Analytical conditions of gas chromatographic separation of triglycerides were described. On-column injection system using glass column was superior in higher trighycerides to the conventional sampling method. It was demonstrated that OV-17 has excellent stability up to temperature 400° comparing with other liquid phases SE-30, OV-1 and Versamid 900 by the thermal balance analysis. Reproducibility of quantitative analysis on triglycerides was studied by square method. Relative deviation of each peak area was found less than 5%. Under the beat condition, triglycerides of milk or its products can be determined using ratio index of lower to higher ones.

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A qualitative and quantitative method for dulcin in foods is described. The procedures separating dulcin from a food were based on the effective extraction by partition chromatography in which the mixture of the food and cellulose powder was eluted with acetone containing hydrochloric acid, and the clean-up of dulcin by alumina column chromatography. Dulcin separared from the food was detected by silica gel thin-layer chromatography and determined colorimetrically with p-dimethylaminobenzaldehyde reagent which reacted with dulcin to form a stable color substance with high extinction coefficient. Recovery of dulcin from some foods to which it had been added at 100 ppm levels was of 92-105 per cert.

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The application of DEAE-Sephadex to the problem of separating certifiable acid dyes in foods and the detection of the dyes by thin-layer chromatography are described. The dyes were able to be transfered from a food to DEAE-Sephadex by only shaking mixture of the both, even when they were bound to cellulosic of proteinous substrates. The dyes were eluted from a column of the dyes-bound DEAE-Sephadex with the equivolume mixture of 2N sulfuric acid isopropyl alcohol. The dyes concentration in eluate was satisfactory for its detection by silicagel and thin-layer chromatography. The solvent systems for the chromatography were composed of ethyl acetate-methyl alcohol-aqueous ammonia (4.5 : 1 : 0.7, or 3.3 : 1 : 1). These systems were most recomendable for the separation of the tested dyes in this experiment ; the former was suitable for the separation of the xanthen dyes and the later of the others.

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A rapid method for the detection of six antioxidants (butylated hydroxytoluene, butylated hydroxy-anisole, ethyl protocatechuate, isoamyl gallate, propyl gallate and nordihydroguaiaretic acid) commonly used in foods was described. All the antioxidants were extracted with acetonitrile from hexane layer and the residue after evaporation of the solvent was applied to "Double column chromatography"using both polyamide powder and silicagel columns to eliminate interfering materials and separate the antioxitants to two groups, one containing BHT and BHA, and the other EPC, IAG, PG and NDGA. Each group was then chromatographed on thin-layer plates. The antioxidants added to tallow, lard, olive oil, butter and cheese were easily detected by the method, which will be recommendable to their detection at the presence of two or more kinds of them in a food.

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A part of mercuric compounds was removed with the other precipitates from brines in the purification process of industrial electrolysis. Basal investigation was made on adsorption of mercuric ion on ferric hydroxide gel. The concentration of ferric hydroxide did not affected on pH, at which mercuric ion could be adsorbed on its gel, if the halide concentration were constant. There was resemblance to pH values between decreasing of the relative concentration of mercuric tetrahalide complex and adsorbing of mercuric ion on the ferric hydroxide gel at the constant halide concentrations. These observations suggest that the adsorption of mercuric ion can not be occurred by the formation of its tetrahalide complex. It is also possible that mercuric ion was removed from waste water with co-precipitation or adsorption by the ferric hydroxide gel under the appropriate conditions based on the above experiments.

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The ashing methods for the analysis of fluorine in plant materials were examined. It was found that the method using calcium oxide gives higher and more accurate recovery of fluorine than that using magnesium oxide. The ashing method with calcium oxide gave satisfying recovery from ashed plant leaves on a range of temperature 400°-700°, while the method with magnesium oxide gave maximum recovery of fluorine at about 600°. From these results, it was concluded that the ashing method with calcium oxide is routinely more excellent than that with magnesium oxide.

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Lead and other heavy metals extracted with 4% acetic acid solution at 25° and 80°for 10 minutes from commercial 53 glazed potteries for foodstuff were examined by PbCrO₄-, PbSO₄-, sulfide- and polarographic method, respectively. The amounts of lead and other heavy metals extracted at 80° were larger than those did at 25°. Lead extracted with 4% acetic acid solution at room temperature for 10 minutes from glazed potteries is measured by PbCrO₄- and PbSO₄-method in the "Test of Specifications and Standards of Containers", provided by the Ministry of Health and Welfare. It may be practical that the test solution is prepared by extraction with 4% acetic acid solution at 80° for 10 minutes, from a consideration of the case of plastic containers to be extracted with 4% acetic acid solution at 60° for 30 minutes. The amounts of lead extracted at 80° were within 3 ppm in most samples. Consequently, more sensitive method than PbCrO₄- and PbSO₄- method seems to be required for detection of lead. Lead, copper, zinc, manganese, cadmium, antimony and cobalt were detected in the test solution by polarography. Among them, lead, copper, zinc and manganese were detected in many samples. In the official method, lead is only examined but the method should be attended to other dissolved heavy metals. Furthermore, it is most important that the amounts of extracted heavy metals should be determined per surface area of glazed potteries, because they are not proportional to volumes of the extract but to surface areas.

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Pollutants in some manufactured ice were examined. The results measured about the pollutants such as NH₃-N, NO₂-N, NO₃-N, Cl^- and KMnO₄-consumption were similar to those of other reports. SO₄^2- and Pb, any servey in ice had not yet done, were more concentrated in ice than in original water. It is supposed that SO₄^2- and Pb will come from bubbling air in the process of manufacturing.

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