Proteolytic and milk clotting activities of the culture filtrate obtained from 82 strains of Basidiomycetes were investigated.
A large number of strains of Aphyllophorales showed high proteolytic activity on casein at pH 3, whereas almost all strains of Agaricales had only slight activity. On the other hand, when the activity was measured at pH 6, the proteolytic activity of Aphyllophorales decreased in some degree, but the activity of some strains of Agaricales was high.
It was revealed that the ratios of proteolytic activity at pH 3 to proteolytic activity at pH 6 of Aphyllophorales were, in general, more than 1.0, whereas those of Agaricales were below 1.0. Therefore, it was suggested that the strains of Aphyllophorales chiefly produced acid proteinases and that some strains of Agaricales some neutral or alkaline proteinases. Coprinaceae produced alkaline proteinase with optimum pH 8.5_??_9.0 on casein.
As the enzymological properties such as optimum pH, pH stability, thermo-stability and so on were similar, it was assumed that acid proteinases of Basidiomycetes were not very different from one another, although they had different values of isoelectric point.
As for milk clotting activity, it was suggested that certain acid proteinases produced by Basidiomycetes might be used for a rennet substitute, but a few strain produced the enzyme with both high MCA and MCA/PU values.

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Distribution of yeast cell lytic, β-1, 3-glucanase and chitinolytic activity among the 82 strains of Basidiomycetes was investigated.
At pH 4, some strains of Aphyllophorales decomposed both lyophilized and heated yeast cells (Saccharomyces cerevisiae) fairly well, whereas Agaricales had no activity. On the contrary, when the activity was determined at pH 7, strains of Aphyllophorales were able to decompose only heated cells and those of Agaricales exhibited high activity against both lyophilized and heated cells. Especially, Coprinaceae decomposed heated cells to a great degree at pH 7.
As for β-1, 3-glucanase, some strains of Polyporaceae, for examples Gloeophyllum saepiarium, Trametes sanguinea, Irpex lacteus and so on, produced a large quantity of the enzyme in a medium. It seemed that β-1, 3-glucanase is produced universally by Basidiomycetes. On the other hand, chitinolytic activity of Basidiomycetes is low.
Since there was a big difference between a distributional pattern of yeast cell lytic activity and that of β-1, 3-gluacanase or chitinolytic activity, and since both β-1, 3-glucanase and chitinolytic activity of Coprinaceae were not always high, it was supposed that high yeast cell lytic activity of Coprinaceae mainly came from an alkaline proteinase with optimum pH 8.5 to 9.0 on casein.

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Further studies with Candida lipolytica revealed that there exists a definite relation-ship between citrate fermentation and cell propagation.
When the culture medium containing no neutralizing agent was employed, the amounts of yeast cells increased, accompanied by the decreased amounts of citrates. In such cultivations, yeast cells increased in weights rather than in numbers.
The abundant supply of oxygen was essential to the effective production of citrates as seen before. When insufficient oxygen was supplied, the speed of citrate fermentation was lowered and true, septate mycelia developed markedly. At the same time, it was confirmed that aeration was the sole factor in this dimorphism.
At a rather high temperature of 35°C, the yeast could grow abundantly and produce citrates in glucose medium, while it could not grow in n-paraffins medium.

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Previously, the present authors had shown that many yeasts produced a large amount of citric and d-isocitric acids from glucose as well as from n-paraffins when the culture medium containing neutralizing agent was employed. It was also proved that, in such conditions, a small amount of polyhydric alcohols was detected temporarily at the early stages of citrate fermentation in Candida lipolytica, and that, on the contrary, when the culture medium containing no neutralizing agent was employed, the amount of polyhydric alcohols increased, accompanied by the decreased amount of citrates. In some extreme cases polyhydric alcohols were produced in the yield of 30 per cent on the basis of n-paraffins supplied. Polyhydric alcohols consisted mainly of mannitol, together with small amounts of arabitol in glucose medium or of erythritol in n-paraffins medium.
A variety of yeasts produced also polyhydric alcohols, mainly pentitol, from petrochemicals.

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The free sugars of A. victorialis L. were extracted by conventional methods, fractionated by charcoal-celite column chromatography, and further separated by preparative paper chromatography. D-Fructose, D-glucose and sucrose and, in addition, neokestose and 1-kestose, which are trisaccharides with chemotaxonomic interest, were confirmed by paper chromatography and further by gas chromatography of O-trifluoroacetyl derivatives on Silicone DC QF-1, OV-17 and SE-52.
From comparison of the free sugar contents in several Allium species (A. victorialis L., A. fistulosum L., A. tuberosum L., A. cepa L. and A. sativum L.), the significant differences were recognized in the case of disaccharide (sucrose) and trisaccharides (neokestose, 1-kestose and P-6).

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Pectic polysaccharides were extracted from cotyledons of kidney beans under conditions designed to prevent the degradation of pectic substances and separated into a fraction of neutral polysaccharides and those of weakly acidic pectinic acids containing 12.5 to 35.3% of galacturonic acid. Some of the latter fractions were hardly degraded by polygalacturonases, while the rest of the latter were susceptible to the same enzyme though the values of degradation limit were considerably low as compared with those of commercial pectic acids. It was found that polygalacturonase-resistant galacturonosyl residues in the molecules of the weakly acidic pectinic acids are partly esterified by methyl groups. Strongly acidic pectinic acid, the main component of cambium and callus tissue pectins, is probably absent erom the pectin of kidney bean cotyledons. In contrast, the neutral polysaccharide component is present in extraordinary large amount.

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Turbidity measurements were made with skimmed bovine milk to obtain information about the influence of pH change on casein micelles. When the pH of skimmilk was dropped from 6.8 to 5.7, a considerable decrease of turbidity was observed. Further decrease of pH induced a turbidity increase due to the aggregation of micelles. The turbidity decrease was promoted by addition of sodium chloride and prevented by addition of calcium chloride. Measurements of pellet volume, viscosity and sedimentation indicated that casein micelles shrinked at pH 5.8 to about 3/4 of their original volumes. No significant change of protein concentration was observed in the milk serum at this pH. It was concluded that the turbidity decrease was brought about through the liberation of calcium from micelles. The pH of the micelle aggregation was found to depend on the calcium concentration and the higher the calcium concentration the lower the pH of aggregation. An assumption was proposed that a disturbance of micelle structure caused by the liberation of calcium should be a necessary step for the formation of intermicellar bonding.

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Textural qualities of sponge foods were evaluated organoleptically and 5 fundamental textural characteristics and the sensory parameters corresponding to each characteristic were established as follows; characteristic I hardness and/or chewiness (primary parameter “hard-soft, ” secondary parameter “crumbly-not crumbly”), II viscosity (primary “viscous-not viscous”), III wetness (primary “dry-wet”), IV oiliness (primary “oily/greasy-not oily/not greasy”) and V fineness (primary “coarse-fine”).

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Textural qualities of porous rigid foods, such as biscuit, cookie, cracker, rice cracker etc., were evaluated organoleptically. Five fundamental textural characteristics of porous rigid foods and the sensory parameters corresponding to each characteristic were established as follows; characteristic I hardness and/or chewiness (primary parameter “hardsoft, ” secondary “crumbly-not crumbly”), II adhesiveness (primary “sticky-not sticky”), III wetness/moistness (primary “dry-wet”). IV oiliness (primary “oily/greasy-not oily/not greasy”) and V fineness (primary “coarse-fine”). In addition to these descriptive scales, the onomatopoeic words “kari-kari” (crisp) and “boro-boro” (crumbly) were also effective in describing the texture of porous rigid foods.

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