Ann is a Japanese traditional cake base made from red bean or other similar legumes by the process consisting of soaking in water, cooking, grinding, removing hulls and washing with water. It is a mass of separated cells(ann particle)of cooked beans. Starch granules inred bean ann are swollen but not solubilized. The starch granules separated carefully from ann could be almost completely hydrolyzed by gluco-amylase, as already reported by the authors. However, in this research, it has been revealed that the starch granules separated from ann could be only partly hydrolyzed by β-amylase-pullulanase, whereas the previously separated starch from bean, being gelatinized in hot water, is almost completely hydrolyzed. The β-amylase-pullulanase method proposed by K. KAINUMA was confirmed to be more sensitive to detect small changes in the degree of gelatinization as well as retrogradation of starch. It was also found that during storage at 5°C for several days the ann and gelatinized bean starch showed for its retrogradation more apparent decreases in the degree of hydrolysis by β-amylase-pullulanase comparing by gluco-amylase.

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This study was conducted in order to define the characteristics of infrared and near infrared spectra of dried laver (Porphyra yezoensis) so that near infrared diffuse reflectance method might be applied for a nondestructive analysis of chemical composition. By comparing the infrared spectra measured by KBr-pellet and that by ATR methods, near infrared spectra in 1.1 to 2.5μm region were assigned in conjection with a substance related to the quality. (1) Infrared spectra consisting of the major 6 absorption bands were assigned to Amide I, Amide II and Amide III, and fundamental vibration of C-H and C-O groups. (2) Near infrared spectra consisting of about 35 absorption bands were also assigned to various overtone and combination vibrations of C-H, N-H, O-H or C=O groups. (3) Both the infrared and near infrared spectra showed a general tendency that the better the grade of the quality was, the more a content of protein was, and by contrariesthe less a content of carbohydrate was. (4) An organic solvent- or water- extractability of substance related to near infrared bands was assigned qualitatively measuring organic solvent- or water- extracted laver samples, respectively. (5) The effect of moisture content of the sample on near infraed spectrum showed in some wavelength regions in addition to absorption bands related to water itself. This effect is independent upon the grade of the quality and the change of spectrum is reversible to moisture content.

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Effect of sodium chloride(NaCl)on the gel formation of soybean protein to which powdered palm oil was added has been investigated. Hardness of the gels decreased remarkably with the increase of NaCl content, but palm oil powder depressed the decrease. Larger the oil content, higher water holding capacity(WHC)was, but the change in WHC of the gels containing various amounts of NaCl was different depending on the oil content. The viscosity of each soybean milk was incresed by heating at 50°C and after a period reached to a maximum and then decreased, although the maximum viscosity and the time reached to the maximum was different depending on NaCl and oil contents. For the milk to which relatively small amount of oil(5%)was added, the time to reach the maximum viscosity was shortest in the samplle containing 0.25% NaCl. The experiment on nitrogen solubility index for the protein of soybean milk without addition of the palm oil revealed that the protein solubility was markedly influenced by NaCl content and heating period.

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The sucrose content of irradiated chestnuts was determined during storage at various temperatures. The sucrose content was enhanced by cold-storage or gamma-irradiation. Sucrose was accumulated in irradiated chestnuts and a preferable dose range for the accumulation of sucrose was between 0.5 and 1 kGy. Storage temperature had a profound effect on the sucrose content and the degree of the sucrose accumulation increased with the decrease of storage temperature in both unirradiated and irradiated samples. The spoilage of chestnuts was dependent upon storage temperature irrespective of irradiation treatment.

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An enzymatically modified protein was applied to bread making as an improving agent. Baking quality was valued through loaf volume, grain size of clumb and rate of the hardening during storage. Addition of modified gelatin which contained L-leucine dodecyl ester covalently to bread resulted in excellent effects, but gelatin, the mixture of gelatin hydrolysate and L-leucine dodecyl ester, and L-leucine dodecyl ester did not have any effect. The measurement of unfrozen water by a pulsed NMR spectrometer suggested that more water in the bread with the enzymatically modified protein was kept in the loosely bound state than in the bread without the surfactant over a long period of storage.

