A convenient method of the multi-point mensuration method was applied to compare the texture of cooked rice in grain level. The convenient method used in this report is two points (50% and 90% deformation)mensuration method. Tensipresser reported previously was most suitable for this measurement. The ratio of the textural parameters measured at 50% compression to those at 90% compression could be used for relative comparisons of the texture of cooked rice. Especially, the ratio of adhesiveness to hardness measured at 50% compression and the ratio of adh./hard. at 50% compression to adh./hard. at 90% compression were the most useful indices in rating the textural property of cooked rice which related to the mouth feeling.

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The enzymatic conversion of cellulose in cryomilled newspaper has been investigated. X-ray diffractogram of the cryomilled waste cellulose to 250 mesh showed that it lost the crystalline structure. The degree of enzymatic hydrolysis of the cryomilled cellulose was about 60% at 72hr by Aspergillus niger cellulase containing mainly 1, 4-β-glucan glucanohydrolase without action of 1, 4-β-glucan cellobiohydrolase. Chemical pretreatments(alkali, acid or acetone)for the cryomilled waste cellulose were less effective to increase the degree of enzymatic hydrolysis and the residual substrate in 40% yield was resistant to cellulase. These results suggest that the biological susceptibility of the waste cellulose does not depend on the degree of crystallinity but relates to lignin bound to the alkali treated waste cellulose. A problem on the resistant cellulose to enzymatic hydrolysis in waste cellulose are discussed.

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Soymilk was treated with proteolytic enzymes, including ficin, bromelain, papain, rennet and pepsin to investigate their digestibility and coagulability. Coagulation of soymilk occured within a short time after addition of ficin and bromelain, but papain treated soymilk required too long time for coagulation. Rennet and pepsin had no coagulability. It was clear that heat treatment of soymilk at the temperature above 70°C, corresponding to the denaturation of soy protein, was essential for coagulation of soymilk by proteolytic enzymes. The coagulability of ficin and bromelain for soymilk rapidly decreased by heat treatment of each enzyme solution at temperature above 65°C. As the coagulation of soymilk resulted in proteolysis of soy protein, the recovery of protein in coagulants from soymilk was comparatively low at reaction temperature in the rangeof 40°-60°C. To improve the protein recovery, 1.0×10^-5 or 1.0×10^-6 mol calcium was added to soymilk with enzymes. Addition of calcium, however, had no effect on the coagulability and protein recovery. The lactic fermentation of soymilk by Streptococcus thermophilus considerably reduced coagulation time and increasd the protein recovery. In the manufacturing process of cheese like product with application of curd formation by lactic fermentation and addition of ficin or bromelain, the curds obtained had no bitterness and the percentage of protein recovery reached approximately 80%.

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This report describes the effects of the storage temperature on the shelf life and the quality of some kinds of mushrooms, "mushroom" (Agaricus bisporus Sing.), oyster mushroom(Pleurotus ostreatus(Fr.)), shii-take(Lentinus edodes(Berk)Sing.), nameko(Pholiota nameko(T. Ito)S. Ito et. Imai)and enoki-take (Flammulina velutipes (Fr.)Sing.). The shelf life of these mushrooms was about 14-20 days at 1°C, about 10 days at 6°C and 2-3 days at 20°C. It was found that the deterioration of mushrooms were caused mainly by opening and browning of the pilei, as well as elongation and browning of the stipes. Especially in "mushroom" and shii-take, browning of the pilei, gi11, and stipes and polyphenoloxidase activity were markedly developed during storage at 20°C. Higher respiration rate than that of other horticultural products was observed for harvested mushrooms as much as about 200-500mg CO₂/kg/hr at 20°C. Glutamic acid, asparatic acid and their amides were shown as the major components of free amino acids in each mushroom. Total free amino acid content increased in shii-take, nameko, or oyster mushroom during storage at 20°C.

