits by the organic acid fermentation during early storage period.

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"Hata-hata Sushi" (in Akita Prefecture) is made of vinegared "Hata-hata" (Arctoscopus japonicus), cooked rice, "Koji", fresh carrot, fresh turnip and salt.
The variation of organic acids in the above mentioned materials and the fish meat in "Hatahata Sushi" was measured by means of a partition chromatography using silica gel. 13 kinds of organic acids were confirmed, of which main organic acids were acetic, lactic, pyruvic, furmaric, malic and citric acids.

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As the precipitation of tannin with methyl cellulose (MC) was full of interest, factors affecting the ratio of removed tannin to original one were studied. The precipitation was scarcely affected by pH in neutral and acid solution. The maximum precipitation ratio was found in the case where MC was double amount of tannin, and when MC rised or fell from this case, the ratio decreased. The ratio was also reduced with the rise of temperature and with the presence of inorganic salt, sugar, and especially alcohol. Among many high molecular carbohydrates and their derivatives, it was found that MC had exceptionally strong activity, while ordinary cellulose showed slight activity. It was presumed that the precipitation was mainly caused by hydrogen bond between hydroxyl groups of tannin and methyl ether bonds of MC. Because precipitation with MC was seen only for high molecular tannin but not for low molecular polyphennolics, such as catechin, chlorogenic acid, and anthocyanin, it was supposed that MC would be utilized for removing of astringency from fruit or vegetable juices.

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It was usually explained that the removal of astringency resulted from the condensation of tannin with acetoaldehyde produced by alcholdehydrogenase and so the distinction between astringent and non-astringent persimmon fruits was mainly under the control of alcholdehydrogenase activity. But it also expected that tannin of non-astringent persimmon was different from that of astringent one. Therefore, the components of tannin in the fruits of many varieties of persimmon, were studied. Unknown polyphenolic compound isolated from astringent fruits was identified with β-D-glucogallin (β-1-O-galloyl-D-glucose). From the patterns of the distribution of low molecular polyphenolics, paper chromatograms were divided into three classes, i.e. astringent, non-astringent, and intermediate type. High molecular tannin of non-astringent varieties contained more leucoanthocyanin and leucocyanidin than that of astringent varieties. These results were just as expected. Morecover, the quantitative and qualitative changes of polyphenolic compounds during the ripening. of fruits were studied.

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