A callus was induced from the root of seedlings of Hiproly barley in White's medium containing 20mg/l of 2, 4-dichlorophenoxyacetic acid (2, 4-D). Kinetin did not stimulate the growth of the callus. The callus grew well in White's medium containing 2mg/l of 2, 4-D at 26°C in the dark. Sucrose was a better carbon source than glucose, fructoes, or mannitol in agar solidified cultures. The addition of fructose or mannitol to the basal medium with sucrose stimulated growth of the callus. Malto extract, or ammonium citrate also stimulated its growth. The addition of biotin stimulated growth effectively. The callus grew rapidly and constantly in modified White's medium containing 2mg/l of 2, 4-D, 1% fructose, 3% sucrose and 100μg/l of biotin.

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Most vinegars today are produced rapidly by using a cavitator. They have a harsh odor and stimulative taste during the early period of storage. As they age, their odor and taste become very mild. This study examines this interesting phenomenon from the physicochemical point of view. Changes of the partial pressure and concentration of acetic acid in the vapor phase of vinegars storaged for 8 years were investigated. The partial vapor pressure was precisely measured in the presence of various concentrations of ethanol, ethyl acetate and other chemicals. The partial vapor pressure was reduced with the period of storage. The acetic acid concentration of the vinegar's vapor also decreased in proportion to the length of storage. The changes induced by aging were independent of minor chemical components, whose effects were investigated throughout this study. These findings suggested a specific liquid state occurred in aged vinegars, i. e., formation of a stable molecular cluster which decreased the monomeric acetic acid molecule.

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The effects of ethanol concentration, pH and temperature on the formation of ethyl esters (ethyl acetate, ethyl lactate, diethyl esters of succinic, malic and tartaric acids) were investigated in model solutions and wines. Greater esterification of the acids was found at higher ethanol concentration, lower pH and higher temperature, and the efficacy of these factors was higher in esterification of dibasic acids than monobasic acids. Since the estimated values for activation energy and Q₁₀ of ester formation were 3.8 to 19.8 kcal/mol and 1.2 to 3.1, respectively at 5 to 30°C, ester formation in wine was considered to be chemical reaction. A high correlation was observed between aging time and the ratio of diethyl succinate-to-monoethyl succinate, and the ratio was regarded as an indication of aging. The correlation coefficients for white and red wines were 0.884 and 0.868, respectively. In conclusion, wine flavor was improved by esterification of the main organic acids during aging under suitable temperature and time.

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Selenium contained in milk casein (vitamin-free), soybean proteins (concentrate and isolate) and skipjack (dried strips) was fluorometrically determined after digestion with nitric and perchloric acids and was examined for the availability in rats. The selenium contents in these protein sources ranged on dry weight basis from 0.34 to 0.60μg/g protein, except for dried skipjack strips, which contained 3.4μg Se/g protein. On feeding the rats with the test diet (15% protein level), the hepatic selenium level and glutathione peroxidase activity responded, within a limit of saturation, to dietary selenium levels. The availability of dietary selenium was found to be about 50% for the skipjack diet and not less than 75% for the other protein diets. This was assessed by measuring the dietary intake and fecal output by direct analysis and by making a correction for metabolic, obligatory fecal loss (0.04μg Se/day/rat). The digestibility of selenium-bearing protein per se may be an additional, important factor affecting the overall biological activity of the selenium associated with these proteins.

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A simple and accurate method is described for gas chromatographic determination of thiabendazole in fruits. Thiabendazole was extracted with dichloromethane. In order to clean up the extract, a column packed with Sephadex LH-20 was employed. Thiabendazole was separated from the extract and injected onto a FPD-gas chromatograph equipped with a column of 10% OV-351 coated on Gas Chrom Q (60_??_80 mesh, 3mm id×50cm). Phenothiadine was used as an internal standard for accurate determination. The measuring limit of determination was 0.01ppm. Good recovery was obtained in the added-recovery experiments. The simplicity and convenience of the method make it suitable for routine analysis.
In a market survey, thiabendazole was detected in almost all imported citrus fruits. It was not detected in bananas and domestic citrus fruits.

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When egg yolk was frozen and stored above -10°C for 72 hr and then thawed, its fluidity was retained. Differential scanning calorimetry (DSC) analysis indicated that the unfrozen water in yolk was not reduced to the extent of unfreezable water (0.16g/g solid) at the temperature between -5° to -10°C. On the other hand, the extent of gelation gradually increased with storage during 24 hr at -15°C and -20°C. The temperature-time curve in freezing and DSC analysis of the yolk indicated that the transition of water, other than the unfreezable water, to ice was completed in a few hours under these conditions. In addition, unfrozen water of the yolk was not affected by freezing temperature between -11°C and -44°C and was found to be 0.15_??_0.25g/g solid.
Although the fluidity of the yolk was retained in the freeze-stored samples at -60°C, gelation occurred within a few hours when it was subsequently stored at -20°C. It was assumed that the gelation was caused by the reduction of unfrozen water to the level of unfreezable water during ice formation and, furthermore, by partial removal of ice between the lipoprotein molecules depending on the increase of crystal size of the ice due to the repetition of melting and recrystallization of ice during freezing storage.

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