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The effect of NaCl on relative viscosity of the pectin solution prepared from radish root pectin was studied. The results obtained were as follows: (1) Viscosity of the pectin solution was increased but its pH was decreased with the addition of NaCl. (2) The increase in viscosity of the pectin solution by added NaCl was proportional to the decrease in pH of the solution. (3) It was presumed that the addition of NaCl into the pectin solution caused the ion-exchange of H-ion of carboxyl group in pectin with Na-ion to form HCl which, by ionizing, decreased the pH of the pectin solution. (4) The inversely proportional change of viscosity to the pH change of the pectin solution was confirmed by measuring viscosity and pH of the solution which was diolyzed after the addition of NaCl to remove HCl produced, as well as of the solutions which containaed different amount of pectin with or without NaCl.

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Production of ethyl ester mixture from butter fat by C. cylindracea lipase was investigated in order to use as flavorant. It was observed that C. cylindracea lipase effectively converted the free fatty acids released from butter fat by lipase to ethyl esters in the presence of ethanol. Esterification reaction was followed by the titration of fatty acids and gaschromatographic analysis of ethyl esters. The optimum ethanol concentration for effective ester production was in the range of 10-12%. Final products were obtained as the mixtures of fatty acids and ethyl esters. Ethyl ester formation by C. cylindracea lipase was performed also from unhydrolyzed butter fat in the presenceof ethanol. In this case final products were also obtained as the mixtures of fatty acids and ethylesters. The rates of the esterification reaction at 14°C and 26°C were approximately the same. Ethyl ester profiles in various stages of esterification reaction showed that C₄, C₁₀ fatty acids were esterified more rapidly than others, and the esterification rates of C₆, C₁₄ fatty acids were relatively slow. This tendency was about the same for both hydrolyzed and unhydrolyzed substrates. Through this investigation, a production method of ethyl ester mixture from butter by C. cylindracea lipase was established and this product was ascertained to be able to be widely used as a flavor material.

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The effect of added CaCl₂ on relative viscosity of the radish root pectin-NaCl solution and its reaction mechanism were investigated. The results obtained were as follows: (1) Viscosity of thepectin-NaCl solution gradually increased along with an increase of the amount of added CaCl₂. (2) Carboxyl groups of pectin in the NaCl solution were found to react with NaCl to form Na-salt, and also the other elements, Ca, Mg and K, originally combined with carboxyl groups were exchanged with Na to some extent. (3) The Na bound to carboxyl groups of pectin in the NaCl solution was found to be exchanged with Ca by adding CaCl₂ to the solution, causing an increase of viscosity of the solution. It was assumed that CaCl₂ added to the radish root pectin-NaCl solution lead to the ion exchange of Na of carboxyl groups of pectin with Ca, which might introduce much cross-linkageswithin pectin molecules, and increased viscosity of the pectin-NaCl solution as well as crisp palatability of salted radish root products as reported in the previous paper.

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The application of frozen pork plasma to processed meat products was attempted as a part of the investigation on the effective utilization of animal blood. In the first place, changes in quality of the frozen plasma during storage was checked, and then processed meat products such as Bologna sausage and smoked pork loin which contained the plasma were manufactured and evaluated for their quality and acceptability. No changes in quality of the plasma were observed during storage up to 15 weeks at -25°C. Flavors of Bologna sausage and smoked pork loin were markedly improved by the replacement of 60% and 30%, respectively, of iced water with the plasma. Additional favorable effects were noticed in the color of products, i.e., the replacement enhanced raddish tint and retarded a little its fading. This is probably due to remaining red blood cells in the plasma. No other changes in quality and acceptability of the products were found.

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