Stabilization of soybean proteins with sucrose, glycerol and ethylene glycol was studied. At low ionic strength (μ=0.1), their stabilizing effect on inhibiting the aggregation of water extracted protein at various pH was slight, but, at high ionic strength (μ=0.5), it was recognized clearly in order of sucrose glycerol ethylene glycol as 20% (v/v) of addition, respectively. Addition of 20% sucrose was effective on inhibiting the aggregation of the protein near its isoelectric point by heating (80°C for 30min).
Also, addition of 20% sucrose inhibited the dissociation of the 11S component to 7S at alkaline pH, but didn't inhibit the dissociation to 3S at acidic pH and had stabilizing effect to prevent the polymerization of the 3S. By measuring differential ultraviolet spectrum of the 11S component, it was shown that the sucrose inhibited the conformational change of the tertiary structure at acidic pH.

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Saturated fatty acid monoglycerides were added to edible solid fats in concentration from 0.5 to 5% and allowed to stand at 30°C. Open-capillary melting point, solid fat index, differential scanning calorimetry, transition of polymorphism were determined and crystal growth was observed by an electron microscope. The crystal growth of hardend soybean oil and palm kernel oil was slightly accelerated by the addition of saturated fatty acid monoglycerids, however, such tendency was not observed in beef tallow or hardend whale oil. The melting point of all the samples was lowered with increasing the added monoglycerides in amount.

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The effect of unsaturated fatty acid monoglyceride and propylene glycol ester of fatty acids on the growth of the crystals in edible solid fats was determined.
The results obtained were as follows:
(1) The crystal growth in hardened soybean oil and palm kernel oil was inhibited by the addition of propylene glycol ester, however, such effect was not observed when beef tallow and hardened whale oils were used as sample oil.
(2) In the case of hardened vegetable oil, the crystal growth was accelerated by unsaturated fatty acid monoglyceride, but the open capillary melting point could not be measured because the measured values were scattered and the values became markedly low during standing.

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The effect of lipophilic sugar fatty acid esters on the growth of crystal in edible solid fats was investigated. Addition of sugar ester to hardened soybean oil and hardened palm kernel oil clearly inhibited crystal growth. Inhibition of crystal growth was also found by electron microscopy in the case of beef tallow and hardened whale oil. However, addition of 3% or more of the sugar ester to solid fats became stiff during standing, with sudden rise in open capillary melting point, the values of which did not correspond to other measured values.

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The cooking quality of spaghetti was evaluated by using a texturometer, and changes in texture of spaghetti during packaging, sterilizing and storing were investigated.
Clear texturometer curves for cooked spaghetti were obtained, but no adhesiveness sign appeared in the curves. Both values of hardness and gumminess of spaghetti decreased hyperbolically with cooking time. Slope and y-segment of the line obtained in the logarithmic coordinate plots of the values of hardness and gumminess against the cooking time, might be useful indexes for evaluation of the cooking quality of spaghetti. Values of cohesiveness was almost constant over various cooking time.
Values of the three parameters of packaged and sterilized samples were almost same as or greater than those of samples that were cooked for same time as packaged ones. The tendency of the changes in these values with cooking time were the same as that of the samples which were only cooked. A stabler spaghetti texture was obtained when sterilized for shorter time at higher temperature.
Optimum cooking and sterilizing condition can be determined by measureing these texture parameters.

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