Utilization of press juice of citrus waste peels for single-cell protein(SCP)production was studied. At first, the composition of medium for screening of yeast strains was determined. It was found that nitrogen compound and phosphates were necessary to supplement when the press juice was utilized as the medium. Minerals and vitamins had no effects. The growth of one hundred and twenty-five strains were tested on screening media. The protein content of strains which showed high growth yield were also determined. As the results, three strains, Candida sp. (MMC-5A), Candida sp. (OIPC-1A)and Saccharomyces cerevisiae No.79, were selected for further investigations. The best yield and the highest crude protein content were obtained on the medium whose composition was as follows; dry matter(originating from citrus peel juice): urea: KH₂PO₄=50:5:1. The growth of cells was 35g/l, which correspponded to the yield of 50% to total sugars(or the yield of 35% to dry matter), and the crude protein content of cells was around 45%.

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To preserve high and intermediate moisture confectionaries, the influence of their initial viable count, moistnre content and water activity on shelf life were studied. The application of oxygen absorber for preserving confectionaries were also studied. (1)It was confirmed that three types of commercially available oxygen absprbers had prescribed oxygen absorbing power. (2)A good correlation was found between water activity and moisture content of confectionaries. (3)Mold growth was completely excluded for 5 weeks when stored under the presence of oxygen absorber. Oxygen absorber thus proved to be a good method for prevention of mold growth. (4)In the case of absorber was sealed in, formation of carbon dioxide and ethyl alcohol was observed in the confectionaries containing sweet bean paste of relatively high water activity. Yeasts were identified as the major origin. (5)Confectionaries of high water activity were deteriorated by yeast and bacterial growth even under the presence of oxygen absorber, therefore sanitary and microbiological control in the manufacturing process may be necessitated.

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A description of a new apparatus for the measurement of viscoelasticity of gel-like foods was given. Complex Young's modulus E^*=E′+iE″ of gels can be obtained easily and rapidly by means of this apparatus. E′ and E″ of agar-agar and gelatin gels were determined for various concentrations. E' of these gels were proportional approximately to the square of the concentration. The values of the mechanical loss tangent of gelatin gels were larger than those of agar-agar gels. Temperature dependence of E′ and E″ of gelatin gels were also examined. Force-deformation curves were obtained for these gels in the case of uniaxial compression with a constant speed. The breaking strength of gelatin gels was much larger than that of agar-agar gels. It was very difficult to obtain force-deformation curves for gelatin gels with good reproducibility. The breaking process of gelatin gels was recorded photographically at regular time intervals. It was concluded that the dynamic measurement in the range of small deformation is an appropriate method for evaluating the quality of gel-like foods.

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The Japanese radish roots subjected to pre-heating treatment prior to boiling process in water were harder than the corresponding untreated control. A maximal hardening was obtained at 55°C for about 2hr, and this temperature was identical with the optimum temperature of pectinesterase (PE)contained in Japanese radish. The degree of esterification of the pectic substances was found to decrease greatly during this pre-heating treatment. Of the total pectic substances, the water soluble fraction decreased while the hot water soluble and hydrochloric acid soluble fractions increased in hardned tissues, compared with the untreated ones. A large amount of potassium ion leaked out into the soaking water from the tissues during pre-heating treatment at more than 50°C, on the other hand, amounts of leaked calcium and magnesium ions was relatively small. It was suggested that pre-heating treatment caused potassium ion migration prior to activation of the PE which was inactive in an intact tissue, and the activated PE promoted demethylation of the pectic substances in the tissue to cause hardening by combination of the resulted free carboxyl groups in the pectic substances and divalent cations in the tissue.

