Dried Shiitake mushroom (Lentinus edodes Sing.) is clasified roughly into Haruko, Harvested from January to June, and Akiko, harvested from July to December in Japan. Organoleptic differences between Haruko and Akiko were examined by 20 panels employing eight commercial varaeties. After cooking and seasoning with 1% salt, organoleptic evaluations on the appearance, flavor, taste, texture and overall were carried out by a modified paired comparison method and the scoring one. As the result, it was revealed that Haruko was more preferable in respect to overall than Akiko in any variety of Koshin group. However no significant differences were found between Haruko in Donko group excepting Akiko of Namidonko group was more preferable than its Haruko in respect to flavor and overall.

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Ethylene-treated banana fruit on the market is yellow and bright in peel color, but the taste of the pulp is poor in aroma and sweetness and is moreover considerably astringent. This report describes the method for improvement of the quality of banana fruit ripened in commercial practice.
Quality of ripe banana fruit put on a supermarket in Sakai City was examined from summer season to winter season. The peel color of the banana hardly differed through these seasons, but the sugar contents of pulp decreased as temperature lowered from summer to winter season. The elevating of ripening temperature to 30°C immediatelly after ethylene treatment for 24 hours at 20°C was effective to increase the sugar contents of pulp but depressed the degreening of peel. On the other hand, when green banana fruit was ripened for two days after ethylene treatment and kept at 30°C for 12 to 24 hours, the banana fruit had much higher sugar contents and the peel of the fruit was full yellow. Organoleptic test also showed that the short time treatment at elevated temperature (30°C) after ethylene treatment was effective to improve the quality of banana fruit which was insufficiently ripened at relatively low temperature by usual method.

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A simple and rapid analytical method of anthocyanin pigments in grapes and grape products was developed as follows. The pigments prepared by the basic lead acetate method were spotted on the cellulose thin-layers and separated by two dimensional chromatography. The individual pigments were identified by their locations on chromatogram and other qualitative tests, and determined by densitometry at 530nm. (1) Nineteen of the known anthocyanin pigments were arrayed on the two dimensional thin-layer chromatogram (the first solvent system, isobutanol-acetic acid-water, 8:2:3; the second solvent system, acetic acid-hydrochloric acid-water, 15:3:82), according to the number of sugars, organic acids and substituted groups (hydroxyl and methoxyl) in the B rings. (2) A linear relationship existed between the amounts (0-50μg) of pigments (malvidin-3, 5-diglucoside and peonidin-3, 5-diglucoside) and their densitometric readings, respectively. (3) Twenty anthocyanins from Concord grape juice and six anthocyanins (3-monoglucoside pigments only) from Hiro Hambrug grapes were characterized by this method.

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Characteristics of volatile components in the hydrolysates of Wasabia japonica, horseradish and mustard were investigated by using the head-space gas chromatography. R_g value, (peak area of ipropyl isothiocyanate/that of 3-butenyl isothiocyanate)×100, x value, (peak area of n-butyl isothiocyanate/that of 3-butenyl isothiocyanate)×100, and y value, (peak area of i-propyl isothiocyanate/that of sec-butyl isothiocyanate)×100 were calculated from the peak areas of volatile components detected. R_g value had the tendency of Wasabia japonica_??_mustard>horseradish, x value had Wasabia japonica >horseradish>mustard, and y value had mustard>Wasabia japonica>horseradish. Relation between R_g value, x value and y value derived from the mixture of two materials among above three materials and weight of material in the mixture showed the regular curves, respectively. Accordingly, the miximg ratio in the mixture of two materials could be determined by using above the regular curves. Various fat containing mustand flours showed also the regular R_g and y values, respectively.

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An enzyme having tyrosinase activity was extracted from the shells of Euphausia superba and partially purified by ammonium Sulfate fractionation, two stages of Sephadex G-200 gel filtration and DEAE-cellulose (0-0.6M). PAS (periodic acid-Schiff) positive reaction suggests that this enzyme is a glycoprotein, The enzyme was the most active at pH5.8 and 55°C for 4-tert-butylcatechol as substrate.Its activity was reduced to 85% during 10 min incubation at 50°C, pH7.0 but completely inactivated by 4 min at 70°C, indicating no thermo-stability. Metal ions were not necessary for the activation of the enzyme and iodoacetic acid did not prevent the activity even at 10mM. The enzyme, however, was inhibited by the following compound at the level of 10mM: KCN, 100%^*; diethyldithiocarbamate, 77%^*; NaN₃, 60%^*, so this enzyme was supposed to be Cu²⁺-enzyme like tyrosinase from mushroom. The activity was accelerated by the addition of NaCl to the reaction mixture and darkening in color of E. superba was depressed by immersing them into ascorbate(5 mM).

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The differences in total ergosterol contents and total fatty acid compositions of eight grades of dried Shiitake mushroom were investigated by gas-liquid chromatography. The results were obtained as follows: (1) Linoleic (71.3-80.7%) and palmitic (15.2-20.8%) acids were found to be predominant in samples, and oleic (1.8-3, 6%), stearic (0.6-1.4%), and myristic (0.2-0.7%) acids were also found in all the samples. There were no significant differences in the ratio of fatty acid compositions among the differentgrades of mushroom exeept Kuroko. (2) Total ergosterol contents were found in the ramge of 193-270mg% for dry weight. In order to show the distribution of ergosterol in two main parts of mushroom, their caps and stems were taken and their ergosterol contents were determined respectively. In the case of caps, ergosterol contents was 203-302mg%, while in the stems it was 137-158 mg%. The average value of ergosterol contents were 227mg% for the Donko type and 198mg% for the Koshin type.

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