Lysinoalanine(LAL)contents of Pidans on the market and hen or quail Pidans made in our laboratory were determined by an amino acids analyser. LAL was recognised in white and in yolk of each Pidan with ranges of 2.8 to 9.3 and 2.9 to 8.7mM per 100g of protein, respectively. The formation of LAL was investigated by model experiment using the hen's egg white as a protein source. When diluted egg white was heated in boiling water for 30min., LAL was formed even at natural pH values of stored egg white and even at pH8. The formation of LAL was dependent on the pH, temperature and time of treatments. Longer time, higher pH and temperature caused more formation of LAL. The degradation of cystine was more drastic and more rapid than the formation of LAL. Among some reagents examined, sodium carbonate was only one which played specific role on the formation of LAL.

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Soybean milk was coagulated by lactic fermentation using Streptococcus thermophilus(T), Streptococcus lactis(L)or a mixture of T and L without addition of calcium as a coagulant. The curds obtained were ripened by Penicillium caseicolum. As a result of rising the acidity at early stage of the ripening, pH of curds could nearly maintain 6.5 after 2 week's ripening. Increase of water soluble nitrogen after 1 week's ripening was so rapid that 3 week's ripening rate reached more than 80%. The contents of total free amino acids in TL sample increased in 1150mg/100g after 3 week's ripening. Amino acids liberated comparatively high amounts were glutamic acid, aspartic acid, lysine and so on. To prevent rapid progress of the ripening during the short term, the curd was coated with parafin after eliminating mold from surface, and then ripened at lower temperature(5°C). This treatment was effective to control the ripening. Trypsin inhibitor(TI)activity did not change during the ripening and it was found that most of TI activity was originated from whey remaining in curds.

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1. General constituents in the juices and purees, pectins in the purees, sugars, organic acids and metals in the juices from six varieties of plums(Plunus salicina)harvested in Yamanashi Prefecture were determined to elucidate their general properties and characteristics.
2. The juices(purees)contained 1.11-1.88%(1.11-1.91%)of titratable acidity, 2.61-4.71%(2.70-6.19%)of total sugar, 2.46-4.59%(2.61-2.03%)of reducing sugar, 0.163-0.281%(0.188-0.281%)of ash, 0.347-0.765%(0.317-0.726%)of ether extracts, 0.045-0.106%(0.055-0.147%)of total nitrogen and 0.012-0.027%(0.011-0.027%)of free-amino nitrogen.
3. Pectin contents in the purees were 0.054-0.375% and the coefficient of correlation of pectin and waterinsoluble solid contents showed high value(r=0.999). The juices contained only glucose and fructose as a major monosaccharide showing that the ratio of glucose/fructose were 1.02-1.91. Malic acid was the main acid of the plum juices and they also contained a small amounts of Quinic acid. The juices were very rich in K(695.3-1157.8ppm), rich in Mg(38.7-66.6ppm)and Ca(24.0-44.2ppm), and poor in Fe, Cu and Mn.

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The synergistic effects of gelatin on the viscous properties of polysaccharide C-8(D-mannose: D-galactose:D-glucose:D-glucuronic acid:pyruvic acid=1:1:1:3:1)were investigated. The flow curves of a mixed solution of the polysaccharide C-8 and 0.5% gelatin showed a yield point, and approximated to plastic flow. Dynamic modulus of the mixed solution reached to maximum value at a concentration of 0.1% polysaccharide C-8 in 0.5% gelatin solution, while dynamic viscosity increased in proportion to polysaccharide concentration. At pH5.4, dynamic viscoelasticity of the mixed solutions showed the highest value than the other pH values. Value of tan δ of the mixed solutions showed the lowest value at a concentration of 0.1% polysaccharide C-8 in 0.5% gelatin solution.

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Stimulative effect of fermentation for acetic acid bacterium No.2 strain(accepted from National Institute of Fermentation Technology, Chiba)was observed when a sake cake was supplemented in 0.5% concentration to the basal medium. Effective substances in sake cake were soluble in water, methanol and pyridine and were not adsorbed on various adsorbents such as active carbon, active alumina and silica gel. By the fractionation on the multi-column of Amberlite IR-120(H⁺)and Amberlite IR-410(OH^-), effective substances were separated into neutral fraction and acidic fraction. Neutral fraction which was not adsorbed on both resins exhibited highly stimulative efiect, whereas acidic fraction which adsorbed on Amberlite IR-410(OH^-)was slightly stimulative. From the results of further purification by gel-filtration on Sephadex G-15 and column chromatography on LC-R-3 ion exchange resin, it was considered that main effective substance in neutral fraction was composed of low molecular sugars and other unknown substance.

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(1) Neutral fraction in sake cake which was separated on multi-column of Amberlite IR-120(H⁺)and Ambereite IRA-410(OH^-)had superior effect for stimulation of acetic acid fermentation.
(2) Effective substance in neutral fraction was further separated by column chromatogrophy of active carbon-celite, celite and Sephadex G-15 etc., and was isolated by purification on paper chromatography with several solvents.
(3) The isolated material was homogeneous as judged by paper chromatography, and agreed closely with authentic glycerol on Rf value.
(4) The isolated substance which was acetylated with pyridine and acetic acid anhydride system was identical with that of authentic glycerol, on gas chromatography, infrared spectrum and NMR spectrum analysis.
(5) The isolated substance added in 10mg% to the basal medium showed the remarkable stimulative activity on production of acetic acid, and also reduced the lag time on growth of acetic acid bacterium No.2 strain. These stimulative activities by the isolated substance were no difference to those of authentic glycerol.
(6) From the above results, it can be concluded that the main substance in sake cake to stimulate acetic acid fermentation is a glycerol.

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The effect of high concentration of sugar alcohols on a simple enzymatic microassay procedure of D-fructose was described. The enzyme is the crystalline stalline D-mannitol dehydrogenase obtained from Leuconostoc mesenteroides. D-Fructose could be recovered without any interference in the presence of large excess amount over 5000-fold range of xylitol and maltitol. Sorbitol did not show any appreciable interference up to 500-fold excess amount. This enzymatic procedure was confirmed again to be applicable for the microassay of D-fructose in the samples containing high concentration of sugar alcohols used as sweet additives.

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