Polymerase Chain Reaction (PCR) was applied to identification of meat and meat products of different species. To distinguish meat from fowl and fish, primers RR-1 (5' -AAACTGCGAATGGCTCATTAAATCAGTT-3' ) and RR-6 (5' -ATCGAAAGTTGATAGGGCAGA-3' ) were designed for the regions of 18 S ribosomal RNA gene. The template were 200 ng of genomic DNAs purified from meats of nine mammals, eight birds and two fishes in species. Amplification was carried out 35 cycles of denaturation at 95°C for 0.5 min, annealing at 60°C for 0.5 min, and extension at 76°C for 0.5 min. Amplified products were analyzed on 5% agarose gel electrophoresis. Mammalian DNAs gave 293 by PCR products except kangaroo DNAs from which 317bp fragment was obtained. The PCR products of bird DNA and two fish DNAs gave specific fragments of 254 by and 267 bp, respectively. The sequences of the PCR products from kangaroo, cattle, crocodile, turkey, frog and alaska pollack were determined using the Dye Deoxy Terminator Cycle Sequencing method, for which all PCR products above described are corresponding parts of all 18 S ribosomal RNA gene. The variation in length of PCR products between mammals, birds and fish is due to the difference in 10 loop regions of 18 S ribosomal RNA gene. Based on this difference of 18 S ribosomal RNA gene, several meat products were analyzed by agarose gel electrophoresis. Mixture of pig, chicken and fish in meat products could be identified from each specific fragments by the PCR assay. Each specific fragment from these mixed meat products could be identified by only one series of PCR reaction.

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Low temperature-high speed dehydration of a high moisture content material by vertical air blowing from a narrow slit to the surface of the material moving horizontally was studied. As a part of this study, prior to drying experiment blowing out of aqueous solutions on a surface of flat plate by air blow was measured under different conditions of air velocity (ν_a), moving velocity of the plate (ν_s), viscosity of solution (μ), and initial thickness of solution (δ₀). These measurements were made using several kinds of viscous oils instead of aqueous solutions to obtain the data without evaporation, and the results were compared with a model equation derived in this study. The experimental results were well correlated with a parameter ν²_a/μν_s, and agreed well with the model equation. On the other hand, the effect of initial load was negligible in the equation with the value of k evaluated from the experimental result. From these results, a simple approximate equation was obtained independently of initial load. This equation also agreed well with the experimental results.

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The aroma concentrate from brewed black tea (Darjeeling) were obtained by a Porapak Q column adsorption method followed by elution with diethyl ether: isopentane (4:1) solution. Twenty-three peaks with the higher flavor-dilution (FD)-factor, which significantly contribute to black tea aroma, were found by aroma extract dilution analysis (AEDA) of the aroma concentrate. Twenty-eight components were identified by GC-MS and MDGC. Linalool and vanillin were found to be the most potent aroma components. Phenylacetaldehyde, methyl salicylate, hexanoic acid, geraniol, guaiacol, (Z)-3-hexenoic acid and heptanoic acid were also important aroma components. Of all the aroma components, 5-ethyl-2, 3-dimethylpyrazine, 2-acetyl-3-methylpyrazine, 2-hydroxy-3-methyl-2-cyclopenten-l-one and 4-vinylguaiacol have been found in black tea for the first time. Besides the FD-factor of Darjeeling black tea, those of Assam and Uva black teas were also measured. Twenty-three peaks identified in Darjeeling black tea were similarly confirmed in Assam and Uva black teas, and accordingly the difference of overall aroma of three kinds of black teas were found to be caused by different concentration of the potent aroma components.

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On mineral availability, it's important to clarify mineral distribution in food material. Using X-ray analytical microscope (XAM), we have investigated each distribution of K and Ca in 5 cultivars of sweet potato. K was highly distributed in the epidermis in contrast to high Ca content in cortex. The results from XAM analysis were compared with those of conventional quantity analysis such as ICP-AES. They were in good accordance with each other. From the results of ICP-AES analysis, we found that the epidermis contained much amount of Mg as well as K.

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Lycopene is one of the naturally occurring carotenoids, which owes its red color attributable to the presence of an extensively conjugated polyene structure. Such a structure renders lycopene susceptible to oxidation. Extraction of lycopene in tomato skin was studied with supercritical carbon dioxide (SD-CO2). The recovery ratio of lycopene differed according to drying methods. After being dried each tomato skin by hot-air-drying, freeze-drying or dehydration with ethanol, lycopene was extracted using SC-CO₂ (100-270 kg/cm², 35-60°C). In the case of dehydration with ethanol, the recovery ratio of lycopene was the highest (about 90%). The recovery ratio of lycopene increased with an increase in pressure and was the highest at 40°C.

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The decomposition of allyl isothiocyanate (AITC) in an aqueous solution (pH5.0, I_c= 0.75M) was promoted in the presence of some amino acid under mild condition (40°C), depending on a kind and concentration of amino acid used. Amino acids containing nucleophilic group indicated the larger decomposition rate of AITC. It suggested that the decomposition of AITC was promoted by nucleophilic attack of amino acid. Especially, 1mM cysteine promoted the decomposition of AITC markedly. It was suggested that SH group in cysteine contributed to interaction between cysteine and AITC, and the rate constant for the interaction was larger than any other amino acid.

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The densities and the vapor pressures of two fruit juices (orange juice and apple juice) of concentrations ranging 10%-60% (w/w) were measured at temperatures between 10°C-60°C by the pycnometer method and a static method, respectively. On the basis of the measured results, the effects of concentration and temperature on the specific volume, which was the reciprocal of density, and on the vapor pressure were investigated. The specific volume and the vapor pressure were written as a function of both temperature and concentration, respectively. These equations were used in conjunction with the Clapeyron equation to calculate the enthalpies of vaporization for two fruit juices. Finally, the obtained results were compared with the results calculated from an empirical equation, which is convenient to the practical use.

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