Polysaccharides in miso are dirived from soybean except starch originating in rice koji. Since these soybean polysaccharides consist of much pentoses which easily reacts with amino acids resulting in browning, they have been considered to affect highly on coloring of miso. Changes of the polysaccharides during fermentation of miso was investigated. Although boiled soybean polysaccharides consist mainly of glucose, galactose and arabinose as major sugar, only galactose showed remarkable decrease resulting in the reduction of pectic substance by about 50% in miso. The polysaccharides of 2% level in miso were composed of 16% pectic substance, 28% hemicellulose and 56% cellulose. Rice koji enzymes for miso manufacting split mainly galactose but slightly pentose from soybean polysaccharides. Therefore it was assumed that the rice koji had weak endowise enzymatic ability for bound arabinose. This fact leads to the conclusion that the coloring of rice miso is slower than that of soybean miso made from soybean koji consisting of strong endwise activity. The water soluble polysaccharides of 0.35% level in miso contained high quantity of pentose as the result of spliting a part of sugar component of the polysaccharides in soyben during fermentation. Starch in miso decreased drasticaly at early stage of fermentation and disappeared in 50 days at 30°C. Galactomannan was detected at higher ratio in the polysaccharides of soybean steamed waste water than that in soybean boiled waste water.

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As free sugars in rice miso are derived from oligo-and poly-saccharides in rice koji and soybean by enzymatic hydrolysis, the composition is very complicated. Changes of these sugars during miso fermentation were investigated by liquid chromatography. The amount of monosaccharides was extremely high in the free sugars of miso, 70-80% of which is glucose, being followed by iso-maltose, galacturonic acid and fructose in this order, whereas the amount of pentose such as arabinose and xylose was very low. Free oligosaccharides were mainly composed of glucose and galactose, suggesting the existence of α-1, 6-gluco-saccharides from rice koji and galacto-oligosaccharides from soybean. Remarkble changes of free sugars were observed at the early stage of fermentatin. Glucose increased drastically as the result of the hydrolysis of rice koji starch and iso-maltose also increased, whereas maltose and sucrose decreased rapidly. At the middle stage of fermentation, glucose was consumed through fermentation by yeast decrease. Through all the fermentation period, galactose and mannose increased, stachyose decreased gradually and galacturonic acid showed little change.

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A precise method of analysis has not been established yet, as for the determination of water contents in some fermented products such as soy sauce and wine. The Karl-Fischer automatic moisture titration method was applied to the determination of water in these products. The apparatus employed in this paper, consisted of so-called closed system in which the atomosphere was kept dry with silica-gel, and was equipped with an automatic burette and also an end-point buzzer indicator. After placing approximately 20ml of formamide-methanol mixture reagent in the titration vessel, the Karl-Fischer reagent was titrated to the end-point. Then accurate quantity of soy sauce (25-50μl), wine (25μl), or dehydrated soy sauce (300-500mg) was put into the vessel and the titration was again brought up to the end-point. As the results of these experiments, it is concluded that the recoveries of water from soy sauce and also from wines were almost satisfactory. According to the present method, the water content in soy sauce and wines indicated 71-82%, w/v and 77-89%, w/v, respectively. On the other hand, the water content of dehydrated soy sauce tested, was in the range of 1.6-2.5%, w/w. In the case of the last products, however, the precise water determination seemed to be difficult for the lump or coasely granulated sample.

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Skim milk was separated from bulk cow's milk secured from a dairy district in Miyazaki prefecture, and was heated at 85°C for 5min, immediately followed by heating at 135°C in a moment. The effects of Ca and casein micelle on the physical properties (hardness, breaking energy and elastic modulus) of the rennet curd prepared from this high temperature heated milk were investigated by the use of a rheometer. The results obtained were summarized as follows: (1) The physical properties of the high temperature heated milk rennet curd could not be estimated under the experimentel condition employed in this study. (2) An addition of only Ca salt had a little effect on the rennet curd: The physical properties of rennet curd were maximal by the addition of 80mg Ca/100ml, but these were significantly inferior to those of unheated milk because of the heat denaturation of milk proteins. (3) The physical properties of rennet curd of high temperature heated milk could be remarkably improved by the addition of casein micelle (880mg N/100ml). When the unheated casein micelle ratio which was defined as a ratio of added casein micelle against the total casein micelle was 0.3, the rennet curd of high temperature heated milk could attain the physical properties almost the same as those of unheated one due to the increase of native micellar casein in high temperature heated milk. (4) Addition of micellar casein to the Ca-added (80mg/100ml) milk gave a remarkably strong rennet curd. At O.05 or 0.1 of the unheated casein micelle ratio, the physical properties of the prepared rennet curd were comparable to those of unheated milk. (5) From those results it was confirmed that the increases of soluble Ca and native micellar casein were essential for the improvement of rennet curd of high temperature heated milk.