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Sake, raw material for rice vinegar production, was prepared by the conventional koji process and enzymatic process employing a commercial enzyme preparation of fungal origin which possesses α-amylase, glucamylase, protease, and cellulase activities. The suitability of raw Sake made by the enzymatic process for rice vinegar production was compared with that of the conventional process. Results obtained were as follows: 1)General components in both raw Sake were almost same except that raw Sake made by the enzymatic process contained more total extract and amino acids than the conventional Sake did. 2)The yield of Sake cake from total rice was 22.9% by the conventional process and 18.0% by the enzymatic process. Sake cake obtained from the enzymatic process contained lower amount of organic components than that by the conventional process showing that the former process was superior to the latter in respect to the utilization of the rice constituents. 3)Acidity increase in vinegar mash by the enzymatic process was slightly faster than that by the conventional process when fermented by both static and aeration methods. 4)No marked difference was found in the chemical components between enzymatic processed vinegar and the conventional vinegars, but the result of sensory test showed that the quality of the vinegar by the enzymatic process was superior to that by the conventional process.

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It was reported that N-succinylation of egg yolk was effective for improving its emulsifying properties. To investigate this effect, egg yold LDL(Low Density Lipoprotein)and HDL(High Density Lipoprotein)were succinylated at three different degrees. While succinylated LDL showed almost the same turbidity as intact LDL, the viscosity of 87.5% succinylated LDL was 1.3-1.4 times as high as that of intact LDL. Emulsifying activity of LDL decreased by succinylation, on the other hand, emulsifying capacity and emulsion stability of LDL increased with an increase of the degree of succinylation. Succinylated HDL showed almost the same turbidity as intact HDL in 2% NaCl soln. The viscosity of 92.1% succinylated HDL was 2.0-2.4 fold over that of HDL. Emulsifying capacity of succinylated HDL hardly increased, but emulsion stability of HDL increased with an increase of succinylation.

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This report deals with chemical properties of pectic substances and compositions of cell wall polysaccharides from roots of four varieties of Japanese radish(Raphanus sativus var. hortensis)and their changes during drying and salting of representative radish roots consumed as raw materials of pickles. The polysaccharides of radish cell wall consisted of 36 to 38% of pectic substances, 23 to 29% of crude fiber and 9 to 12% of hemicelluloses. The pectic substances contained 76 to 85% of anhydrogalacturonic acid and 4.08 to 7.26% of methoxyl group. By DEAE-cellulose chromatography, the pectic substances were divided into six fractions whose main fractions were P-3 and P-4. The result of paper chromatography showed that P-2, P-3, P-4 and P-5 were composed of galacturonic acid, galactose, arabinose, xylose and rhamnose. Drying and salting had a great influence on the composition of cell wall polysaccharides and chemical properties of pectic substances. The total amount of pectic substances in dried radish decreased, while that in salted radish did not change. On the other hand, the crude fiber content increassed in both radish. The methoxyl group content of pectic substances in dried and salted radish markedly decreased. These results suggest the possibility that drying and salting may reduce the solubility of pectic substances. The main fractions from pectic substances by DEAE-cellulose chromatography were P-3 and P-4 in fresh radish roots, while those in dried and salted radish roots were P-4 and P-5.

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The organic acids in four cultivars of fresh radish and their changes in the process of making salted radish were investigated by a carboxylic acid analyzer. Fresh radishes contained malic, pyroglutamic, citric, glucuronic, acetic and succinic acids. The amonnt of malic acid was largest being followed by pyroglutamic acid. The pattern and content of organic acid in fresh radishes of four cultivars were almost same. During processing of salted radish, malic acid decreased, whereas pyroglutamic and lactic acids increased.

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Wasabon-to sugar has been manufactured in Japan by unique traditlonal refining procedures but the differences of the unique flavor among products of Wasanbon-to have not been studied previously. In the present paper analysis of variance of chemical components for Wasanbon-to was studied by F-test. The sugar cane pressed juice from Chikusha variety contained less free amino acids and reducing sugars but higher titratable acidity than did that from variety N:Co. The Wasanbon-to refined by manual processes contained less free amino acids, and more ash than that refined by centrifugation.

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