When pH of egg yolk solution was adjusted from 2 to 12 by 0.1N HCl or 0.1N NaOH, the maximum amounts of precipitate and highest turbidity was obtained at pH 5.5. Higher value of viscosity of the pH-adjusted egg yolk was obtained in the region below pH 4 and above 10. The maximum amount of precipitate and highest turbidity was obtained at pH 7 in LDL (Low Density Lipoprotein) solution and at pH 4.5 to pH 5 in Livetin solution. However, these phenomena were not related to changes of viscosity. HDL (High Density Lipoprotein) showed high turbidity below pH 4 or above pH 11 in 5% NaCl solution, and about 90% HDL was precipitated below pH 4. Disc electrophoresis of egg yolk showed that bands with Rf of 0.2 or less decreased below pH 5. These bands were main components of HDL. From above findings, the changes of viscosity of egg yolk was estimated to be mainly due to the properties of HDL.

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"Sordum" plums harvested in Yamanashi Prefecture in 1976 were stored for 15 days at various temperatures (3°C, 10°C, 20°C and 30°C). The deterioration of the plums proceeded with the rise of storage temperature in the range of 3°C to 20°C. However, when stored at 30°C, their physical and chemical changes were simillar to those observed during storage at 3°C. Physiological disorder was slightly observed in the pulp of the plums during storage at 30°C. From these results, high-temperature storage (30°C)seemed to keep the qualities of plums for a certain period.

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In the previous paper, the biomass production of Saccharomyces cerevisiae FRI-44 cultured on acetate as a sole carbon source was reported. In this paper, fermenting activity and the quality of the acetate grown yeast were examined with the object of testing its aptitude as baker's yeast. Fermenting activity for sponge-dough and sweet-dough as well as the durability of the yeast was almost equal to that of commercial baker's yeast. Maltose adaptabilty of the yeast was markedly inferior to commercial yeast. The decline of the adaptability of the yeast must be caused by acetate cultivation, because when S. cerevisiae FRI-44 was cultured on molasses, its adaptability and maltose fermenting activity were superior to commercial yeast. Although fermenting activity of the acetate-grown yeast in Meissel solution was also inferior to commercial yeast, the activity was considerably restored by adding a wheat flour extract, "koji" extract or yeast extract. The volume and quality, especially odor, of a bread loaf baked by using the acetate-grown yeast were not so good as that baked by using commercial yeast. The storage carbohydrate content in the yeast was lower than that in commercial yeast. The content of free amino acids in the yeast was lower than that in S. cerevisiae FRI-44 cultured on glucose as a carbon source.

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A new method for measuring salt and acetic acid content in mayonnaise was proposed, which is based on conductivity measurement in both water-ethanol and water-pyridine solvent systems. Between the specific conductance for a 300 times diluted solution of mayonnaise in the water-ethanol (67 vol%) solvent system and the salt content, a highly precise regression curve was obtained without the influence of coexistent acetic acid. The salt content estimated from regression curve agreed with that obtained from argentometry with an error of 0.02%. In the water-pyridine (10 vol%) solvent system, the found specific conductance of the 300 times diluted solution of mayonnaise agreed with the calculated value, i.e. the sum of the specific conductances which were determined separately in standard salt and acetic acid solutions. The acetic acid content can be calculated from the estimated salt content in the water-ethanol solvent system and the specific conductance of the 300 times diluted solution of mayonnaise measured in the water-pyridine solvent system by use of the two equations set up between the concentrations and the specific coductances of salt and acetic acid in the water-pyridine solvent system. The acetic acid content calculated by this method agreed with that obtained from alkalimetry with an error of 0.01%.

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To make clear the aroma property and to develop the aroma preservation method of early spring green tea (Shin-cha), the change in its aroma components during storage was investigated by GC-MS and sensory test. The aroma had n-nonylaldehyde and cis-3-hexenylhexanoate for its main ingredients and they decreased remarkably during the storage of tea. According to sensory test, cis-3-hexenylhexanoate seemed to contribute to the typical aroma of early pring green tea. Propionaldehyde, 1-penten-3-ol, cis-2-penten-1-ol and 2, 4-heptadienal, were not detected in early spring green tea but produced during the storage of tea. The aroma of early spring green tea was perfectly preserved only by low temperature storage at -70°C in comporison with the cold storage at 5°C or nitrogen gas packaging at room temperature.

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The mung bean was immersed in water, homogenized and extracted with water several times. By this extraction, 74% of total N(TN) was re- covered. Furthermore, by subsequent extraction with 0.2% NaOH, 13% of TN was recovered. 92% of water-extracted nitrogen was proteinous nitrogen, 84% of which was precipitated at pH 4.5. Mung bean protein roughly resembled soybean in its amino acid composition and disc-gel-electrophoretic pattern. 78% of TN in the sprout was extracted by homogenizing with water, but its disc-gel-electrophoretic pattern indicated decreased molecular size. From the water-extract of mung bean, about 60% of starch could be presumably recovered. Some properties of this starch were as follows; moisture 11.13%, ash 0.04%. whiteness 83, and gelatinization temperature 62.1°C.

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The flow behavior of 5wt% rice starch pasetes was measured at 20-80°C by using a capillary tube viscometer. The flow equation was expressed as follow:
γ=(1/K)(g_cτ-g_cτ_y)ⁿ
where, γ: shear rate (sec^-1), τ: shear stress (g_f/cm²), g_c: gravitational conversion factor(g·cm/g_f·sec²). The flow parameters K, n and τy were calculated using a non-linear least square method.
The value of τ_y could be overlooked, and the value of n was 1.2. The values of K which fixed n=1.2 and τ_y=0.0 were expressed by following ANDRADE equation.
K=5.41×10^-4exp(5.34×10³/R_gT)
where, T: measuring temperature (°K), Rg: gas constant(cal/g-mol·°K).

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