Experiments on the radiation disinfestation of rice and the organoleptic evaluation of rice irradiated by the silo type grain irradiator were conducted. This irradiator was designed as a pilot scale to obtain the data for the industrial grain irradiator. The irradiator has the Co-60 rod source of 2771 Ci in the center tube and three annular cylindrical irradiation fields around the source. The radiation dose is controlled by regulating the shutting time and slit width of the annulus gate valves.
In the disinfestation test, the adults, eggs, larvae and pupae of rice weevil, Sitophilus zeamais, which is one of the main cereal insects in Japan, were irradiated with the rice at the dose of 8-21 krad. The mortality of adults was about 85% at 7 days after irradiation and almost 100% at 21 days. The emergence of adult from eggs, larvae and pupae was also prevented by irradiation. The organoleptic properties in appearance, odor, taste, cohesiveness, hardness and over-all were evaluated by comparing non-irradiated rice with irradiated one. A slight organoleptic deterioration of cohesiveness was detected on the irradiated sample immediately after irradiation. But there are no significant differences on the sample stored for 3 months after irradiation.

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Separated cells from pulp of banana, strawberry or melon were obteined using pectinase. When butyl alcolol and acids(acetic or butyric)were added to these cells, esters were produced from separated mesocarp cells of strawberry and melon, but mesocarp cells of banana did not produce the esters. Vasculer tissue separated from banana pulp showed a strong capacity of esterification in contrast to mesocarp cells. From microscopic view, vasculer bundle was accompanied with bigger cells than mesocarp cells. Protoplasts from strawberry indicated also the esterification in the presence of butyl alcohol and butyrate. Addition of alcohol to separated cells or slices of these fruits indicated slightly acidic optimum peak(pH 5. 5)for esterification. The addition of acid besides alcohol shifted pH optimum from 5.5 to 6.5.

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The influences of storage temperature(10-40°C)and moisture content(2-8%)on browning of the spray-dried preparation from Citrus unshiu juice were examined.
As the storage temperature and moisture content became higher, the browning rate of the preparation increased exponentially.
The increase in browning rate of the preparation was apt to be great particularly when the storage temperature was elevated beyond 30°C.

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To elucidate the feasibility of using gamma-irradiation for the extension of shelf life of Citrus Unshiu ("Satsuma" orange), organoleptic properties, browning of peel and rotting by fungi of irradiated fruits during storage were investigated.
When the fruits were irradiated with 50 krad and tested immediately after irradiation, off-flavor was detected in flesh of fruits. However, after 7 days' storage at 4°C, there were no statistical differences in the qualities as judged by the taste panel members. Off-flavor of fruits irradiated with 200 krad also decreased during storage at low temperature.
Radiation dose of 50 krad was not sufficient to prevent development of microorganisms causing spoilage of fruits, but 150 to 200 krad were effective to control the rate of development of blue and green mold. The fruits irradiated with 200 krad exhibited the browning of peel during storage. There were no effects of dose rate in a range of 5-500 krad/hr on the peel browning and rotting during storage at 3°C for 3 months. No growth of fungi was detected in the fruits which were irradiated with 200 krad followed by storage at 3°C for 3 months. However, when the irradiated fruits were stored at room temperature for one week after storage at 3°C for 3 months, rotting by fungi and browning of peel increased, and in addition, extreme softening and shrinking of peel were observed.

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Interaction between soy sauce (brewed naturally) and cottonseed oil was investigated in the system consisting of soy sauce powder, cottonseed oil and water.
Viscographic tests revealed that oil solubilization occurred under some specific conditions of composition in the system and agitation. The solubilized mixture was non-emulsive, and oil droplets were not observed microscopically in the mixture. Solubilization of the mixture was quantitatively expressed as hardness, F (c), and adhesiveness, F (a), measured by a Rheo Meter. These values were paralleled to turbidity determined by a spectrophotometer of the mixture diluted with water.
The aqueous solution containing about 70% (w/w) of soy sauce powder stably solubilized cottonseed oil up to O.8 volume of the aqueous solution.

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This paper describes some behavior of incorporated oxalate into pulp-homogenate.
Radioactivity of alcoholic extraction from green banana homogenate which was administrated sodium oxalate-¹⁴C gradually decreased. On the other hand, radioactivity of the extraction from yellow banana homogenate disappeared within short time.
Most of the radioactivity remained in anionic fraction and a small amount of radioactivity was found in cationic and neutral fraction. Distribution of radioactivity on silica gel chromatogram from green banana showed rapid disappearance of oxalate and corresponding increase of a acidic fraction that was eluted with 2N formic acid, while yellow banana did not show such phenomena.
Decarboxylation of oxalate by yellow banana was mainly due to subcellular particles. Relatively high activity of decarboxylation was obtained between pH 2.5 to 5.5 with optimum pH at 3.2.
Stoichiometric observation of decarboxylation of oxalate showed one volume of carbon dioxide evolution and a half of oxygen absorption. The fact indicates that the enzyme in banana pulp was oxalate oxidase (EC. 1. 2. 3. 4).

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Glucoamylase(E.C 3. 2. 1. 3., α-1, 4-glucan glucohydrolase)was immobilized in a bead shape (0.5-1mm diameter) by radiopolymerization method under the frozen temperature(-86°C). The characteristics of the immobilized enzyme were investigated and the enzyme column was operated continuously, 1). The optimum reaction pH was 4.7 for native enzyme and 4.2 for immobilized one. 2). The smallest bead had the highest retained activity (67.5%) when soluble starch (Merck, Zulkowsky)was used as a substrate. 3). There was no big differences in the optimum reaction temperature between native and immobilized glucoamylase. 4). Km value of immobilized enzyme was 2.6 times(maltose as a substrate)or 7.3 times(soluble starch, Merck for analysis, as asubstrate)higher than that of native enzyme. 5). Liquified starch(5.5% solution) was passed through the column (flow rate SV 2.3) in which bead shaped glucoamylase was packed and hydrolyzed to 94%.
At the fixed flow rate (SV 1.36), starch solution was hydrolyzed (over 90%) continuously up to 60 hours.

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A simple checking method of quality of 'Wasabi' powder was investigated employing head space technique.
R_g values and R_i values, ratio of the peak area of allyl iso-thiocyanate to that of internal stanndard, n-propanol, were culculated as the standard ones of checking. R_g values of mustard flours were larger than these vaiues of horse-radish flours. However, R_i values of the former were smaller than these values of the latter, reversely. R_g and R_i values were calculated about 'Wasabi' powders which were consisted of horse-radish and mustard flour with unknown mixing ratio, and these ratios in these powders were estimated from the standard relation curves.

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Volatne components in the hydrolysate of ground Wasabia japonica were investigated by gas chromatography using the head space technique.
The linear relation was obtained between R_i value and the weight of Wasabia japonica. Since the same relation was estimated between the R_i value and the concentration of authentic allyl isothiocyanate, a simple quantitative determination of allyl isothioyanate in Wasabia japonica will be possible by this technique. R_i value of each Wasabia japonica root were changable. However, R_g values were all under 50%, and almost unchangeable among the roots.

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