Changes in microflora of ozone-treated cereals, grains, peas, beans and spices, packaged in a polyethylene pouch and stored at 10, 30°C for 30days were investigated. The conditions to evaluate the ozone treatment effect on various samples were: ozone concentration, 0.5-50 ppm; temperature, 10°C; time, 1h and flow rate of ozone-oxygen stream, 100l/min. Results were as follows: 1) Bacillus and Micrococcus have been found to be the main microflora of cereals, grains, peas, beans and spices. The number of the main microorganisms of these samples could be decreased by a factor of 10-10³ by the ozone treatment below 50ppm and further decreased during storage. 2) At 10 and 30°C storage, a decrease of total microbial count was mainly ascribed to ozone remained in a polyethylene pouch. Cereals and grains kept ozone for relatively long period. 3) The preservation lives of cereals, peas, beans, grains and spices were extended by ozone treatments above 5, 5, 5, 0.5, and 50ppm, respectively.

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We have previously¹⁾²⁾studied the cooking-rate equations expressing the hot water dipped cooking of sliced and spherical potatoes. In this paper, we studied a microwave cookingrate equation of cylindrical potato. The values of Arrhenius parameters in the equation were calculated by using a non-linear least square method. The cooking-rate equation obtained was as follows:
Where x(-) is the cooking ratio, θ(s) the cooking time, T(K) the cooking temperature and R_g gas constant 8.314 J·mol^-1·K^-1. The value of activation energy obtained was lower than 1.23-1.24×10⁵ J·mol^-1 obtained for the hot water dipped cooking.

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Wounding is one of undesirable phenomena during post-harvest handling and storage of vegetables, because it causes their deterioration. The changes in the hydroxyproline content and its distribution in cell walls of vegetables were investigated to clarify the effect of wounding on changes of cell wall components. The hydroxyproline content in cell walls of wounded vegetable increased during incubation at 20°C. The increase ratio of hydroxyproline by wounding was found in the order; potato>cucumber>Japanese radish>sweet potato>tomato>turnip>lotus root>pumpkin>sweet pepper>carrot. The hydroxyproline of sweet pepper was distributed in pectin, hemicellulose I, hemicellulose II and cellulose fractions in the cell wall. The hydroxyproline content in hemicellulose I fraction was more than that in the other fractions. Both hydroxyproline and protein contents were increased in every fractions of the cell wall by wounding, suggesting that the hydroxyproline-containing proteins are increased in all fractions of the cell wall by wounding. Although the amino acid composition of the hemicellulose I fraction was similar to that of the hemicellulose II fraction, the percentage of hydroxyproline was higher in hemicellulose II fraction than in hemicellulose I fraction. Moreover, the percentage of hydroxyproline in hemicellulose II fraction was slightly increased by wounding. The hydroxyproline/protein ratios in hemicellulose II and cellulose fractions tightly bound to the cell wall were increased by wounding, but those in pectin and hemicellulose I fractions weakly bound to the cell wall were not increased. Therefore, it is suggested that wounding induced more strongly the linkage of hydroxyproline-containing protein to the cell wall with passage of time.

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The changes of protein, amino nitrogen and free amino acids during rehydration and cooking process of dried Shiitake mushroom [Lentinus edodes (Berk) Sing.], were investigated. As the soaking proceed, protein content was decreased and amino nitrogen was increased. All free protein-amino acids were increased in soaking and the rate of increasing was raised by rising soak temperature. On the contrary, free non-protein amino acids were almost unchanged. These facts suggested proteinase action in the soaking process. In cooking process after soaking both free protein and non-protein amino acid were almost unchanged. Amount of lentinic acid, the precursor of Shiitake aloma lentionine, were decreased both in soaking and cooking process. From these results, the taste and odor of cooked dried Shiitake mushrooms were discussed.

