The effects of melting point of palm oil on the gel formation from the soybean protein and on the texture of the gel were investigated. Hardness of the gels containing high melting point palm oils (33° and 40°C) increased with an increase of the oil content, but that of the gel containing low melting point oil (21°C) decreased with the oil content. Water holding capacity of all gels increased linearly proportional to oil content and the larger increasing ratio was observed for the gels containing higher melting point oil. Gelling rates of all gels decreased with an increase of the oil content, but the difference in the rate was not clear among the gels. Larger the oil content, the increasing rate of viscosity of each soy milk during heating at 50°C was lower, but its maximum viscosity value was larger. There was no difference among the maximum viscosity values of the soy milks concerning melting point of oils. Almost all oils were incorporated into gels up to the content of 15%. The electron microscopic observation revealed that oil seems to bind with protein weakly or to float in the network of protein as oil droplets of 7 to 10μm in diameter, and that the oil droplets of the samples containing higher melting point oils appear to be smaller than those of the samples containing lower melting point oils.

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Researches in the multi-biting test for homogeneous and heterogeneous liquid samples were carried out. Glycerol, soluble dextrin, ethyleneglycol and CMC solutions were used for homogenous liquid samples, and the pastes of potato starch were used for heterogeneous liquid samples. Negative and positive mechanical work loads of the plunger in the multibiting test of the liquid of various concentrations were analysed. In the test of homogeneous liquid, negative work load of the plunger in the multi-biting test of liquid correlated significantly to the viscosity of liquid. Ratio of the total negative work load to the total positive work load of the plunger vs the concentration of liquid showed a linear relationship within a certain range of the concentration. In the case of heterogeneous liquid, positive work load of the plunger corresponded to the apparent springiness characteristics of liquid. By suppressing the gel formation of starch pastes by adding 0.5% phosphoric acid, positive work load of the plunger in the multi-biting test of starch pastes decreased greatly, indicating the same physical properties of homogeneous liquid. Total of the negative work load of the plunger (10 bites) in the multi-biting test of various concentrations of starch pastes which had the spinnability characteristics, showed quite similar values to the index of adhesiveness of these starch pastes.

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An extracellular konjak-glucomannan decomposing enzyme produced by Bacillus circulans No. 215 was present in broth together with sugars derived from konjak. To purify the enzyme, the ordinary methods, e.g. gelfiltration and ion-exchange chromatography did not give good results. Therefore, we perfomed an affinity chromatography, using a column containing a specific adsorvent, konjakgel. The method permitted 97% exclusion of contaminating sugars from the crude enzyme fraction, and elevated the specific activity to 42.0 folds as compared with its crude extract. The partial purified enzyne degraded konjak, however it did not show the activity toward synthetic substrates, pnitrophenyl-α-Dglucopyranoside, pnitrophenyl-β-Dglucopyranoside, pnitrophenyl-α-Dmannopyranoside and pnitrophenyl-β-Dmannopyranoside.

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The textured whole soybean product (TWSP) has been produced by using a disk type of refiner devised by us. This product contains many useful components transferred from whole soybean as a starting material for human health and can blend well with a variety of other flavours and food materials. Oligosaccharides such as raffinose and stachyose in whole soybean have been known to cause flatulence. We could remove the oligosaccharides from TWSP by washing with water without detectable loss of protein and fat. The amounts of raffinose and stachyose decreaSed from 0.96% to 0.14% and from 4.9% to 0.7%, respectively, by washing with water for five minutes. We have also succeeded to make TWSP free from the oligosaccharides by washing before drying the product, during the process of the production of this product.

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Spun protein fibers which may be acceptable as meat analogues have been fabricated from antarctic krill (Euphausia superba) muscle proteins and Na-alginate. Through the use of column chromatography, the interaction between actomyosin, extracted from antarctic krill muscle, and polysaccharides were investigated. Of the polysaccharides tested, only Na-alginate reacted with actomyosin. Elution patterns of the reaction mixtures of actomyosin and Na-alginate were different from that of the individual component. No apparent effects of Naalginate on the elution patterns of globular proteins such as bovine serum albumin and apo-ferritin were observed. Elution pattern of antarctic krill muscle proteins mixed with Na-alginate was different from that of the antarctic krill muscle proteins only. It appeared that complex formation between antarctic krill muscle proteins and Na-alginate contributed to the fiber formation when the homogenous antarctic krill muscle proteins-Naalginate mixture was extruded into the coagulation solution containing Ca ion.

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Sorption, permeation and diffusion of volatile compounds have been studies under a nitrogen stream containing an organic vapor with polyethylene (PE) films with massfraction crystallinity from 0.49 to 0.64 and ethylene vinylacetate copolymer film. The volatile compounds used were n-alkanes, aliphatic ethyl esters, n-aldehydes and n-alcohols containing 4-12 carbon atoms. The semilogarithmic plots of diffusion, permeation, solubility coefficient against the carbon number in any homologous series gave linear relationships up to the compounds with 10 carbon atoms. The slopes of straight lines for sorptions ranged from 0.43 to 0.58. This revealed that the sorption into PE film caused the marked changes in composition of flavor components. Furthermore, the effects of crystallinity and molecular structure of PE on diffusion, permeation and sorption were also discussed.

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