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Free amino acids and amino-nitrogen contents in the juices made from Bartlett pears, most of which were grown in Yamagata prefecture, were determined. Results were as follows: (1) Generally, the fruits harvested at later period than that of proper harvesting or the overripened fruits after harvest contained less amounts of amino-nitrogen. However, no significant difference was observed in amino-nitrogen contents among the variations of fruit size. (2) No change was found in amino-nitrogen content through the storage for 7-21 days at 2-4°C. (3) It is significant that about 50% of the pears taken from a commercial juice factory showed 7-12mg% of amino-nitrogen and only 13% of them contained 16mg% or more, whereas the level of Japanese Agricultural Standard level for pear juice is 16mg% or more. Consequently, the revise of standard level for pear juice is to be needed further investigation. (4) The amino acids in Bartlett pears were asparagine (57%), aspartic acid (17%) and glutamic acid (8%). (5) Glutamic acid decreased as maturity progressed, and relatively high correlation (r=0.9304) was obtained between glutamic acid contents and the hardness of fruits.

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An effective method on saccharification of rice hull hemicellulose which contained xylose was studied. An extraction of Glucoxylan from rice hull with alkali solution gave a low value of about one fourth recovery, however lignin in the extracted solution was recovered easily by 75-95% acetone fractionation. Xyloglucan in rice hull was hydrolyzed effectively and almost completely by HCl than H2SO4. The Glucoxylan hydrolysis by 0.1 N HCl, 120°C, 2 hr. gave the mixture of 14.5% xylose and 6.7% glucose which was crystallized after purification. This result indicates that rice hull contains about 21% Glucoxylan which is composed of approximately xylose 2: glucose 1.

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The content of total phenolics in KÕshu white wine was reduced from 310 to 135ppm (gallic acid equivalent) by treatment with 15g of polyvinyl-polypyrrolidone (PVPP) per liter of wine. The latter was nearly minimum value. The phenol-reagent-positive compounds remaining in the wine treated with PVPP were isolated into five main fractions by gel filtration on Sephadex G-10 column with 3.0% acetic acid (pH=2.50) and then distilled water as the eluents. The fractions were respectively identified as flavanol tannin, fructose and glucose, xanthine, tyrosol and a mixture of three cinnamic acid derivatives by paper chromatography, ultraviolet absorption spectra, color reaction, etc. Concerning the coloration by phenol reagent, percentages of those fractions in the wine treated with PVPP were 4.4, 21.6, 18.1, 30.6 and 9.4%, respectively.

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Thirteen varieties of sour oranges, Citrus junos, G. tagumasudachi, Mukakuyu, Ohyu, Beniyu, Yuko, C. sudachi, C. kabusu, Sumikan, Kiyooka daidai, Tokosu, C. ujukitsu and C. tachibana, and C. unshiu (Satsuma mandarin) were used for the determination of organic acids, sugars, pectin and ascorbic acid. (1) The yields of juices from Tokosu, Mukakuyu and Yuko exceeded 30%, while those from C. junos, Sumikan and C. ujukitsu were as low as around 20%. (2) Among 9 to 15 peaks detected on the chromatograms, citric and malic acids were identified as the major organic acids, and lactic, acetic, formic, pyruvic, fumaric and t-aconitic acids were identified as the minor ones. The combined concentration of citric and malic acids amounted to 4 to 6% in most of sour oranges. (3) The sour taste of sour oranges might be classified by the reciprocal value of sugar acid ratio. The values of Mukakuyu, C. junos, C. sudachi and Ohyu were more than 20, and those of Kiyooka daidai, C. kabusu, Yuko, C. tagumasudachi, Tokosu and Sumikan were 10 to 20 on the basis of C. unshiu (1.0). (4) Ascorbic acid was contained as much as 40mg% in most of the sour oranges, especially 62.5mg% in Ohyu, 53.8mg% in Kiyooka daidai and 49.9mg% in Tokosu.

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