High moistured cereal flour gels harden easily on their short time storage. To prevent hardening of the gels, α-amylase, β-amylase, glucoamylase or papain was added to rice and wheat flour gels at several concentrations and stored in a refrigerator for 1 to 3 days. The changes in hardness of their gel strength were measured by use of Autograph (Instron type testing machine). The gel strength of rice and wheat flour gels was markedly decreased with addition of 0.0005 to 0.005% α-amylase and hardening were delayed. But the use of α-amylase was unsuitable for gel formation in the textural aspect. The addition of β-amylase at the concentrations of 0.05 to 0.1% delayed effectively the increase of gel strength in rice flour gel, but not so effective to wheat flour gel. Glucoamylase and papain were little effective to depress the increase of gel strength on storage at a lower temperature. Hardening of the Uirou (a confectionery of rice flour gel) prepared experimentally with addition of 0.05 to 0.1% β-amylase was considerably delayed and its good texture was retained during storage.

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A method, for the quantitative determination of α-chaconine and α-solanine in potato glycoalkaloids (PGA) of May Queen' has been developed using a high-performance liquid chromatography (HPLC). (1) After extraction with chloroform:methanol (2:1, v/v), PGA were separated on a column of Nucleosil NH2 (10μm), and eluted with tetrahydrofuran:0.25M monopotassium phosphate buffer: acetonitrile (50:25:25, v/v) at the flow rate of 1ml/min. The column effluent was monitered at 208nm. A total analysis of α-chaconine and α-solanine was completed with 15min, and their separation and quantification were satisfactory. (2) It was found that the recovery was 96.8% for α-chaconine and 89.8% for α-solanine and also that two substances were fairly stable within general homecooking temperature (<150°C). (3) By the determination of PGA in the periderm and the cortex of potatoes by HPLC, it was found that almost all of PGA were existed in the periderm; moreover the contents of them were higher in both apical and basal sections than in central section. In the cortex, α-chaconine content showed no changes in three different sections while α-solanine was detected as traces.

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The trend of fresh vegetables consumption in Japan was analyzed here using the Annual Reports "the family income and expenditure survey" (1963-1982). Analytical method employed was the maximum marginal likelihood method for smoothing serial data, which was characterized to provide both an estimator of an alternative smoothing regression curve and a test procedure. This method was proved to be excellent for analyzing the trend for serial data and results obtained are summarized as follows: (1) Total consumption amounts of fresh vegetables in house-hold varied from up to down in these 20 years. Maximum consumption amounts of fresh vegetables was calculated to be attained in 1973. (2) Total consumption amounts of root vegetables have linearly increased. On the other hand, those of fruit vegetables significantly varied from increase to decrease. (3) This trend of fruit vegetables consumption was not provided with a certain items but attributed to similar behaviors of 5 items among 6 items of fruit vegetables. (4)It is interesting that consumption amonuts of carrots, among root vegetables, showed steady increase. (5) Chinese cabbage, consumption amounts of which decreased most rapidly, showed accelerating the rate of decrease.

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In rehydration and cooking process of dried Shiitake mushroom (Lentinus edodes (Berk) Sing.), effects of soak temperature and time on water absorption, browning and change in RNA and 5'-GMP contents were investigated. Up to 40°C, the rise of soak temperature produced a decreasing the soak time required for rehydration. Soaking at high temperature resulted in a decreasing the amount of water absorbed and a hastening of browning. The content of RNA was decreased as soak time increased, and the rate of its decrease increased by rising soak temperature. The level of 5'-GMP was low during soaking and was slightly decreased by soaking below 40°C. Boiling after soaking resulted in a decrease in RNA content and a significant increase in 5'-GMP content. But the increasing of 5'-GMP was slight or none, when the mushroom was soaked for long time or at high temperature.

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The contents of potassium, sodium, calcium, magnesium, phosphorus, iron, copper, zinc, manganese, cadmium, lead, arsenic and mercury in 24 species (27 samples) of wild edible mushrooms and 5 species (6 samples) of cultivated mushrooms, collected and purchased in Tokyo, Tohoku and Chubu districts from 1979 to 1980 were determined. The results were as follows; K: 1.1-5.3%, Na: 11-267mg/100g, Ca: 5-342mg/100g, Mg: 59-299mg/100g, P: 59-1938mg/100g, Fe: 4.9-419.4mg/100g, Cu: 0.2-23.2mg/100g, Zn: 0.4-16.3mg/100g, Mn: 0.8-10.2mg/100g, Cd:0.0-38.8ppm, Pb: 0.0-17.1ppm, As: 0.0-18.0ppm, and Hg: 0.0-6.3ppm in dry basis, respectively. There were remarkable differences in the mineral contents among the different species of edible mushrooms. Some characteristics were found in the mineral contents of the samples belong to the same species.

