The analysis of factors affecting the syneresis of konjac mannan (KM) gel was carried out, and an empirical equation was obtained for predicting the degree of syneresis during storage. SEIKO (konjac flour containing ca. 90% of KM) was used as a raw material. The syneresis of KM gel proceeded with the elapse of storage period until the equilibrium was established after 20-30 days. The degree of syneresis, which was defined as the percentage of weight loss of KM gel after 30-day storage, decreased almost linearly with the increase in the concentration of KM and in the pH value of the gelling mixture. With the rise in gelation temperature and the depression in storage temperature, the degree of syneresis fell in a similar manner. The commercial grade of SEIKO (evaluated by the rheological properties of KM sol), partial substitution of KM with another polysaccharide, and the swelling time of SEIKO had little or no influence on syneresis. On the basis of these findings, an equation to estimate the degree of syneresis at equilibrium was given as follows:
Y=-3.0C-0.22T-4.9P+0.17t+89.5
where Y is the degree of syneresis (%), C the concentration of SEIKO (%), T the gelation temperature (°C), P the pH value of gelling mixture, and t the storage temperature (°C). It was confirmed by appling this equation to KONNYAKU (a commercial product) that the equation is available for the prediction of the degree of syneresis of KM gel.

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Volatile aromatic components obtained from semi-fermented tea (Pouchung and Oolong tea) were analyzed by the GC-MS method, As its main aroma components, terpene alcohols and their oxids, benzyl alcohol, phenylethanol and indole were identified. A total amount of these aroma components contained in high quality tea was larger than that in low grade tea. Most of the aroma components in semi fermented tea were produced during the manufacturing process. They were mostly originated from the non-volatile components by enzymatic breakdown during fermentation process. The compositions of the aroma components in made teas were different among varieties. It was suggested that genetic characteristics of each variety were probably related to the composition of aroma components.

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In previous papers, we have studied the cooking-rate equaitons of root vegitable slices, and thermal diffusivity of spherical ones. In this paper, we studied the cooking-rate equation including the thermal property of a spherical potato. The values of thenmal diffusivity and Arrhenius parameters were calculated by using a non-linear least squares method. The cooking-rate equations were obtained as follows:
dx/dθ=k_{n, β}(1-x)(x+0.1)
_{kn, β}=1.26×10¹⁷exp(-2.94×10⁴/R_g(t+273.2))
∂t/∂θ=0.111(∂∂²t/∂rr²+(2/r)∂t/∂r)
where, x(-): cooking ratio, θ(min): cooking time, t(°C): cooking temperature, r(cm): radius, R_g=1.987cal/g-mol·°K: gas-constant. The value of thermal diffusivity obtained was higher than 0.097cmcm²/min obtained in the previous paper.

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The flow equation of sugar, salt and sugar-salt-skim milk solutions was expressed as follows;
γ=(1/K)g_cτ, K=A exp(B/(t+273.2))
where, γ(sec^-1); shear rate, τ(g_f/cmcm²); shear stress, g_c (g·cm/gf·secsec²); gravitational conversion factor, K(g/cm·sec); viscosity, and t(°C); temperature. The values of A and B were expressed as a function of concentration S(wt%).
For sugar solution (S=0-30wt%, t=10-50°C);
A=10^{(-1.17×10-2S0.98-4.98)}, B=10.7S^1.14+2.02×10⁸
For Salt solution (S=0-24wt%, t=10-50°C);
A=10^{(3.05×10-3S1.89-4.88)}, B=1.95×10³
The value of K for sugar-salt-skim milk solution (S=0-15wt%, t=10-50°C) was expressed as follws;
K=(k_Sx_S+k_Nx_N+k_Mx_M)(1-4.2×10^-3x_Sx_N-3.4×10^-3x_Sx_M-8.4×10^-3x_Nx_M+1.67×10^-2x_Sx_Nx_M)+3.8×10^-3x_Sx_N+2.7×10^-3x_Sx_M+7.1×10^-3x_Nx_M-1.26×10^-2x_Sx_Nx_M
where, k_S, k_N, k_M (g/cm·sec); K's values of sugar, salt and skim milk solutions for concentration of S, andx_S, x_N, x_M (-); mass fractions of sugar, salt and skim milk.

