Effectiveness of a process by microwave heating with flowing air for drying of sliced potatoes were examined. Sixty pieces of sliced potatoes (diameter 40mm, thickness 5mm, water content 85%, weight 6.5g/piece) were dried by using microwave apparatus (0-400W) and flowing air (temperature 10-90°C, flow rate 0.8m/s) in a draft cavity. Gelatinization of starch grains and case-hardening caused during the drying process were investigated by a microscope. Rehydration of the tissues of dry potatoes obtained by the processing were examined. (1) The sliced potatoes were dried upwithin 2h by flowing air of 90°C at the rate of 0.8m/sec. In this case, the quantity of water rehydrated to the tissues of potatoes was significantly decreased, and gelatinization of starch and the case-hardening caused on their surface. (2) It took long time more than 24h to dry the sliced potatoes by flowing air of 30°C. In this case, no gelatinization of starch grains was found and rehydration of their tissues were finished within 3h. (3) By using microwave energy of 150W with flowing air of 30°C, it took only 2.5h to dry up them, and they were much uniformly dehydrated. As some spaces were left between their starch grains, their rehydration time were much reduced to less than 1h.

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The cause of occasional insufficient fermentation of pickling turnips was examined. Twenty-eight point seven percent of bacteria isolated from turnips had nitrite-producing ability, and the dominant flora were Pseudomonas and Enterobacteriaceae. The growth of strains Pseudomonas were not inhibited by nitrite at pH 6.4 and the strains Enterobacter were slightly inhibited, although they were appreciably inhibited at pH 5.0 which is the pH value of fermented pickles. The growth of strains Leuconostoc were also appreciably inhibited by nitrite. It was concluded that the growth of lactic acid bacteia was inhibited by the excessive concentration of nitrite produced by nitrite producing bacteria at the beginning of the fermentation of pickling turnips.

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Bovine plasma proteins were fractionated by the COHN's method, which has been used world-wide to produce plasma fractions. The separation of plasma into fractions concentrates most of fibrinogen in, Fr-I, of globulin in Fr-II+III, and of albumin in Fr-V. The interaction among myosin B, whole plasma, Fr-I, Fr-II+III and Fr-V was examined by measuring the changes in turbidity of a solution and SDS-PAGE. When the time course of turbidity was measured at pH 6.0 in the presence of 500mM NaCl by heating at 1°C/min from 30°C to 100°C, the turbidities of plasma, Fr-1, Fr-II+III and Fr-V were sharply increased from 73°Cto 82°C, from53°C to 63°C, from 70°C to 76°C and from88°C to 96°C, respectively. SDS-PAGE showed that plasma proteins were able to bind to myosin B, especially to myosin: and actin. The interaction between myosin B and fibrinogen was stronger than those between myosin B and globulin or myosin B and albumin.

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To examine the differences in sugar contents of soybeans cultured by upland and drained paddy field, the contents of total sugar, free type of total sugar, and free sugars were estimated with 78 seed samples of 31 cultivars grown at 5 Agricultural Experiment Stations in 1980. The drained paddy field culture, as compared with the upland culture, gave high total sugar, free type of total sugar, sucrose, and galactopinitol B contents (group 1 sugars), and low pinitol, glucose, galactopinitol A, raffinose, and stachyose contents (group 2 sugars). The cultivars early type and belonging to the line of Tokachinagaha, Nemashirazu, Shiroge 9, Nezumizaya, and Takiya, however, showed different tendencies from the abovementioned change, i.e. a decrease of group 1 sugars and an increase of group 2 sugars except galactopinitol A by the drained paddy field culture. From these results, it was deduced that the contents of the total sugar, free type of total sugar, sucrose, raffinose, and stachyose were influenced by cultivar, whereas the galactopinitol A content by cultural condition.

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The unique elastic texture of kamaboko, which is known as "ashi", is one of the most important factors to evaluate quality of kamaboko. Since ashi can bejudged only by mechanical factors such as firmness, toughness, shortness, chewyness etc., no objective measurement for evaluating ashi has yet been established. In this study, we examined the relationship between an organoleptic evaluation and rheological measurements of kamaboko. (1) Results of an elongation test showed that the product of the breaking stress and the breaking elongation-ratio correlates with toughness of ashi. Elongation curves of kamabokos which were pre-incubated (suwari) before heating and those of Odawara style were concave. Generally, kamabokos which showed a straight type of force-deformation curve were of good quality. The Mooney-Rivlin plots for kamabokos which were subjected to suwari showed straight lines. (2) Results of a compression test showed that the quotient of the breaking stress divided by the breaking compression-ratio relates with firmness but Young' s modulus is not closely related to hardness of kamaboko. (3) It was found that the loss modulus of not-chewy kamaboko was remarkably small. Although we could not characterize the quality of ashi completely by only mechanical parameters, the analysis of force-deformation curve pattern led us to roughly distinguish quality of kamaboko. The curve pattern could be a clue to the quality evaluation of kamaboko.