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Candida lipolytica yeasts were cultivated on a medium containing pig bone fat or glucose as a sole carbon source. The cell yield was significantly higher in culture grown on bone fat than on glucose medium, and the lipid contents of cells were slightly higher in the yeast grown on bone fat than on glucose. Although, the contents of neutral lipid in total lipid were nearly the same as yeasts on the both media, the bone fat grown cells contained more phospholipids and less glycolipids than the glucose grown cells. The extracted lipids from cultured fluid grown on bone fat contained considerable amount of free fatty acids, and small amount of diacylglycerols and monoacylglycerols. This results suggested that the yeasts grown on fat with a hydrolyzing process of triacylglycerols, and that the hydrolyzed fatty acids from bone fat were incorporated into cell body for use as the composing stuffs of cellular lipids. The neutral lipids of yeast cells composed of triacylglycerols, free fatty acids and diacylglycerols, and then, contained monoacylglycerols and sterol esters as minor ingredients. The major components of polar lipids from yeast cells were considered as phosphatidylethanolamine, phosphatidylcholine, phosphatidylserine, ceramide monohexoside and ceramide dihexoside. The fatty acid compositions of these lipids components from yeast cells were comparatively investigated on the cellular lipids of C. lipolytica grown on bone fat and on glucose media.

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Dietary fiber (DF) contents of soybean and soybean foods, kinako, natto, akadashi-miso, hacchomiso and okara, were determined by the detergent fiber method of Van Soest. Pectin, main undigestible polysaccharide of soluble DF, and crude fiber were also determined. Okara had the largest total DF value. Fermented foods, miso and natto, were low in hemicellulose and pectin contents. Kinako had remarkable high value in neutral detergent fiber (NDF). The NDF fraction from soybean contained nitrogen compounds which increased with heating. By means of differential thermal analysis using DSC, it was found that insoluble compounds was derived from protein, pectic substance and others during the heating procedure and were taken into NDF fraction at the time of DF determination. Since insolubilized protein in the NDF fraction was digested by the treatment of proteases such as pepsin and trypsin, it was proposed to treat NDF with proteases for the determination of DF in the heated soybean products such as kinako.

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When the molasses was decolorized by the action of wood-white-rotting basidiomycetes in growing culture, often a coloration of molasses was observed in early stage. Generally, basidiomycete has polyphenol oxidase (PPO) activity and molasses contains various kinds of phenolics. Hence, it was considered that the coloration was caused by oxidation of the phenolics by the action of PPO of basidiomycetes. These phenolics were removed from the sample molasses using polyvinylpolypyrrolidone (PVPP) which is a specific adsorbent of phenolics. PVPP-treated molasses could be decolorized without being accompanied with coloring phenomenon. Coriolus versicolor IFO 4937 (Dec%, 84.4%), Coriolus hirsutus IFO 4917 (82.8%) and Lenzites betulina IFO 6266 (80.6%) had higher decolorizing activity, but they assimilated sucrose. As one index of decolorizing activity with lesser consumption of sucrose, we defined a S/A value. Based on this value, Pleurotus ostreatus IFO 6519 (S/A value, 18.56) and Oxyporus populinus TMI 50016 (17.08) belonging to Type 2 were selected as basidiomycetes which was suitable for decolorization of PVPP-treated molasses in growing culture.

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The spinnability was studied with a series of starch pastes prepared from starch granules of potato (2.0-5.0% (w/v)), waxy corn, corn and wheat (5.0% (w/v)). Potato starch pastes were heated at 80°C and 98°C for 2, 30 and 90min, and the other starch pastes were heated at 98°C for 2min. The spinnability was measured by using a Rheolometer, while the measurements were made to obtain flow properties and dynamic viscoelasticity of the pastes so as to compare the spinnability of the samples. The spinnability of potato starch pastes was greater than that of waxy corn starch pastes under the same concentration and heating conditions. However, corn starch and wheat starch pastes showed a very little spinnability. At the same heating conditions, the spinnability of potato starch pastes in different granule concentrations increased while their consistency indices K, the dynamic moduli G' and the dynamic viscosities η' increased. The spinnability also closely related to the relaxation time τ for the samples showing the similar values of the dynamic viscosity η'. Consequently, a linear relationship could be obtained between the spinnability and the product of n' and τ for the starch pastes.

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Effect of Citric acid and sugar concentrations on the consumer preference for beverages containing 10%, 20% and 30% Kaki puree, and how the concentration of Kaki puree affects the taste of beverages were examined by sensory tests. (1) Preferable acidity and sugar content of the beverage were 0.35% and Brix °13.0, respectively. (2) Beverage containing 20% puree had a preferable tendency than those containing 10% and 30% puree, but there was no significant difference. (3) Sour intensity increased proportionally to acid concentration, but it was decreased by the concentration of sugar added.

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The rate of production of volatile acids present in the intermediate products at 3, 4, 10 and 15 months of fermentation of commercial Patis obtained in the Philippines and fish sauce of small scale preparation made in the laboratry was investigated. Also, an attempt to clarify the origin of these acids was conducted. Results of these experiments showed that concentrations of low molcular volatile acids were found to be higher in gut than in the whole and in flesh of fish in the both 24hours and 1 week incubations. It was also found that acids increased quantitatively and qualitatively with the progress of fermentation. It seems that almost all the acids identified in the sauce were formed within 3 months of fermentation. In this study, when fish was incubated without the addition of salt, most of the acids found reached very high levels compared with that in the fish incubated with the addition of salt. This might suggest involvement of bacterial action in the production of volatile acids.

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