Effects of energy and current of electron-beams and synergistic effect of heat and radiation on a growth of fungi and a browning of peel were investigated to extend shelf-life of Citrus Unshiu ("Satsuma" orange). The fruits were irradiated with a surface dose of 200krad by various energies of electrons(0.2-1.5MeV), and then stored at 3°C for 3 months.
Percent of browned fruit in the fruits irradiated by 0.2MeV electrons was almost the same as that in the unirradiated ones. However, if the fruits were irradiated by energies of more than 0.5MeV, the browning of peel increased with increasing energy of electrons. The browning seems to depend on a dose absorbed only in peel, but not to depend on a total dose absorbed in fruit. When the fruits were stored at 3°C for 3 months followed by storage at room temperature (16-25°C) for one week, the effective growth inhibition of fungi was observed on the fruits irradiated by 0.5 MeV electrons. On the fruits irradiated with 0.1-1.0mA of beam current by 0.5 MeV electrons, increasing current tended to inhibit the growth of fungi. But the browning of peel was unaffected by beam current. Heat and radiation combination increased the browning of peel and the growth of fungi during storage.

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The adsorbed fraction(Aa) and nomadsorbed fraction(Ab) from the Sendai-miso extract have been isolated by ultrafiltration and ion-exckange resin. Subsequently, 3-deoxyglucosone-free fraction(Ab')was separated from Ab. Changes occurred during the process of heating, mainly in voiatile carbonyl preuction, have been studied.
The ratio of volatile carbonyl amounts obtained from Aa and Ab by heating was about 3:2. Aldehyde and furfural were formed from the adsorbed fraction and the nonadsorbed fractions, respectively.
Ab differed from Ab' in the amount of volatile carbonyl production, and in the development of the characteristic heated flavor. In the sample of(Aa+Ab'), the change of 3-deoxyglucosone from accumulation to degradation was followed by the furfural formation.
These results showed the important contribution of 3-deoxyglucosone-containing fraction(Ac) as the intermediates related to the volatile carbonyl compound and the maltol-1ike flavor componnd in miso.

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Gamma irradiation of Kamaboko (a kind of fish jelly products) has been investigated to extend their shelf-life. In this study, the dose distribution in a 14×27×38cm package of Kamaboko was measured with a Fricke dosimeter, to elucidate the better irradiation conditions. The ratios of the absorbed dose in Kamaboko (D_K) to the dose in irradiation field (D_F) were almost same at the dose rate of 2×10⁵, 5×10⁴ and 1×10⁴rad/hr. When the package of 14cm thickness was irradiated at the dose rate of 3×10⁵rad/hr and reversed at half dose, the dose uniformity ratio was 1.16 in depth. The ratio was 1.11 in vertical. Therefore, the overall dose uniformity ratio was calculated from above these values as approximately 1.29. In the case of Kamaboko with wrapping film and wooden plate, smaller dose uniformity ratio in depth was obtained as 1.12. The dose uniformity ratio in the package of Kamaboko calculated from the values DK/DF almost agreed with the observed ones.

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Calcium ions(0-300ppm)were added to canned white-pulp peaches(Nunome-wase, Mishima-hakuto and Okubo) in order to keep good quality and to prevent softening or breakdown of pulp texture during transportation.
It was observed that the drained weight, firmness of pulp, and calcium content in alcohol insoluble solids(AIS)from peach pulp increased in almost direct proportion to the concentration of the added calcium ions. Water-soluble pectin in AIS showed a tendency to decrease, whereas both oxalate-soluble and hydrochloric acid-soluble pectins increased with increasing calcium content. Shaking with an automatic shaker for 18hrs, the calcium-added peach pulp showed no breakdown, but in peaches without calcium, breakdown was observed among about one-third of the tested pulp.

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It was found that major inorganic compound in fishes is not tricalcium phosphate as had been geuerally assumed but is other type of compound which was identified as apatite Ca₅(PO₄)₃ (F, OH). Usually apatite is a solid solution of fluorapatite Ca₅(PO₄)₃ F and hydroxyapatite Ca₅(PO₄)₃ (OH).
Relatively big fishes as tuna contain nearly stoichiometric apatite and small fishes as crucian, saurel and sardine contain apatite with phosphorus in excess. A part of apatite containing phosphorus in excess was gradually decomposed during heating above 600°C to obtain ash, resulting in formation of β-tricalcium phosphate and β-calcium pyrophosphate.
It was found that amount of ash in fishes did not reach constant at 500-600°C, usual temperature based on the official method. Temperature required for obtaining constant amount of ash depended mainly on Ca/P atomic ratio in fishes; it was 900°C with the ratio of about 1.65, 1000°C with the ratio of about 1.5 and higher temperature than 1000°C with the ratio of about 1.25 or smaller.
On heating fishes containing salt, sodium chloride was reacted with a portion of apatite at 1000°C to form β-rehenanite, resulting in volatilization of hydrogen chloride.

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Two Japanese Black Cattles were slaughtered according to normal procedure. Each carcass was stored for 2 days at 0±1°C, and then loins were removed. After storage for 1 day at 0±1°C, about 500g of beef cuts were prepared from the whole loins shortly before film-packaging. Film-packaged beef cuts were stored at 0±1°C for 5 months, and the changes in bacterial counts and volatile basic nitrogen were investigated at various storages intervals. Films used were vinylidene chloride type film (VC) and nylon-laminated polyethylene (NP).
As the results, one and two months appeared to be a reasonable period for the storage of beef cuts packaged in VC and NP, respectively.

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Pungent components in 8 groups of Wasabia japonica were examined by head-space technique. R_i values of the samples varied between 123.0-194.3% with little difference between each group. The different R_g values were shown in each group. and the greatest was that in Mazuma and the smallest was that in Sanpo and Shimane No.3(nutrition).
The weight of isothiocyanates was determined by GADAMER'S method, NAGASHIMA'S method, and head-space technique. The contents calculated by the head-space technique closely resembled to those obtained by GADAMER'S method. It was concluded that the head-space technique was applicable as a simple quantitative method for determination of allyl isothiocyanate and the other pungent components.

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