The gel-filtration-chromatographic and some physicochemical properties of the coloring matter concerning its adsorption and desorption were examined. The gel(Sephadex G-50 Fine)filtrations showed that the coloring matter eluted from the resin consisted of three major components(PA, PB and PC)differing each other in their affinities for the gel. Both PA and PB were sodium salts and their elution curves overlapped over broad molecular weight range. They could not be separated by an ultrafiltration technique and were probably changed their molecular shapes with the solvent used. PC was free acid form of PA or PB, and was adsorbed strongly with the gel. The adsorbed PC could not be desorbed with pure water, but eluted with sodium chloride solution, or with water when sodium chloride or sodium hydroxide was present in the chromatographic sample. Decationized coloring matter which was insoluble in strongly acidic medium and soluble some organic solvents was titratable with alkali to give a pKa value of 4.8, and showed the same behaviors on the gel filtration as PC. From these facts a discussion is given on the effective desorption of the coloring matter from the resin with a mixed solution of sodium chloride and sodium hydroxide.

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Methyl linoleate(ML)(1mmol)and amino acid(1mmol)were adsorbed on filter papers(What-man No. 42, 11-cm in diameter)and the filter papers were incubated at 50°C with 15-20% relative humidity in the dark. After 10 days of incubation, browning was very strong in the mixture of ML with methionine, glycine, proline, lysine or serine. No browning was observed with ML alone and the mixture with N-acetylglycine. Peroxide value(POV)of ML alone or with glycine increased rapidly within 24 hours and decreased quickly thereafter. When glycine was present, the decrease of POV was marked, suggesting that the interaction between glycine and peroxides occurred. POV and the formation of carbonyls were high with cysteine and lysine but low with valine, serine and phenylalanine within 6 hours. The former 2 amino acids exhibited prooxidative activity and the latter 3 amino acids showed antioxidative activity. After 18 hours, browning occurred strongly in the mixture of ML with cysteine or lysine, but almost no browning occurred in ML alone or with glycine, serine, methionine, phenylalanine, proline or N-acetylglycine. Browning of ML(1mmol)with glycine was accelerated with increasing the glycine concentration from 0.01 to 2.0m mol and raising the incubation temperature from 37 to 50°C.

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Peanut oil and glycine or N-acetylglycine were adsorbed on filter papers(Whatman No.42, 11-cm in diameter)and the filter papers were incubated at 50°C with 15-20% relative humidity in the dark. Changes in peroxide value(POV)of peanut oil alone and with glycine or N-acetylglycine were similar and no browning was observed at the initial 25 days of incubation. However, POV increased and browning occurred in peanut oil with glycine thereafter. Almost no browning was observed in peanut oil alone or with N-acetylglycine in 60 days. Autoxidation proceeded more rapidly in Florisil-treated peanut oil than in peanut oil due to the removal of tocopherols. The intensity of browning became much stronger in Florisil-treated peanut oil than in peanut oil by the addition of glycine. When Florisil-treated peanut oil was incubated with amino acids for 5 days, browning was strongest with lysine, followed by proline. POV in all the samples increased rapidly within 2 days and then decreased with increasing incubation time. POV was highest in Florisil-treated peanut oil alone and lowest with proline. In Florisil-treated peanut oil, the formation of carbonyls was slightly higher in peanut oil alone or with N-acetylglycine than with amino acids.

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This study was conducted in order to ascertain a feasibility of near infrared diffuse reflectance method that might be applied to determine the quality grade of dried laver('Nori')in place of seasory evaluation by specialized inspectors. Results obtained were as follows: (1)The higher the quality was, the stronger the absorbance was obtained in all of the wavelength region of 1.1 to 2.5 μm. The variation of absorbance among different grade of the quality showed more distinctly in a longer wavelength region of near infrared. (2)There was a tendency that the absorbance around 2.0 to 2.2μm of wavelength region showed less intensity for a higher grade of the quality. (3)A single linear regression ana1ysis was made between the grade of the quality and absorbance at about 35 bands obtained in the spectrum using an original log(1/R), the first derivative dlog(1/R)or the second derivative d²log(1/R)spectra. According to the correlation coefficients at the wavelengths of 2.056, 2.110 and 2.168μm, especial1y, it was suggested that the higher the grade of the quality was, the more protein content was and by contraries the less carbohydrate content was. (4)On the other hand, the reu1ts of multiple linear regression analysis showed that near infrared diffuse reflectance method had a high capability to determine the grade of the quality of dried laver relating to a chemical composition provided the second derivative spectra might be used.