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The effect of rice added to soybean on the quality was studied by using 4 types of low salt soybean-miso: miso of soybean-koji only (control, II), miso of koji prepared by mixing cooked soybean and rice (III), miso of the mixture of soybean-koji and rice-koji (IV), and miso of the mixture of soybean-koji and cooked rice. (1) In miso using rice with soybean (III-V), sugar, contents, Y% in color and aroma components were increased in comparison with miso using soybean only (II). The formers were also highly evaluated than the latter by the sensory test. (2) Depending on the way to employ rice, some differences were observed in enzymatic activities and color of miso. That is, III had the highest protease activity and IV, V showed higher Y% value in color. (3) No remarkable differences were observed in the enzymatic activities remained in miso except for protease, and microflora during ripening among II-V.

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The characteristics of the components were investigated during ripening of low salt tamari (0-9%) prepared by adding ethyl alcohol (2-8% V/W). (1) The pH value and total sugar content were reduced, whereas acidity was increased with decreasing salt concentration to less than 4.5% level. The quality of low salt tamari containing less than 4.5% salt was different remarkably from that of conventional tamari. (2) Solublization and hydrolysis of soybean protein were promoted and free amino acids in tamari were increased by decreasing salt concentration. (3) The formation of color in tamari was not affected by salt concentration, but by ethyl alcohol which showed a tendency to promote the browing slightly. (4) Low salt tamari of less than 4.5% salt contained considerably rich ethyl acetate flavour resulting in lower organoleptic evaluation. However, addition of ethyl alcohol to a conventional tamari in 2% concentration or to low salt tamari containing salt more than 9% was effective to improve the flavour and also, effective to make low salt tamari. (5) From the results mentioned above, 9% salt, as a minimum limit concentration might be suitable for making low salt tamari.

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Eight kinds of tamari were prepared by changing the combination ratis of salt in 18-9% range and ethyl alcohol in 0-5% range, in order to study the most favorable combination of salt and ethyl alcohol for making low salt tamari. (1) Common components in six kinds of low salt tamari made in the combination of salt in 15-9% range and ethyl alcohol in 2-5% range were basically similar to those of conventional tamari containing 18% salt, although some difference was observed in pH, acidity, sugar content and thedegree of hydrolysis of protein. (2) Conventional tamari not containing ethyl alcohol had a poor flavour and a higher acid value. On the other hand, conventional and low salt tamari made by adding ethyl alcohol had a rich flavour, such as acetaldehyde, ethyl acetate and others, and also provided lower acid value with increasing concentration of the ethyl alcohol. (3) Low salt tamari containing more than 15% salt was excellent in flavour, particularly conventional tamari made by adding 2% ethyl alcohol and 18% salt had the most favorable flavour to indicate the effect of the ethyl alcohol addition for the flavour improvement.

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Acid-sensitive fractions (ASFs) were prepared from defatted meals by two procedures. ASF I was prepared by precipitation at pH 4.5 and removal of 1M NaCl-soluble materials from the precipitate. ASF II was prepared by precipitation with 1M NaCl at pH 4.5. ASF I always gave the higher yield than ASF II. ASF I seems to contain ASF II in its inner part. Some factors, wich influence on the formation of ASFs, were investigated. The sorts of acid, the addition procedure of the presence of phytate and the concentration of proteins did not have any effect on the yields of ASF I and II. However, some interactions between lipids and proteins were suggested, because further removal of lipids from defatted meals gave the lower yield of ASFs. Solubilities of ASF II in the presence of salts, ethylenediamine tetraacetic and reducing or oxidizing reagents indicated the little possibility of electrostatic, chelating or disulfide bonds. Its good solubility in sodium dodecyl sulfate and urea solutions suggested that hydrophobic interactions were predominant in ASFs.

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