The protective effect of an oxygen absorber (commercial name: AgelessZ-50, produced by Mitsubishi Gas Chemical Co.) on oxidation of lipids in roasted and ground soybean ("Kinako" in Japanese) stored at different temperatures (25°C, 5°C and -25°C) for 150 days was investigated. In application of the oxygen absorber, "Kinako" was preserved in an airtight film bag with the oxygen absorber (Oxygen-free). The results obtained were as follows. (1) In the case of control, acid value, peroxide value and carbonyl value of total lipids extracted from "Kinako" increased at each stored temperature, but iodine value decreased. The changes mentioned above were more remarkable as storage temperature was higher. However, in the case of oxygen-free, the changes of the above oxidation indexes of total lipids were slightly observed. (2) The ratio (wt%) of compound lipid fraction in the total lipids of "Kinako" stored at 25°C and 5°C decreased, but the ratio of neutral lipid fraction increased as storage period was longer in the case of control. However, in the case of oxygen-free, the above changes were not observed at three storage temperatures. (3) In the case of control, the ratio of triacylglycerol in neutral lipid fraction and the ratios of phosphatidylcholine and phosphatidylethanolamine in compound lipid fraction of "Kinako" showed a tendency of decrease as compared with other lipid classes. On the other hand, in the case of oxygen-free, the above changes were a little observed. (4) On the changes of fatty acid compositions of total lipids, neutral lipid fraction and compound lipid fraction, in the case of control, 18:3, 18:2 acid contents (wt%) in total fatty acids decreased a little, but total saturated acid content increased during storage. In the case of oxygen-free, the changes of fatty acid composition of the above three lipid fractions were slightly observed.

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Antioxidant efficiencies of α-, γ- and δ-tocopherols (Toc) in vegetable oils were investigated by a storage test of potato chips fried with palm oil. (1) In addition to palm oil in freshly use, α-, γ- and δ-Tocs showed no effects on the autoxidation of the potato chips in continuous frying. (2) In addition to palm oil in continuously use, γ- and δ-Tocs showed considerable effects. The effect of δ-Toc was higher than that of γ-Toc. The effects became higher with an increase of the added amounts and lower with an increase of the frying times. (3) α-Toc in the palm oil was markedly consumed in the continuous frying, but the most of γ- and δ-Tocs remained. The similar trend had observed in the oven or AOM tests. (4) The residual amounts of tocotrienol (Toc-3) which contained inherently in the palm oil was the highest in δ-Toc-3, followed by γ-Toc-3 and α-Toc-3. The trend of Toc-3 was similar to that of Toc.

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An experimental breadmaking was performed with usual formula by the addition of several vitamins, essential amino acids or linoleic acid, and the effect of tocopherols (Tocs) on the stability of these nutrients during processing was investigated. (1) Of fat soluble vitamins, β-carotene and vitamin D were lost during breadmaking process, mainly baking by about 20% and 5%, respectively, However, the addition of Tocs reduced their losses to 14% and 0%, respectively. On the other hand, no loss of vitamin A palmitate and linoleic acid, added as safflower oil, was observed even without Tocs. Besides, Tocs remained in bread by about 80% of the amount added to lard. (2) Of B group vitamins, vitamin B1 hydrochloride was lost during the process, mainly baking by about 23%, but the loss was reduced to 5% by the addition of Tocs. On the other hand, vitamin B2 and choline, added as lecithin, were not lost even without Tocs. (3) Essential amino acids were suggested to be generally stable when added in the form of protein, but to be very unstable in whole process of breadmaking from mixing to baking when added in the free forms. Tocs had virtually no effect on stabilizing these amino acids.

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Complex impedance of kiwi fruit during ripening was measured at the frequency range from 200Hz to 500kHz. The diagram of impedance locus showed an arc of a circle and characteristic of Cole-Cole dispersion system, which indicated the validity of the calculation of the impedance parameters on the basis of the equivalent circuit for the biological medium. Some of the parameters thus obtained changed remarkably with ripening. The variation of impedance parameters during ripening was different from that by puncturing fruit with a pin. This shows the mechanism of the softening of fruit by ripening is different from that by puncturing. Several impedance parameters were correlated with firmness of fruit. And among them 'Radius' of the arc resulted the maximum coefficient of correlation of 0.895. These results indicated that impedance measurement was promising for quality evaluation of kiwi fruit. It was speculated that the variation of R₂, r₀ and c₀ in the equivalent circuit was caused by both the lowering of selective permeability of cell membrane and the degradation of cell wall as ripening.

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Six miso samples were prepared from soybeans autoclaved under 1kg/cmcm2 of steam pressure for different lengths of time, and changes in the pattern of SDS polyacrylamide gel electrophoresis (SDS-PAGE) of water-insoluble proteins of the miso samples during 50 days of fermentation were investigated. There were no significant differences in the water-soluble nitrogen contents and in the SDS-PAGE patterns of miso samples prepared from soybeans autoclaved for 1min and over. The similar results as SDS-PAGE were also obtained from the elution patterns of water-insoluble proteins of the miso samples from a Sepharose 6B column in the presence of 6M guanidine hydrochloride. However, the texture of miso sample prepared from soybeans autoclaved for 1min was inferior to the other samples which were prepared from soybeans autoclaved for 10min and over.