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Rheological properties of sponge cakes made from equal amounts of wheat starch, surose and whole eggs (starch cake) were compared with those of cakes made from equal amounts of wheat flour, sucrose and whole eggs (wheat cake). Loaf volume of starch cake was larger that of wheat cake. Cubes cut out from the sponge of cakes were subjected to rheological studies as test pieces. The cube of starch cake pressed into a tenth of thickness was recovered to the initial thickness when the load was removed. In the contrast, the cube of wheat cake pressed into less than 40% of the original thickness gave less recovery from the deformation. However, only a slight difference of the recovery of thickness was found between the two when pressed into a half of thickness. The creep profiles of wheat cake and starch cake were discussed.

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Effect of several compounds known as lipoxygenase inhibitors on the enzyme activity in soybean homogenate was examined. Among 10 compounds added at a homogenizing process, dithiothreitol decreased lipoxygenase-1 (L-1) and lipoxygenase-2 and/or-3 (L-2/3) activities to 68.8% and 19.2 %, respectively. Ethylenediaminetetraacetic acid (EDTA), CaCl₂, and ascorbic acid decreased L-2/3 activity to 36.3-52.2%, and did not change L-1 activity. Soluble protein content remained at the level from 21.4 to 24.1%, while that of control was 23.2%. Since it is reported that lipoxygenase-2 is responsible for the off-flavor of soybean products, the inhibitory effect of ascorbic acid on L-2/3 activity might be useful in soybean processing.

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The presence of anti-T (Thomsen-Friedenreich antigen) antibody in bovine milk and fetal bovine serum was demonstrated by an enzyme immunoassay using asialoglycophorin as an antigen. A high level of anti-T antibody was detected in bovine milk but not in fetal bovine serum. The reactivity of anti-T antibody in bovine milk decreased by heat treatment, suggesting the effectiveness of pasteurization for inactivation of anti-T antibody.

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In order to utilize Satsuma mandarin peel residue effectively, which contains many useful compounds, the method of extraction and recovery of hesperidin from dried Satsuma mandarin peel residue was studied. The results obtained were as follows; (1) The hesperidin content in a extracted solution was the highest, when the residue was extracted for 30 min with stirring at 20-40°C. (2) The optimum pH for crystallization of hesperidin from the extracted solution was around 5.0. And the recovery became much higher by heating the solution adjusted to pH 5.0 in the range of 70-90°C. (3) Therecovery yields were remarkably influenced by the quantity of added water to the residue. The best result was obtained by adding 800ml of water to 100g of the sample. In this condition, the recovery and purity of hesperidin was 27.3% and 93.7%, respectively. (4) To recover hesperidin effectively, it is necessary to adjust the hesperidin content in the extracted solution to approximately 500mg/100ml. Also, a higher yield (53.0%) was obtained by recycling the secondary extracted solution after concentration.

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The thermal gelation of sardine and Alaska pollack muscle proteins treated with high pressure was studied by means of temperature (40°, 50°, 60°, and 70°C)-jelly strength and thermal denaturation of actomyosin ATPases. The pressure treatment enhanced thermal jelly strength of meat and myosin pastes all over the temperature tested. The enhancing effects on both meat and myosin pastes were 1.3-1.6times at 200 or 500atm for sardine and about 1.5 times at 3000atm for Alaska pollack. The thermal denaturation (30°C) of the actomyosin Ca-ATPase was suppressed by pressure treatment (200 and 500atm). But for the Mg-ATPase the thermal activation was observed regardless of pressure treatment.

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In the trial to develop various methods for utilization of minced fish, a new fish product with plastic consistency was manufactured from enzyme-treated minced fish and palm oil. By the sensory evaluation of texture, our new fish product was evaluated to be fairly similar to processed cheese. The quality of our product depended mainly on its texture. Therefore the texture of our product was investigated rheologically. In the creep and recovery measurements, our product appeared to have plastic (non-recoverable) properties in instantaneous and retarded parts while processed cheese appeared to have plastic property only in instantaneous part. In the stress relaxation measurement, the relaxation modulus of our product decreased very quickly. These results mean that the structure of our product was easily broken down during the measurements. In the plunger penetration test of our product, the large drop of force after the first peak of the force vs. deformation curve, was not observed. Though this curve was steep at the origin and the instantaneous modulus was large in our product, the jelly strength and the breaking deformation were small. These properties of our product were similar to those of processed cheese, and quite different from those of kamaboko. However, the structural breakdown was more remarkable in our product than in the processed cheese, in creep and stress relaxation measurements and also in plunger penetration test.

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