Scald treatment by submerging potatoes in hot calcium chloride solution was applied for peeling of sweetpotatoes and taroes, and it was demonstrated that this treatment was effective in terms of peeling yeild and qualities. In the case of sweetpotatoes, adequate scalding condition was in the range of temperature, 130-140°C, and time, 2.5-3min. for submerging in CaCl₂ solution. The peeling loss was only about 8.5%. The peeled product had a good appearance and color, and discoloration of that was less than product peeled by alkaline solution. The peeling efficiency was influenced by the variety, the season of harvest and the storage period. In the case of taroes, an adequate scalding condition was to submerge in CaCl₂ solution at 120-130°C for 2-3min. and peeling loss was about 12%.

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Effect of the concentration of acid and sugar on the consumer preference for beverages containing 10, 30, 50% apple juice, and also effect of the concentration of apple juice on the taste of beverages were examined by means of organoleptic test. (1)For the beverages containing 30% apple juice, the bevearge containing 0.45% acid were preferred significantly, at 5% significant level, rather than that containing 0.25% acid, but there was no significant difference in the preference for beverages having different acid concentrations when the beverages contained 10 or 50% apple juice. Beverages with a brix of 13.0 to 12.0 tendened to be preferred when the beverages contained 10, 30, or 50% juice. (2)Acid taste of the beverages increased in proportion to the acid concentration, it was also affected by the amount of sugar added; acid taste was lowered with the addition of sugar. Sweetness was also lowered with increasing acid concentration, but its effect was not so much as that of sugar on the acid taste. (3)The balance between acid taste and sweetness tended to coincide with overall impression. This correlation was examined by comparing the sugar to acid ratio; there was no particular sugar to acid ratio always preferred, but the content of sugar was a more decisive factor in determining preference. (4) Beverages containing 50 or 30% apple juice were preferred more than those containing 10 or 100% apple juice, with the difference being statistically significant.

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A study of rheological properties of konjac flour sols was made for various concentrations and at different swelling temperatures in order to establish the standard condition for the optimum swelling of konjac flour sol in the process of making konjac. Texture was evaluated for the konjac gels at the time when the sols reached maximum viscosity. The viscosity of konjac flour sol and the texture of konjac gel, prepared from 3.33, 1.67 and 1.25% sol, and swollen at 40, 60, 80 and 90°C, were measured. The viscosity and the texture were measured with a coaxial-cylinder rotational viscometer and a rheolometer, respectively. Konjac flour sol showed pseudoplasticity with yield value, and for the samples of higher concentrations the characteristics of elastic fluid were observed. The higher the konjac flour concentration was, the smaller the temperature dependence of the sol viscosity was. The exponent n, which indicates shear-rate dependence of the viscosity, became smaller as the temperature dropped and the concentration increased. The hardness of konjac gels prepared at maximum viscosity gave almost constant values in spite of different conditions for preparation. The gel hardness had a close linear correlation with the maximum viscosity of sol. The elastic recovery of the gel was dependent on its concentration: the higher its concentration was, the stronger its recovery.

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Viscoelastic behaviour and spinnabilities of low concentration soy protein dope(10-14%)were investigated in order to understand the spinning mechanism. A 14% dope with pH8.6 showed spinnability(20m/min). The results suggested that colloidal corpuscles of protein could be oriented into thread-form materials like connected beads when the dope was passed throughout the spinning nozzle. Viscoelastic behaviour of the dope largely changed around pH11. In proportion to alkali treatment, the viscoelastic value of the dope increased slowly and frequence of G' for the dope reduced gradually up to pH11. But, on the contrary, the viscoelastic of the dope decreased and frequency dependenc of G' for the dope increased when pH was higher than 11. It was found that the mentioned pattern of alkali denaturation was not depended upon the soy protein concentration, but viscoelasticities of the dope were influenced by the protein concentration. When ι-carrageenan was added into the dope that could not be spun, the dope was changed into good spinnable one and the fiber of excellent quality was produced.

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In order to estimate the effect of gas atmosphere on the shelf-life of beef, as the first step, beef steaks were packaged in deep draw tray systems which were injected with O₂, CO₂ and their mixtures: (a)O₂=3, (b)O₂/CO₂=2/1, (c)O₂/CO₂=1/2, (d)CO₂=3. For these steaks, sensory evaluations, analyses of metmyoglobin, bacterial counts, pH, and volatile basic nitrogen were carried out. The sensory evaluation for color indicates that the higher the concentration of O₂, the brighter the redness of meat color. But, as for steaks stored in O₂=3, the surface discoloration was faster than the ones in the other atmospheres, and the significantly higher bacterial counts might be responsible for this discoloration. In the high CO₂-containing atmospheres, though the steaks had slightly acidic odor at first(2 day), they were comparatively in good quality in the final stage. The bacteriostatic effect of CO₂ was similarly recognized between 33-100%. The steaks showed the longest shelf-life as a consumer-pack, when they were stored in O₂/CO₂=2/1 gas atmosphere.

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Viscosities of mayonnaise, tomato ketchup, sauce and miso were measured in a considerably wide range of shear rate(2-1×10⁵ sec^-1)by using a capilary flow viscometer. It was found that these food materials showed the OSTWALD flow behavior. The flow curves of these materials could be well fitted to CROSS' flow equation.

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It was reported in a previous paper that the soluble proteins of soybean miso (mame miso)were derived from soybean koji. In the present paper the relation of soluble proteins between rice miso and rice koji was immunobiochemically studied. The results obtained are as follows: (1)Five protein components were detected in the soluble protein fraction of rice miso and found to be the antigens common with the soluble proteins of rice koji. (2)It was also found by the use of rice koji anti-serum that seven protein components were the common antigens between rice koji and soybean koji at the beginning of fermentation.

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It was reported in a previous paper that the soluble protein components of rice miso were derived from rice koji. In the present paper the change of proteins during maturing process of miso and their enzymatic activities were investigated. The results obtained are as follows: (1)Five soluble protein components of rice miso were found to be the antigens common with the proteins of spores of rice koji starter by investigating the sequence of protein fraction in the maturing process of miso(2)An acid sugar-protein of rice miso having an estimated molecular weight of 53000 daltons showed an amyloclastic activity almost up to the end of maturing. (3)An acid sugar-protein of koji having an estimated molecular weight of 25100 daltons showed a proteolytic activity.

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Microstructure of soybean protein gel containing palm oil was analyzed by electron spin resonance by using nitroxide free radicals, TEMPO and TEMPOL, as spin probes. The determination of isotropic hyperfine coupling constant values indicates that this gel has a regular structure consisting of hydrophilic and hydrophobic circumstances. Correlation time analysis showed that microviscosity of aqueous phase increased with an increase of the added oil amount. This tendency is very similar to that of the increase of hardness of the gel with increasing oil content. These results suggest that spin probe method is useful to study the microstructure and hardness of soybean protein-oil-water gel.

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The impedance ratio of a potato tuber at 50kHz to 5kHz(Z_50k/Z_5k)was dependent upon the irradiation dose, while it was independent of the localitywhere potatoes were grown. It remained constant during the storage after irradiation. The impedanceratio for unirradiated potatoes was almost the same irrespective of the potato variety. The possibilities of differentiation between unirradiated and irradiated potatoes and estimation of irradiation dosewere discussed based on the results.

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