Gelation kinetics of powdered soybean dispersion in the presence of glucono-δ-lactone (GDL) was studied by dynamic viscoelastic measurements and differential scanning calorimetry (DSC). The gelation time became shorter and the rate constant of gelation increased with increasing concentration of soybean powder (11-17%) and GDL (0.2-0.5%) or heating temperature (40-90°C). Both storage and loss moduli increased with increasing concentration of soybean powder and GDL. The storage modulus as a function of heating temperature showed a maximum at 70°C for heated dispersion of powdered soybean. A non-heated dispersion of powdered soybean showed two endothermic peaks, while a heated dispersion of powdered soybean did not show any endothermic and exothermic peak in the temperature range studied by heating DSC (20-140°C). The peak temperature for a non-heated dispersion of powdered soybean shifted to higher temperatures with increasing GDL concentration. From the rheological properties it is suggested that a heated dispersion of powdered soybean formed a stronger gel with increasing concentration of soybean powder and GDL.

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We developed a new type apple juice containing partially enzymatic degraded pectin which is clarified through ceramic MF membrane, since the apple pectin is considered as a functional material being good for human health. The molecular weight of water soluble pectin (WSP) in original apple juice was approximately distributed in 20000 to 3000000. The higher molecular weight WSP in original juice showed the lower permeability through the MF membrane. It was considered that higher molecular weight WSP formed a fouling layer of a self-rejection type dynamic membrane on the MF membrane and inhibited the permeation of WSP.
Permeability of WSP on filtrating to volume reduction factor (VRF) 2.5 was only 5.7% on a basis of concentration. Therefore, higher molecular weight WSP was partially degraded by a pectic enzyme, of which molecular weight over 1000000 disappeared by the treatment at 20°C for 5min.
The permeability of WSP on filtrating to VRF 2.5 was largely improved to 55% on a basis of concentration by this treatment. The precipitation of pectin in the new type apple juice was not observed during 100 days storage at room temperature. It was demonstrated that the enzymatic partial degradation of pectin was a useful method to produce clarified WSP containing apple juice containing WSP treated with ceramic membrane.

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Texture descriptive terms were studied in Chinese. Three hundred and seventeen words were collected from a free answer questionnaire by laboratory panels in Beijing (capital; north area), Shanxi (north inland area), Shanghai (east coastal area) and Guangdong (south coastal area). From these 317 words 144 terms were selected as texture descriptive terms through round table discussion by an expert panel. Then 144 terms were studied with respect to their relationship to 30 kinds of conceptual parameters such as hardness, fracture, elasticity, particles and moisture. The evaluations were made in laboratory panels in Beijing and Shanghai. The panel members were asked to select conceptual parameters that each term describes. The data was analyzed through Quantification Method III and their item category score and sample score were obtained. The scores obtained in Beijing and Shanghai were approximately similar. The item category score showed that there are 6 fundamental concepts in texture expression in Chinese: “hardness”, “cohesiveness”, “viscosity”, “elasticity”, “brittleness” and “oiliness”. The 144 texture descriptive terms were classified into 53 groups on the basis of the similarity of their sample score.

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It has been observed in our daily life that the addition of soybeans to cooking solution promotes the softening of vegetables during cooking. In order to investigate the effect of addition of soybeans during cooking on the softening of vegetables, experiments were conducted, how to change the texture of carrots by the addition of soybean cooking solution or its fractions (drawing parts) during cooking. Centrifugal separation and ion exchange treatment of the soybean cooking solution were carried out. The effects of the addition of the soybean cooking solution and its fractions on the softening of carrot during cooking were investigated with regard to the properties of firmness and cohesiveness of texture. It was found that a large quantity of potassium was contained in the soybean cooking solution. Potassium salt promoted the softening of carrot during cooking. Potassium salt decreased the firmness of the carrots during cooking, but decreased little the cohesiveness. While the supernatant of the soybean cooking solution and the deanion fraction of it decreased both the firmness and the cohesiveness of carrots during cooking. Furthermore, it was suggested that there were some promoting factors besides potassium ion for the softening of the carrots during cooking in the supernatant of the soybean cooking solution, and that there were also some preventing factors for the softening of carrots in the decation fraction.

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A continuous flow-type reactor was constructed for examining the hydrolysis of Okara in subcritical water without catalyst. As a result of the experiment, it was possible to process Okara continuously in the equipment. We found that the water-soluble component of Okara was increased in subcritical water during a short reaction time. Though the water-soluble component has been composed of protein, non-cellulosic polysaccharide and cellulose, the proportion of the non-cellulosic polysaccharide increased much more than the others, when the reaction temperature rose. The water-soluble dietary fiber, whose main composition is non-cellulosic polysaccharide such as hemicellulose, was included for about 3 times for Okara processed at 290°C as much as that of Okara. Since the reaction residue, which does not dissolve in the water, swelled very much for the water and became like the soft gel, it is considered that the deterioration of the food feeling with peculiar Okara is prevented when it is added to the food.