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The behavior of water in frozen starch-water gel during rewarming has been studied by differential scanning calorimetry. Water-starch mixtures were prepared using potato and corn starch with water content from 45% to 83% and were heated at 80°C or 120°C. DSC curves were obtained at the heating rate of 2°C/min. after cooling to-50°C. Two melting peaks of ice were observed in the gelatinized starch at the water content below 60%. This indicated that there were two kinds of ice in starch gel on freezing state. One which had a melting temperature about O°C was ice of free water and another with lower melting temperature was that of restricted water. The melting peak of restricted water changed its shape and peak temperature during storage at 5°C. Those phenomena depended on the kind of starch, heating temperature for gelatinization and water content. It was considered that those changes were caused by the change of the networks of starch gel. The changing aspects of this peak in potatostarch gel preparing at 80°C were identical with those of corn starch gel prepared at 120°C.

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The chewing gum base is mainly composed of chicle, jelutong, sorva, polyisobutyl ene and polyvinylacetate. By using these materials as gum base, we prepared various samples containing different amounts of l-menthol, 1, 3 and 5%, and experimented on the c hange of remaining l-menthol after masticating these samples. The order of the ratio of r emaining l-menthol was jelutong>chicle>sorva>polyisobutylene>polyvinylacetate, and th e ratio of remaining l-menthol was approximately correlated to the chewing time by an eq uation "MR=100-at^0.68" " (MR: the ratio of remaining l-menthol, t:the chewing time). A nd we checked the mechanical properties of these samples before masticating. The chang ed ratio in dynamic viscoelasticity between the samples with and without l-menthol closely r elated to the ratio of remaining l-menthol after masticating these samples. These results will enable us to predict the release of l-menthol during mastication by measuring the mecha nical properties of a sample.

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Following results were obtained from chemical analyses and sensory tests of Sunki pickles prepared from Gishigishi (Rumex japonicus) and "Bulgarian Yoghurt" (Meiji Dairy Co.) as the source of Lactobacillus bulgaricus and Streptococcus thermophilus:
(1) Favourable pickling period for 500g of Gishigishi-leaves with 50g of the yoghurt at 5°C was 4 weeks. (2) A decrease of alanine, and an increase of aspartic acid which is a tasty amino acid, were observed during pickling process, and oxaloacetic acid was detected in the pickling juice. (3) Above mentioned results suggest formation of aspartic acid by transamination of alanine to oxaloacetic acid, which might be derived from malic and succinic acids in the leaves.

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Determination of mixing ratio of Wasabi and horseradish in pastes were investigatedusing gas chromatograph equipped with FPD. (1) Five kinds of Wasabi flour and 10 kindsof horseradish flour were used in the preliminary test. The peak area (PA) of 4pentenylisothiocyanate (Itc), 5-hexenyl Itc, β-Phenethyl Itc and unknown compound X on thechromatogram of the hydrolysates of the mixture of the samples mixed with various ratioswere calculated. Relation curves between square root of (PA of individual compound/PA ofinternal standard, phenyl Itc)×100 and mixing ratios of the compounds gave straightlines. (2) The mixing ratios of Wasabi and horseradish in the pastes collected from themarket were estimated from the square root values obtained with above mentioned 3compounds except β-phenethyl Itc by the relation curves.

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The effects of membrane permeability on the flux and quality of raw and limed cane juice on ultrafiltration were studied by 2-3 h long-term testing(of several types with molecular weight cut-off levels from 50 000 to 100 000). The flux through XM-50, XM-100 and A-50 Tmembranes for raw juice remained at the value of about 0.100 ml·cm_-2·nub_>-1 until permeation volume of 250 ml, but it then decreased gradually. The flux of A-50T membrane was the greatest at the initial stage(with O.140 ml·cmcm_-2·min_-1), and then decreased gradually d gradually when juice limed to pH 8.1 at 10°C was used. The flux of juice limed to pH 7.0 at 85°C showed remarkably high value (at the initial stage), however it decreased rapidly with increasing permeate volume. The flux of A-50T membrane showed comparatively lower value than that of XM-membranes. The sucrose rejection of the permeate with the XM-50, XM-100 and A-50T membranes was 2, 2-5 and 5-7% for juice limed to pH 7.0 at 85°Crespectively.

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