Outline of awards prominent for outstanding studies, by the Japan Oil Chemists' Society in 1993 is presented. The studies are enumerated as follows :
1) Suface chemical studies on interactions between phospholipid vesicles or oil/water and ionic compounds.
2) The synthesis of polymer latices with different structures.
3) Fine particle suspension stability including high molecular compounds.
4) The long range attraction forces between the particles.
5) The electrokinetic measurements.

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A mixture of α-tocopherol and rosemary extract, as additives each at 0.035% (total 0.07%), expressed very strong antioxidant activity in sardine oil stored at 30°C, 50°C and dried sardine meat at 5°C. In sardine oil, their combination not only inhibited the formation of hydroperoxides much more effectively than when present separately but the activity of tocopherol was retained for a longer period. In dried sardine meat, combined application caused the lowest PV, and (EPA+DHA) /16 : 0 was higher. There was also lesser decomposition of triacylglycerol due to oxidation. Synergistic antioxidant effect was observed in sardine oil at 30°C and 50°C, and in dried sardine meat at 5°C. The antioxidant activity of rosemary extract was lost at of 90°C, as was also the synergistic effect.

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A combined system of liquid-liquid extraction and membrane separation was developed to concentrate and separate polyunsaturated fatty acids (PUFAs) as acylglycerols from the hydrolysate of fish oil, after being selectively hydrolysed with lipase. With consideration to potential industrial applications to membrane separations, conventional cross-flow filtrations and rotating disk membrane systems were examined.
In the cross-flow filtration system, permeate flux decreased rapidly during one-run batch treatment. Showing comparatively poor performance. The use of a gear pump in the system damaged oil quality. In the rotating disk membrane system, permeate flux did not decrease and separation performance was good. The O/W emulsion in the cross-flow filtration system differed from that in the rotating disk membrane system. Average oil droplet size in the rotating disk menbrane system was larger, than that in the cross-flow filtration system. This possibly being a factor affecting membrane separation.
The rotating disk membrane system was concluded applicable on a large scale process to the separation of physiological substances such as PUFAs which are easily damaged.

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The removal of myristic acid by aqueous alkyl poly (oxyethylene) ether type nonionic surfactant (C_mEO_n) solution was conducted by solubilization in surfactant micelles. Actual removal after 24 h by hepta (oxyethylene) ether (C₁₂EO₇) solution at various concentration and 30°C was in fair agreement with that calculated, based on the extent to which myristic acid A (sat), linearly related to the concentration of surfactant, could be solubilized. It is thus evident that removed myristic acid soil is solubilized in micelles. Linearity of the reciprocal plot of the V_init, determined from the slope of the tangent line drawn through the origin (washing time=0), against 1/A (sat) shows that myristic acid soil is removed by the multi-step solubilization mechanism proposed by Shaeiwitz et al.
The effects of temperature on solubilization and removal of myristic acid were studied. At equilibrium, a clear isotropic solution was obtained at 2040°C, while opaque white dispersions were observed at above 45°C. Based on FT-IR measurement, the latter appeared to result from dispersions of ternary liquid crystalline (LC) (myristic acid-C₁₂EO₇-water). The removal of myristic acid improved with increase in washing temperature, and after 24 h at 2040°C was quite similar to that calculated from the limit of solubilization. However, above 45°C, actual removal was less than that determined from the extent of LC dispersion.
The effects of change in the structures of nonionic surfactants on the temperature dependency of solubilization of myristic acid were examined by varying the numbers of alkyl (m) and oxyethylene groups (n).

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The microstructure of the one-phase region in quarternary system of sodium oleate/ water / monobutyl poly (oxyalkylene) ether/hydrocarbon was examined by electrical conductivity, viscocity and pulsed field gradient spin-echo (PGSE) NMR measurements.
Structural transition from the water-continuous to bicontinuous and oil-continuous microemulsion was detected based on water content in this system.
Soil removal was studied to determine the effects of microemulsion structures, using glycerol trioleate, lanolin and abietic acid as model soils. Rolling-up was occurred only in a bicontinuous microemulsion, indicating low interfacial tension of the bicontinuous structure to possibly facilitate the penetration of surfactant and monobutyl poly (oxyalkylene) ether molecules into the soil, followed by rolling-up.

