Supernatant of coagulated soymilk on Tofu processing have been termed Yu in Japanese, and have been main waste water of Tofu factory. The recovery of protein from the waste Yu water is expected to be effective for reduction of waste water facilities and the recovered proteins should be utilized as food materials. However, the Yu fraction was suggested to contain some factors which effect on the growth of rats, since the protein efficiency was negative. Inactivation of trypsin inhibitors by heating did not affect on the nitrogen balance and protein efficiency ratio of Yu fraction; PER, NPU, BV and D of perfectly and partially inactivated Yu were -0.83, 64.8, 68.8 and 94.3 and -2.74, 73.8, 78.3 and 94.2, respectively. Addition of Yu fraction increased PER of casein; PERs of casein diets at 0, 3, 7 and 10% addition of Yu fraction were 1.83, 2.11, 2.60 and 2.52, respectively. The supplement of Yu fraction on the diet caused apparent poor protein quality; the order of supplyment effect were Fu>Tofu>casein>egg.

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The quantitative differences in non-volatile flavor components such as free amino acids and their related compounds, nucleotides, organic acids and peptides among dorsal, abdominal and red meat parts of Katsuobushi were analyzed by high performance liquid chromatography (HPLC).
The amounts of major free amino acids and their related compounds such as histidine, carnosine and anserine differed too greatly among these parts, whereas those of other minor amino acids were nearly the same. The amounts of the major three components in the abdominal part and the red meat part were about four-fifths and a half of those in the dorsal part, respectively. The amounts of the major nucleotides such as IMP and AMP and organic acids such as lactic and acetic acids in the red meat part were smaller than those in the dorsal and abdominal parts. Peptide fraction from each part of Katsuobushi was fractionated by HPLC. As a result, we supposed the presence of some peptides other than anserine and carnosine.

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In the previous papers, we reported the spinnability of dispersions of chicken muscle and carp muscle proteins, by the addition of a free fatty acid or an anionic surfactant and that the shear stress of these protein dispersions was increased in such cases. In the present study, we investigated the effect of oleic acid (OA), anionic surfactants such as sodium dodecylbenzene sulfonate (SDbS) and nonionic surfactants such as polyglycerine monooleate on the loss modulus (G″) and storage modulus (G′) of 10% carp and chicken muscle protein dispersions, at 30-60°C, as measured by Reolograph Sol. Milk casein dispersion at 20% protein concentration and pH 8 which shows excellent spinnability even in the absence of OA or SDbS, was used as a basis of reference. The chicken and carp muscle protein dispersions which showed spinnability exhibited G″/G′ ratio of 0.35 or more, while those showing no spinnability, either containing nonionic surfactant or no additives or else at inappropriate pH or temperature, exhibited G″/G′ ratios of less than 0.20. The G″/G′ ratio of the milk casein dispersion, containing no additives, was more than 0.80. The results showed a clear correlation between the G″/G′ ratio and the spinnability of protein dispersions.

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In order to make clear the mechanism of the formation of Ann granules from legumes, the separation of cotyledon cells of Adzuki bean (Vigna angularis) without gelatinizing starches in the cells has been examined. It was found that the separation of single cells was attained by the successive treatments with acid and alkali as follows. Dry beans were first immersed in 0.1M hydrochloric acid for 48 hours at 25°C, where the pH value of the immersed solution was about 1.5. The beans were then washed with water, dehulled, separated into two cotyledons, and washed again with water. The cotyledons were finally stirred in 0.06M sodium hydroxide solution for 1hour at room temperature by a magnetic stirrer, where the pH value of the immersed solution was about 12. The treatment with alkali resulted in the separation of cotyledon cells. Starch granules in the cells thus obtained showed typical birefringence under a polarizing microscope. The separation procedure presented here was successfully applied to several varieties of Adzuki beans and kidney beans (Phaseolus vulgaris), though the separating condition for the latter was somewhat different from that for the former.

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The correlation among activity of enzymes, qualities and sensory evaluation was investigated for 19 samples of Natto. Values of variation coefficient among the samples were 33.8% for protease activity (PA), 25.9% for stringiness of viscous substance (SV), 22.6% for γ-glutamyltranspeptidase activity (GA), 20.6% for hydrolysis ratio of protein (HP) and 7.8% for solubilization of protein (SP), respectively. There was a correlation significant at 1% level between PA and SP, however there was no significant correlation between PA and HP. There was correlations significant at 1% level betwen PA and sensory evaluation (SE), and SP and SE, and at 5% level between GA and SE, and SV and SE. The coefficients of determination to sensory evaluation were 0.794 for PA, 0.464 for SP, 0.058 for HP, 0.278 for SV and 0.237 for GA, respectively. Therefore, the sensory evaluation had a tendency to be high when PA and SP increased or when both GA and SV increased.

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Powdered ginger is usually added to fish sausage or the like as a spice. If the ginger proteinase retains its activity in the powder, the addition of the powder to salted fish meat paste may affect on gel strength of the heated product. Therefore, we ascertained the existence of the proteinase activity in the power and whether the addition of the powder causes textural deterioration of the product. Non-sterilized (a), ethylene oxide gas-sterilized (b) and heat-sterilized (at 155°C for 5s) (c) powders of sun-dried ginger made in India were used as the samples. Kamaboko was prepared using frozen surimi of Alaska pollack. The casein and myofibrillar proteins (Mf-p) hydrolyzing activity was observed in a and b, but not in c. In a-and b-containing kamaboko, both gel strength and folding test value were clearly low in comparison with those of control Kamaboko. Moreover, the hydrolysis of Mf-p was observed in SDS-polyacrylamide gel electrophoretic patterns. On the other hand, the addition of c caused neither the decrease of the gel strength of kamaboko nor the hydrolysis of Mf-p. These results show that the addition of powdered ginger to the salted fish meat paste, by the sort and the amount, causes the textural deterioration of the heated product by the action of the ginger proteinase.

