Tea leaves were stored for 10-21 days at 5 or 10°C in the atmosphere of various kinds of N₂, O₂ and CO₂ concentrations; control (air, i.e., N₂, 80%; O₂, 20%), experiment A (N₂, 85%; O₂, 10%; CO₂, 5%), experiment B (N₂, 90%; O₂, 5%; CO₂, 5%) and experiment C (N₂, 93%; O₂, 2%; CO₂, 5%). Concentrations of N₂, O₂, CO₂ and ethylene in the storage vessel were measured by gas chromatography during the storage.
1) The quantities of the both O₂ uptake and CO₂ output by respiration of tea leaves were in the order of control, experiment A, experiment B and experiment C during the storage.
2) Ethylene production per day from storaged leaves was measured after the storage of 8 days. As ethylene was produced in the order of control, experiment A, experiment B and experiment C, it was considered that the ethylene production was affected by O₂ concentration in the strage atmosphere.
3) The contents of tannin and caffeine were not so much changed during the storage, whereas that of total ascorbic acid was remarkably decreased, especially in the form of reduced ascorbic acid. And it was clear that the decrease of ascorbic acid was affected by O₂ concentration. The contents of amino acids such as glutamic acid, aspartic acid, glutamine, asparagine and theanine were changed during the storage but an uniform tendancy was not found.

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The protein, carbohydrate and ash contents of soybean seeds of 11 varieties in U.S.A. and 23 samples in China were determined. Soybean seeds were sieved to obtain of 3 sizes, i.e. size 1 (large), size 2 (medium) and size 3 (small). Compared with U.S.A. variety, Chinese sample was high in carbohydrate content and low in ash content. However U.S.A. variety showed about the same protein content as Chinese sample. The size 3, as compared with the size 1, was low in the protein content and high in the carbohydrate content. On the other hand, the ash content was not changed evidently. From the results of analysis of variance, the protein, carbohydrate and ash contents were significantly influenced by the variety in U.S.A. and Chinese sample, and the protein and carbohydrate contents were further influenced by the size of seed in Chinese sample. On the correlation between chemical component pairs, the protein content was negatively correlated with the oil content in U.S.A. variety, and was also negatively correlated with the carbohydrate content in Chinese sample. The oil content was negatively correlated with the carbohydrate content in Chinese sample.

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Amylomaize VII, amylomaize V, normal corn, waxy corn and potato starches were irradiated with ⁶⁰Co-gamma rays at the dose levels from 2×10⁴ to 100×10⁴ rad to determine the changes in physicochemical properties by irradiation.
Irradiated starches were characterized by determination of amylography, specific viscosity, blue value, pH, acidity, carbonyl content, reducing value and limit of β-amylolysis.
Irradiated starches showed a decrease in viscosity and blue value, and an increase in reducing value with increasing dose levels. These results were seemed to indicate the degradation of starch molecule. A slight oxidation of starch was suggested by a decrease in pH and an increase in acidity and carbonyl content.
Amylomaize VII and amylomaize V starches were less sensitive than the other starches in terms of irradiation effects. The rheological properties determined by amylography and Ostwald viscometer changed at the lowest dose(5×10⁴ rad)and the other properties changed above 20×10⁴rad.
The limits of β-amylase hydrolysis of normal corn, waxy corn and potato starches increased slightly by irradiation(100×10⁴ rad). On the other hand, β-amylolysis limits of amylomaize VII and amylomaize V starches were lower about 5.5% and 2.5% respectively than that of non-irradiated samples. The decrease of β-amylolysis imit enlarged with increasing amylose contelnt.

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Employing Citrus unshiu, Citrus natsudaidai and Citrus kabos, essential oils wererecovered from the waste fluid extruded from an In-Line juice extractor.
Such physical and chemical properties as specific gravity, refractive index, specific rotation, acid value and aldehyde content of each essential oil were examined. Gas chromatography was conducted to separate aromatic constituents. The major components of each essential oil were D-limonene, γ-terpiene, myrcene and α-pinene. As aroma components 25 compounds were found in Citrus unshiu oil, 27 in Citrus natsudaidai oil and 27 in Citrus kabos oil.

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Using proteins isolated from soybean meal, the effect of partial hydrolysis of proteins on their emulsifying properties was studied, and the following results were obtained:
1) Hydrolysates having a slightly bitter taste were produced by hydrolyzing the proteins with a low concentration of a protease (0.05% vs. substrates). The emulsion stability of these hydrolysates at pH 4.5 was superior to that of unhydrolyzed soybean proteins at pH 7.
2) Hydrolysates having hardly any bitter taste were obtained by hydrolyzing the proteins with 0.05 N hydrochloric acid for a period of 5-48 hours at 95°C. The emulsifying capacity and emulsion stability of these hydrolysates at pH 4.5 were both much superior to those of unhydrolyzed proteins at pH 7.
3) When the concentration of enzyme vs. substrates was around 0.3% or the concentration of hydrochloric acid was 2-3 N, the values of the emulsifying properties of the hydrolysates varied randomly, and the reproducibility of the values was very low.
4) The fact that partial hydrolysis by dilute hydrochloric acid generates hardly any bitter taste and exhibits a remarkable effect upon the emulsifying properties of soybean proteins, especially in a slightly acidic and neutral range, suggests that the utilization of these hydrolyzed proteins as an emulsifier in food processing is feasible.

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To evaluate the emulsifying properties of single-cell proteins from the standpoint of food uses, the emulsifying capacity(EC)and emulsion stability(ES)of the proteins extracted from yeast of the Candida family grown on n-paraffin were determined, and the following results were obtained:
1) The EC and ES of the proteins in a water extract of yeast were hardly affected by pH, concentration of sodium chloride and heat treatment of the extract.
2) The EC and ES of the proteins precipitated from unheated alkaline extract decreased slightly in the isoelectric region(around pH 4.5). The EC decreased and the ES increased respectively with the increase of protein concentration.
3) The behavior of the ES and EC of the heated alkaline extract was similar to that of the supernatant obtained by precipitating proteins from the extract, and they showed maximum values in the isoelectric region. On the contrary, the EC and ES of the acid precipitated proteins exhibited minimum values in the same isoelectric region.
4) The fact that the emulsifying properties of the yeast proteins were superior to those ofsoybean proteins, and exhibited higher values in a slightly acidic to neutral pH range, seemed toexhibit possibilities as an excellent emulsifier in food processing.

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Fundamental gelatinization properties of wheat flour by an extruder were studied. Results are as follows.
(1) Weak flour began to flow at the temperature of 120°C, was gelatinized above 138°C, was texturized above 170°C and had the softest texture above 190°C under the compression of 150kg/cmcm². These behavior were observed more evidently under the compression of 200kg/cmcm².
(2) In the case of strong flour, expansion ratio was smaller than that of the other, and had no maximum value below 200°C.
(3) Expansion ratio was closely related to apparent viscosity, and their relationships were formulated as follows.
(Weak flour)
(Strong flour)

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