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Microbial examination was carried out in order to find the factors affecting to the decolorization of green color of "Hiroshimanazuke" (salted Brassica campestris L. var. pekinensis Rupr.) by the addition of small amount of ethanol. Microorganisms grown in "Hiroshimanazuke" were cultured with the use of squeezed juice of "Hiroshimanazuke" as a basal medium. By the addition of 2% (v/v) level of ethanol, the pH value of the culture medium decreased significantly as compared with the control owing to the production of organic acid, though the growth of microorganisms was inhibited slightly. No microorganisms converting ethanol into organic acid were detected in "Hiroshimanazuke". Ethanol exhibited bacteriostatic effect toward Gram-negative bacteria, but not toword lactic acid bacteria at 2% level. From the results obtained, it was suggested that the decolorization of "Hiroshimanazuke" by the addition of ethanol was due to the increase in organic acid produced by unusually multiplicated lactic acid bacteria.

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Emulsified product with high emulsion activity and stability was manufactured by mixing of frozen sardine fillet with chicken egg and soybean oil in a powerful mixer. The properties of the product differed depending on the ratio of the components and were improved by increasing or decreasing the ratio of egg or oil to the fillet, respectively. The satisfactory standard ratio of the fillet: egg: oil was found to be 2:1:2, and about 50% of the raw sardine fillet was recovered. The product kept the emulsion properties for at least 2 weeks in cold and more longer in frozen state. The general composition of the product emulsified in the standard ratio was approximately 40% moisture, 45% lipid and 10% protein. Amino acid composition satisfied the FAO/WHO requirement, especially with lysine content of twice higher, although sulfur-containing amino adids were somewhat insufficient. In addition, protein efficiency and digestibility were observed to be satisfactory. Fishy odor was depressed and was almost scentless in the fresh product but was developed when the product was kept at room temperature. However, during cold and frozen storages, the repression of the odor was proved to be for one week and much longer. Anti-oxidation of lipid in the product was also observed, similar to that in which some anti-oxidants had been added.

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Fish stick was manufactured for trial from sardine. The mince of round or dressed fish, or coarsely chopped fillet with crushed bone was packed into a case and frozen overnight at -20°C. The block was cut to stick and fried with salad oil. The product was subjected to the organoleptic and plunger tests. There was a little bitterness and fishy odour in the product from the round fish and it was inferior to the products from the dress or the fillet in the hardness. The hardness was not lowered by the addition of salt less than 2% of the flesh or by further addition of the same amount of saccharose. The hardness and the water holding capacity of the products were strengthened by the addition of egg white albumin, wheat protein, soy bean protein, wheat powder and corn starch. The crumb of the stick improved the external appearance and texture of the product. Unpleasant fishy odor was not detected in the vacuum-packaged product even after preservation at -20°C for 2 months.

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The effects of dietary fats (soybean oil, coconut oil, lard and beef tallow) on the changes in composition and structure of triacylglycerol (TG) in muscle lipids of laying hens were studied. The fatty acid composition found in muscle total lipids from each dietary treatment group reflected the composition of fats added to the rations. The TG from thigh and breast muscle were subjected to stereospecific analysis. Generally, C₁₆:0, C₁₆:1, and C₁₈:0 were preferentially esterified at positions sn-1 and sn-3. C₁₈:1 tends to linked to position sn-3 more than other positions, and C₁₈:2 was predominated in position sn-2 of muscle TG. TG species were resolved on the basis of carbon number by high temperature gas-liquid chromatography. The muscle lipids from soybean oil, lard and tallow groups commonly comprised the TG of C₅₀, C₅₂ and C₅₄ as the major TG components, and those from coconut oil group contained many medium chain length TG as C₃₄-C₄₈ components in addition to C₅₀-C₅₄. The TG was separated into simpler molcular species according to the degree of unsaturation by argentation thin-layer chromatography (AgNO₃-TLC). The lipids from soybean oil group contained less S₂M and SM₂ and more of M₂D, SD₂, MD₂, SMT and D₃ species than the other groups, while the lipids from coconut oil group had the highest level of S₃ and S₂M species among the dietary groups. The experimentally determined values of TG species were compared with the values predicted assuming a 1-random, 2-random, 3-random arrangement of fatty acids in intact TG. The agreement was considerably good for muscle TG from lard and tallow groups, but some discrepancies were observed for TG from soybean oil and coconut oil groups. This suggests that in laying hen there is preferential synthesis of some TG species influenced by ingested dietary fatty acids.

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An Indonesian-style dried beef was prepared experimentally and changes in physical and chemical properties of the product during processing were studied. The moisture content of beef decreased to about 20% by weight after drying at 40°, 50°, and 60°C for 12, 9, and 6h, respectively. The water activity after drying at 40°C for 12h was about 0.6 and the hardness of the beef dried at 40°C for 12h was about 2/3 of that dried for 24h. The addition of 200ppm of NaNO₂ to the soaking solution gave a significant positive effect on the redness of the dried beef (p<0.01). The redness was developed well by drying at 40°C for 12h. Residual nitrite content in beef dried at 40°C for 12h decreased to about 30% of that added to the soaking solution. The moisture content, water activity, hardness, and redness of experimental dried beef containing 20% moisture were reversible when samples were kept under 100% humidity for 48h. There were not appreciable differences in main myofibrillar proteins during preparation. These results are suggestive for developing new dried meat products.

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