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The cooked odor concentrates of commercial salted guts(SHIOKARA)of three different species of Mysid shrimps were obtained by simultaneous distillation and extraction with NICKERSON'S apparatus. Thirty six Compounds, including nine pyrazines, eleven sulfur compounds, four alcohols, five ketones and seven others were identified by GC and GC-MS. Main components in the odor concentrates of commercial SHIOKARA(I, II and III)were pyrazines, ethanol, isovaleraldehyde and sulfur containing compounds. Among three products, qualitative and quantitative differences were observed on gas chromatograms, which were considered to contribute to the quality of the commercial products.

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Distribution and status of zinc in the grains of soybean were investigated by using an atomic absorption spectrophotometer. An ultrafiltration, gel filtration and ion-exchange chromatography were applied to the fractionation of zinc which was associated with predominant components of the grains. Japanese soybean harvested in 1980 was used as the experimental material. Zinc content of the soybean seeds was 42.0μg per g of dry matter. The zinc distributed in the seed coat, germ and cotyledon in the ratio of 6:2:92. Eighty percent of zinc in the seed coat was associated with the substance which could not permeate into the membrane whose molecular weigh exclusion limit was 3×10⁵. pH of soaking solution affected the zinc elution from the whole grains remarkably. Eluted amount of zinc was the lowest at pH 4-5 which is equivalent to the isoelectric point of soybean proteins, and the elution curve resembled to that of nitrogen. Based on the facts, the existence of zinc bound to soybean proteins was assumed. The assumption was supported by profiles of gel filtration. The profiles suggested also the existence of zinc associated with some low molecular substances whose molecular weight was under 1×10⁴. These substances were considered to be two or three kinds of each sugar, nitrogen and phosphorus-compounds, but they are not identified.

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A spectrophotometric method based on the difference spectra before and after oxidation of L-ascorbic acid(AsA)by ascorbate oxidase(EC 1. 10. 3. 3)was developed as a simple, rapid and sensitive method for AsA estimation. The present paper describes the determination of dehydroascorbic acid(DAsA)and total AsA(AsA+DAsA)by this difference spectral(DS) method. First the reduction condition of DAsA with dithiothreitol(DTT)was investigated. DAsA was completely reduced to AsA by the treatment with 100mg% DTT-ethanol solution for 15 min at 30°C. After the reduction, total AsA was determined by the DS method, DAsA being calculated from the difference between total AsA and AsA. The values of total AsA and AsA estimated by the DS method and the 2, 4-dinitrophenylhydrazine(DNP)method agreed very well in satsuma mandarin and tomato juice samples used. But, the DAsA values obtained by the DS method were lower than those by the DNP method, in which 2, 3-diketogulonic acid value was uncorrected, in satsuma mandarin juice. The recovery of DAsA added to the juice sample ranged from 101 to 103%. Thus, it is possible to determine not only AsA but also total AsA and DAsA by the DS method.

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The effect of the soybean protein ratio on the physical properties of sausage-like meat products containing two kinds of soybean proteins has been investigated. The jelly-strength and the water-holding capacity of the meat product containing acid precipitated soybean protein decreased according to the increase of the soybean protein ratio. While the jelly-strength and the water-holding capacity of the meat product containing commercial soybean protein isolate increased in proportion to the ratio of soybean protein. The YOUNG'S modulus of both the meat products containing acid precipitated soybean protein or commercial soybean protein isolate decreased with the increase of soybean protein ratio.

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