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In the previous papers, we reported the spinnability of dispersions of chicken muscle and carp muscle proteins by the addition of a free fatty acid or an anionic surfactant.
In the present study, we investigated the effect of oleic acid (OA), anionic surfactant sodium dodecylbenzene sulfonate (SDbS) and nonionic surfactant polyglycerine monooleate (PMO) on the shear stress of carp and chicken muscle protein dispersions, as measured by Haake Rotovisco RV-12 at 40°C. A protein concentration was fixed at 5% throughout the study.
The shear stress of protein dispersions was increased by the addition of OA or SDbS at 15% per protein at pH 12, but was apparently uneffected by the presence of PMO, which has no effect on spinnability of animal protein dispersion.

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The present study aims at a good grasp of penetration of infrared radiation energy into a sweet potato exposed to far infrared radiation. The transient temperatures and the distribution of the temperature in the sweet potato heated by a far infrared heater were measured by the CA-thermocouples. By using the experimental results and thermal diffusivity of a sweet potato, it was found that there was no effect of radiation on the heat transfer in the domain deeper than 2mm under the surface. But, we could not get a conclusion about the penetration by this method, bcause it was impossible to measure precisely the temperature close to the surface. Then, on two type models of the sweet potato composed of dried sweet potato material, water and void, the apparent absorption coefficients in the infrared region were determined from those of the materials and water. The damping curves of infrared radiation energy in the sweet potatoes were estimated from the apparent absorption coefficients. From he curves, we could conclude that the distance, which infrared radiation energy absorbed by a sweet potato was damped to 1% of the initial value, was 0.10-0.22mm under the surface.

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The effects of xylose and glucose on deterioration of δ-tocopherol (Toc) containing cookies were investigated. The stability was evaluated by the changes of peroxide value (PV) of the lipid fraction after baking and storage at 40°C. PV of the cookies blended with xylose remained low after baking and storage for 6 months. On the other hand, PV of the cookies blended with glucose remained low after baking but rapidly rose after 2 months storage. The addition of δ-Toc was effective for prevention of deterioration in the cookies blended with xylose, but not glucose. These results suggested the synergistic effect of xylose and δ-Toc, but not glucose and δ-Toc. Twenty % of δ-Toc in the cookies were decomposed during the baking process, regardless of amount of blended xylose or glucose. On the other hand, the loss of δ-Toc during the storage was slightly inhibited by xylose and not by glucose.

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The clarification of an aqueous extract from dried leaves of Stevia rebaudiana Bertoni was investigated by using magnesia adsorbent, The most suitable magnesia adsorbent was made by calcining magnesium hydroxide at 450°C for 30 minutes. The best result was obtained when using the same weight of adsorbent as that of the solid content in the aqueous extract and stirring vigorously for 60 minutes at 40°C. By this procedure, the coloring substances were removed very effectively and the recoveries of the two major Stevia sweeteners, stevioside and rebaudioside-A, were 95% and 96%, respectively. The filterability of the adsorbent-treated solution was also excellent. The adsorbent was re-usable after burning at about 450°C for 30 minutes. When the adsorbent-treated solution was further treated with strongly acidic and weakly basic ion exchange resins, a much purer extract was obtained. This purified solution contained the Stevia sweeteners and some saccharides present in the original extract solution but no soluble silica or proteins.

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Frost damage of Citrus fruits is giving an unfavorable impact on their growers. An emergence of bitterness in Citrus Iyo fruit by frost damage was investigated through the differential determination of limonin and limonoate A-ring lactone in the fruit.
The rate constant for the formation of limonin was 0.149h^-1 in the juice at 21°C. The activation energy of the reaction was found to be 53.6kJ mol^-1. The segments of Citrus Iyo fruit injured by frost, in 2 or 3 days after being thawed, became bitter proportionally to the degree of frost damage.
The limonin content of the injured fruit was highly correlaed to the intensity of bitterness in a sensory evaluation test.
Critical conditions of refrigeration which induce bitterness of Citrus Iyo fruit were presumed to be between 4 and 6 hours duration at -7°C.
When cut Citrus Iyo fruit was frozen at-30°C and then stored for 4 months at -20°C, some tasted strongly bitter and the highest limonin content among them reached to 28.4ppm.

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This paper describes the changes in phosphorylase and invertase activities during ripening of bananas subjected to ethanol and ethylene treatments.
Starch content in the banana pulp decreased from about 20% at the green stage to less than 1% at the fully ripe stage while total sugar increased to 20%. At the same stage of ripeness, the starch and sugar contents, and enzyme ativities of ethanol- and ethylenetreated fruits were comparable to that of the control.
Phosphorylase activity increased during the period of rapid starch breakdown(peel color index 2) and declined at the later stages of ripening, concurrent to the decrease in starch content. On the other hand, invertase activity was very low at the green stage but increased sharply at peel color index 3 (more green than yellow)concomitant to the increase in sucrose.

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