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Soybean sprouts are used commonly as a nutritional food material in Japan. Seeds of soybean contain several kinds of trypsin inhibitor(TI). In order to know the periodical changes of TI activity in soybean sprouts during germination, seeds of soybean were germinated or 6 days and TI activity in cotyledon and axis, was determined. (1) TI activity in soybean sprouts was 67.1mg corresponding to 80-85% of that of soaked soybean. More than 99% of TI activity of soybean sprouts existed in cotlyedon and the rest was contained in axis. TI activity in cotyledon and axis at different stages of germination were determined. It was 70.2mg in cotyledon and 14.3mg in axis after 2 days of germination, 64.6mg and 0.83mg after 4 days of germination. Cotyledon contained 73.7mg of its activity but axis did not show any TI activity after 9 days of germination. The activity of TI is expressed as mg of TI in one gram of fresh soybean sprouts. (2) TI in soybean seed and soybean sprouts (cotyledon and axis) was fractionated by gel filtration with Sephadex G-75. TI in soybean seeds and cotyledon was fractionated into 2 peaks, TI in axis after germination for 2 days showed only one peak. However 2 peaks were observed in FI from an axis after germination for 4 days and seemed to be separated from TI of 2 day-old axis. (3) TI peaks obtained by gel filtration were further fractionated by chromatography on a column of DEAE-cellulose. Main TI was shown to be 8 peaks. TI in cotyledon of soybean sprouts became difficult to be separated clearly due to close distance of each peak with increase of germination days. TI in axis was only one peak for 2 days of germination but it become 2 peaks for 4 days. (4) Changes of TI activity in soybean sprouts by heating were studied TI activity in cotyledon was inactivated compleaty by treatment with boiling water for 5min, but TI activity in axis was still remained.

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Green soybean is widely consumed as "Edamame" (boiled green soybean)in Japan because of its characteristic taste and nutritional value. It is well known that mature soybean contains several kinds of trypsin inhibitors(TI), but a few paper were available about TI in green soybean. In order to know the changes of TI activities in green soybean during maturation, soybeans were harvested periodically from the plants cultivated for 111 days to 165 days. The results are as follows; (1)TI activity was not observed within 116 days of cultivation. TI activity was found in the soybeans harvested from 123 day-old plants. TI activity in the soybeans was measured during cultivation from 123 to 165 days periodically. The maximum TI activity was determined to be 17.9mg/g of fresh weight and specific activity was 168 in green soybean picked from 137 day-old plants seed length, 1.2-1.4cm. TI activity in green soybean increased with the growth of seeds; TI activity of green soybean of seed length 0.8-1.0cm was only 6.9mg/g of fresh weight, whereas, that of seeds of 1.0-1.2cm length was 14.7mg/g of fresh weight. (2)TI in soybean was fractionated by chromatography on columns of Sephadex G-75 and DEAE-cellulose. (i)TI in green soybean of seed length 1.2-1.4cm was separated into 4-6 TI peaks on Sephadex G-75 and main inhibitors were No.3 and No.4 peaks. TI activity ratio of No.3 and No.4 to total TI activity increased with cultivation period. TI in green soybean of short length(less than 1.2cm)was fractionated into six peaks and main inhibitors were also No.3 and No.4 peaks. (ii)TI of No.3 and No.4 peaks obtained by gel-filtration were further fractionated with a DEAE-cellulose column, The number of TI peaks in same length seeds tended to decrease with cultivation days. TI in the seeds of same size(1.2-1.4cm length)picked from 123, 159 and 165 day-old plants had 7, 5 and 4 peaks by column chromatography on DEAE-cellulose, respectively. (3)Changes of TI activity in green soybean by heating were also investigated. TI activity in green soybean obtained from local market was 19.7mg/g of fresh weight and decreased slightly to 13mg/g of fresh weight by the heat treatment at 100°C for 5min. TI in this heat-treated green soybean was fractionated into 9 peaks on Sephadex G-75.

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Rheological properties of soybean milk obtained from several tofu plants were examined by the use of a cone-and-plate viscometer. The flow curves of soybean milk exhibited non-Newtonian behavios and were approximated by pseudoplastic flow expressed as τ=K(D)ⁿ. The value of flow behavior index, n, was 0.59 to 0.66.

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The functional properties of 'Soba-kiri', or buck-wheat noodle, were investigated with respect to the added gluten content in the formulated flour as well as the ratio of buckwheat flour versus wheat flour. When gluten was added to the newly formulated flour composed of 90 parts of buckwheat flour and 10 parts of wheat flour at 10% level, its properties such as machinability, required cooking time and loss in cooking water were equivalent to those of the conventional formulated flour of the 50 to 50 ratio.

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