The browning reaction products prepared by heating a mixture of D-xylose (2M) and glycine (2M) at 100°C for 2 hr. were fractionated into melanoidins and low molecular reductones by gelfiltration with Sephadex G15. Strong antioxidative activities were found in the melanoidin fractions. When these fractions were refractionated by G50, antioxidative activities were distributed in a wide molecular range of melanoidins. From the results of the paper partition chromatography and the antioxidative activities of these melanoidins, relatively low molecular melanoidin was used to further fractionation by gel filtration with G100. When the antioxidative activity of each fraction was compared at same color leve1, its activity was found to be distributed to all over the colored fractions. The melanoidin fraction by G100, Which exhibited a strong antioxidative activity, was further separated into three bands by thin Iayer chromatOgraphy with cellulose powder. Each band was named as melanoidin A, B and C. Of those three melanoidins, melanoidin B was considered to be pure on paper electrophoretical and ultracentrifugal patterns. The melecular weight of melanoidin B was about 4500. In comparison of antioxidative activities of those three melanoidins, C showed the weaker inhibitory effect on oxidation of linoleic acid than A and B which exhibited almost the same antioxidative activity each other.

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The pH range for the growth of Sacch. rouxii in the environment of a high concentration of sodium chloride was studied and its utility for Miso brewing was also shown in respect to the pH dependence.
1. The strains of Sacch. rouxii were classified into three groups on the basis of their pH dependence in the saline medium at 25°C.
Group-A: Growth was almost equal in the range of pH3.5-6.5 in the media of 0-3M of NaCl.
Group-B: Normal growth was limited in the range of pH 3.5-6.0, 3.5-5.5 in the media of 2M, 3M of NaCl, respectively.
Group-C: Normal growth was limited in the range of pH 4.0-5.0 in the media of 3M of NaCl.
In general, the range of growth pH was reduced at higher concentrations of sodium chloride and at higher temperature. This tendency was most remarkable in the Group-C.
2. In the distribution study, it was revealed that Group-A was most abundant in salty-redMiso of excellent quality and Group-C was the commonest in Soy-mashes.
3. By means of plating on three different pH (4.8, 5.5 and 6.0) media containing casamino acid, yeast extract and 18% sodium chloride with McIlvaine's buffer solution, group enumeration was successfully distinguished.
4. From the results of brewing trials, Group-A was considered to be the most effective yeast for Miso fermentation.

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Arachin was purified by gel filtration chromatography on a Sephadex G-200 column and by ion exchange chromatography on a DEAE-Sephadex A-50 column in 0.076M tris-citrate buffer with 0.01M 2-mercaptoethanol (pH 8.6). The molecular dimension and the subunit structure were investigated.
The axial ratio of the monomer form (9.2S, M.W. 180, 000 by sedimentation-diffusion method) was estimated to be 3.5 from the frictional ratio f/f0=1.288 and 4.6 from the intrinsic viscosity [η]=0.060dl/g assuming the molecule of a prolate ellipsoid of revolution with 30% hydration, and of the dimer form (14.7S, 350, 000) 3.0 from f/f_J=1.252 and 3.2 from [η]=0.044 dl/g.
It was considered from the results of ultracentrifuge, gel electrophoresis and N-terminal amino acid analysis that arachin was consisted of six kinds of main subunits having the average molecular weight of 29, 000, which possessed three glycines, two (iso-) leucines, and one valine as the N-terminal amino acid.

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It was shown that the distinction between astringent and non-astringent varieties of kaki resulted partly from the difference of alcoholdehydrogenase activity which might possibly related with the formation of acetaldehyde in the flesh of kaki fruits. But, the varietal difference of the enzyme activity was not studied definitely. Then, the alcoholdehydrogenase activities of astringent and non-astringent kaki fruits were detected by using Thumberg method. In the non-astringent variety, it was found clearly that the alcoholdehydrogenase in the flesh of fruits was very active. In the astringent variety, the enzyme activity was not able to detect because of the inhibition by soluble kaki tannin. But after the removal of soluble tannin in the components of Thumberg tube, such as precipitation with gelatin, the enzyme activity was found slightly. And after the artificial removal of astringency by the treatment of ethanol, very active alcoholdehydrogenase was detected in the flesh of astringent fruits as same as non-astringent one. The results suggested that the alcoholdehydrogenase might be active to the full extent in the astringent kaki fruits, and so the distinction between astringent and non-astringent varieties might be not explained sufficiently by the varietal difference of alcoholdehydrogenase activity.

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Employing 23 varieties of kaki, 8 of non-astringent variety, 11 of astringent variety and 4 of variant variety, the varietal differences of changes of acetaldehyde contents, ethanol contents and alcoholdehydrogenase activities in the flesh of kaki fruits, followed with the removal of astringency, were studied. The acetaldehyde contents of non-astringent fruits were nearly ten times as much as astringent one. In the astringent varieties, the acetaldehyde contents increased suddenly to the similar extent of non-astringent one in the course of the artificial removal of astringency by the treatment of ethanol or carbon dioxide, in proportion to the ethanol contents of the flesh of fruits. Alcoholdehydrogenase activities were almost not different between astringent and nonastringent varieties, and also not accompanied with either the acetaldehyde contents or the ethanol contents of the flesh of fruits. The acetaldehyde contents of astringent varieties after the artificial removal of astringency by the treatment of carbon dioxide were much as compared with the artificial removal of astringency by the treatment of ethanol. On the basis of these results, some mechanism of the acetaldehyde formation in the flesh of kaki fruits were discussed.

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It was found that the curing of farm products meant a little surface drying operation in constant rate period.
The design formulae which determine the flow rate, the humidity and the temperature of the air were derived by solving the drying equations to satisfy the conditions that the drying was carried out at a given time in accordance with a given average drying ratio within a given range of uneven drying ratio in the facility from the assumption of constant adiabatic saturation temperature of the drying air through the packed products. The formulae are as follows:
Y_L≤α/β
Q=S·γ·K·L/Y_L
HW-H=β/{(K·T/W₀)·(1-exp(-Y_L))/YL)}
where Y_L=dimensionless height(-), α=limit of unevenness(-)
β=directing dried ratio(-), Q=flow rate of air (m³/hr),
S=cross-sectional area of bed (mm2), γ=specific volume of air (m3/kg), K=mass transfer coefficient (kg/m₃·hr·ΔH),
H_W=saturate absolute humidity at wet bulb temperature (kg/kg'),
H=absolute humidity (kg/kg'), T=drying period (hr), W0=observed specific weight of products in bed (kg/m³)
The basic data of Satsuma orange (Citrus unshiu Marc.) are arranged, and an example of design calculation is given for an actual facility.

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Establishment of the determination method of lactic acid and lactate in milk was investigated. A colorimetric method derived from Davidson was pursued. This method involves the precipitation of fat, protein and lactose by the combined action of copper sulfate and calcium hydroxide, oxidation of the lactic acid into acetaldehyde by sulfuric acid in the presence of copper sulfate and a colorimetric determination using p-hydroxydiphenyl. Oxidation and colorimetric procedures were studied on the following items: concentration and quantity of p-hydroxydiphenyl solution to be added, stability of color developed as well as the maximal absorbance wavelength of the color developed. From experiment it revealed that the omission of the addition of copper sulfate to the sulfuric acid resulted in a decrease of the optical density of about 50%. So far as the clarification procedure was concerned, the addition of 25% copper sulfate was simplified to a single successive addition with calcium hydroxide without warming. No significant difference was observed compared with control carried out by the Davidson method.
This method can be applied for the detection of neutralizers. It is also available for the grading of condensed milk and milk powder.

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