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Studies on cell wall polysaccharides in ethylene treated mungbean sprout have mainly been focused on the hypocotyls at early growth stage. In this paper, the quantitative changes in cell wall polysaccharides of each part (hypocotyl, cotyledon, root and seed coat) of commercially produced mungbean sprouts were investigated and evaluated the characteristics of cell wall biosynthesis in each part. Although fresh weight of both hypocotyl and root increased as the plants grew in darkness, the growth of hypocotyl was far bigger than that of root. Total uronic acid concentration in pectic substances increased in both hypocotyl and root within 3 days after ethylene treatment, while it increased thereafter in cotyledon. In hypocotyl, uronic acid concentration increased rapidly in water- and HCl-soluble fractions between the days 3 and 5, while neutral sugar concentration retained a low level or rather decreased. In root, a rapid increase in uronic acid concentration was detected in both EDTA- and HCl-soluble fractions, while neutral sugar concentration retained a low level during the experiment, irrespective of pectin sub-fractions. These results suggest that, when mungbean sprouts grew, the activity of the biosynthesis of main chain of water- and HCl-soluble pectin polymers were higher than other fractions in hypocotyl, while the activity of the biosynthesis of main chain of EDTA- and HCl-soluble pectin polymers were higher than other fractions in root.

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To gain further information on physiological functions of citrus auraptene (Aur), either dried powder of the peel from amanatsu (Kawano natsudaidai, Citrus natudaidai) abundant in Aur or the Aur concentrate prepared from the rind were fed to rats in separate feeding trials. The serum components and the hepatic fatty acid compositions were analyzed. The concentration of serum triglyceride tended to decrease in the groups of rats fed Aur in both experiments. This was not reproduced in rats fed the peel from Ponkan citrus (Citrus reticulata) poor in Aur. In addition, in fatty acid composition of liver phospholipids, the proportion of linoleic acid decreased, while that of arachidonic acid increased after feeding Aur, suggesting a raise in the desaturation rate for linoleic acid. These results indicate that Aur characteristically modifies fatty acid metabolism, and in particular the change in polyunsaturated fatty acid pattern may indicate changes in eicosanoid production. Thus, Aur may possibly have diverse physiological functions other than the anti-carcinogenic potential hitherto evidenced.

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Major manufacturing problem of the boiled-dried adductor muscle of scallop (Shiraboshi) is long periods for the manufacturing and limitation of the fishing season of the scallop. We suggested that the superheated steam is useful on Shiraboshi manufacturing being a very effective method to shorten the manufacturing period and to produce the high-quality product. As the following result were obtained. (1) The manufacturing period is drastically shortened. (2) On degree of browning which influences the quality of Shiraboshi, the product with first-class quality is produced. (3) The water dipping over 15 minutes of the product prevented crack in body of the product in drying process. However, when the product was soaked in the manufacturing process in alkali aqueous, there was the decomposition of the nucleic acid related compound, (4) Nucleic acid and glycogen which are related to the palatability of the product were remained in high level.

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Differences in the concentrations of free amino acid and sugar in immature seeds harvested 35 days after flowering of nine vegetable-type soybean (Edamame) and five grain-type soybean cultivars, and changes in the component of free amino acids and sugars in seeds after bioling for 3min. were examined. The concentrations of total free amino acids largely varied among cultivars. The concentrations of the total free amino acids were highest in the seed of Shirayama-dadacha (11.0mg/gFW), and followed Sapporo-midori, Aobata and Kahori. On the free amino acids examined, major component in the immature seeds Shirayama-dadacha were glutamic acid, asparagine and alanine and the component of the these three amino acids were almost 50% per total amino acids. After boiling, avarage concentration of total free amino acids sharply decreased to 74%. The concentrations of the total sugar and sucrose were highest in the immature seeds of Shirayama-dadacha that contain 47 and 30mg/gFW, respectively. The concentrations of the total sugar and sucrose were also higher in vegetable type cultivars, Aobata and Hiden. After boiling of immature seeds, average concentration of total sugar elevated 1.5 hold, although the concentration of sucrose was unchanged.

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Conversion rate of chlorophyll into pheophytin (Phy conversion rate) and hydrogen ion concentration (pH) in fresh and crude tea leaves and the relationship between them were investigated to elucidate the reason why the second crop of tea is more liable to color change from the green of tea leaves into yellow-brown than the first crop of tea. It was proved that in the second crop of tea leaves the pH was lower, but the Phy conversion rate was higher as compared to the first crop ones. Furthermore, there was a relatively strong negative correlation between the Phy conversion rate and pH. It is well known that the lower the pH is the higher the Phy conversion rate. These results suggested the liability for the color change of second crop of tea would be explained by the higher Phy conversion rate based on the lower pH.

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The fermented citrus peels with high antioxidative activity were prepared by fermentation of lemon, orange and grapefruit peels with three species of genus Aspergillus (A. awamori, A. niger and A. usamii mut. shirousamii). They showed higher DPPH radical-scavenging activity in comparison with citrus peels before fermentation. Flavonoid aglycones and hydroxyflavonoids such as 8-hydroxyhesperetin and 8-hydroxynaringenin were produced in the fermented peels. The increase in antioxidative activity of the fermented citrus peels was suggested to be attributed by the production of hydroxyflavonoids.

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