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The oxidation products of linoleic acid were isolated and their removal from fabrics was investigated. Hydroxyoctadecadienoate was isolated by HPLC using acetonitrile/water (8/2 by volume) as a mobile phase at a retention time of 4.6 min. Two dimeric compounds were separated similarly using acetonitrile/tetrahydrofuran/water (6/3/1 by volume) at 6.0 and 9.6 min. All three compounds were quantitated by HPLC, as indicated by the good linear relationship between peak area and content of each.
Removal efficiency from fabrics by SDS decreased in the order of hydroxyoctadecadienoate, linoleate, and two the dimeric compounds. The same order was observed when linoleate and its oxidation products were mixed.

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Examination was made of the decomposition of ledene oxide (1), β-cedrene oxide (2) and humulene oxide (3) with formic acid in the presence of synthetic zeolites. The decomposition of (1) with formic acid in the presence of 1010 AH, 2020 AH, HSZ-330 HUA or HSZ-330 HSA zeolites afforded predominantly 5-isopropeny1-2, 8-dimethylbicyclo [5.3.0] dec-2-en-1-ol (4) in high conversion (83 % at optimum). The decomposition of (2) with formic acid in the presence of 2020 AH zeolite gave 2, 6, 6-trimethyltricyclo [5.3.1.0^{1, 5}] undecan-8-one (9) as a main product, or 74 % of all decomposition products. With 13 X zeolite, 2, 6, 6-trimethyltricyclo [5.3.1.0^{1, 5}] undeca-8-ene-8-carbaldehyde (10) was obtained as the main product with high conversion (71 % at maximum). The decomposition of (3) with formic acid in the presence of HSZ-600 HOA zeolite gave 4, 8, 11, 11-tetramethyltricyclo [6.3.0.0^{2, 4}] undec-9-en-5-ol (14), as the main product with high conversion (87 % at maximum).

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Selective preparation of epoxide with high conversion from 8 (9) - [2- (perfluorooctyl) ethoxy] tricyclo [5.2.1.0 ^{2, 6}] dec-3-ene (1) obtained as the adduct of 2- (perfluorooctyl) ethanol and dicyclopentadiene was described.
Two epoxidation methods were used for this purpose : m-chloroperbenzoic acid (m-CPBA) and t-butyl hydroperoxide (t-BuOOH) in the presence of a metal acetylacetonates as catalysts. With m-CPBA at room temperature in chloroform, conversion and selectivity reached almost 100 %.
With t-BuOOH, MoO2 (acac) 2 was more useful than VO (acac) 2. Optimal conditions were [MoO₂ (acac) ₂] ₀=0.6 × 10^-4 M, [t-BuOOH] ₀=0.02 M, [1] ₀=0.10 M at 60°C in toluene. Selectivity was nearly 100 % and conversion 94 %.
m-CPBA may thus be concluded an effective reagent for the epoxidation of (1).

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Additive effects of extracts from sesame seeds for preventing the oxidation of fish oil (sardine oil) were examined by the Rancimat method at 80 °C under 20 L/h air flow or by an oven test at 5 and 20 °C. Extracts were obtained from raw and roasted sesame seeds using water, methanol and ethyl ether as extracting solvents. In the Rancimat test, the ethyl ether extract clearly inhibited fish oil oxidation while water and methanol extracts exerted no such effect. The ethyl ether extract suppressed peroxide formation in the oven test, but expressed greater antioxidant effect at 5 °C than 20 °C.

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Residual sterylglycosides (SG) and octacosanedioic acid (DA 28) in commercial sesame oil were investigated for 17 brands of 12 manufacturers. A sensitive and precise method was developed to determine DA 28 content in oil. DA 28 was derived from 9-anthryldiazomethane in the presence of triacylglycerol and determined by HPLC equipped with a fluorescence detecter. This method was rapid and applicable to routine analysis.
SG and DA 28 content differed considerably according to brand, from 1 to 300 ppm and 0 to 1500 ppm, respectively. The steps in oil processing would thus appear to markedly affect SG and DA 28 residue content

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