Deboned chicken meat paste (DCMP) has been used as a material for making sausage to date. The gel-formation ability of DCMP, however, greatly varies among the commercial products depending on their manufacturers. In order to investigatethepropertiesofDCMP, the moisturecontent, percentage of proteins and lipids, and pH value were examined. The effects of heating temperature and time on the gel-formation of DCMP were also investigated. (1) Among the five kinds of DCMP, large differences in several components, particularly the protein and lipid contents, were recognized. (2) The gel-formation ability of DCMP was proportional to the amount of salt soluble protein. DCMP which contained a large amount of salt soluble protein was able to form a strong gel. The heating-gel of DCMP showed the highest jelly strength at around 60°C. (3) Analysis of the heating-gel by SDS-PAGE revealed that the myosin heavy chain (MHC) exhibited characteristic behavior. That is, it did not change until at 40°C, but then decreased at 50°C and then a little increased at 60°C when compared to that of 50°C. Particularly at 60°C, a cross-linking reaction of MHC was observed.

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The most important factor in keeping quality of minimally processed vegetables is to keep the product at low temperature immediately after processing. In this report, we studied on the cooling methods of shredded cabbage in terms of cooling rate of the products which were packed in various kinds of packaging practices, as well as changes of product's temperature after packaging. As a result of modeling of unsteady state of heat conduction in the cooling process of the packaged products, it became possible to simulate a temperature profile of the product. It is necessary to reduce the packaging size less than 7.0cm in diameter of spherical shape of packaging style and less than 5.7cm in thickness of brick shape of packaging style provided the product is desired to be cooled from 25 to 5°C within 30 minutes by chilled water. Vacuum cooling was a very efficient method of cooling the shredded vegetables. Cooling from 20 to 5°C was able to be conducted within 15 minutes. Neither temperature distribution in the product's temperature nor tissue damage of the product was observed. It was practical to use a polystyrene foam box with ice to maintain the temperature of the product packaged in a plastic film below 5°C for l2 hours under 30°C of ambient condition. It was necessary for the product packaged in the polystyrene foam box to be contacted with ice to prevent the deterioration caused by temperature increase during distribution process.

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Extraction of piperine and volatile compounds from black pepper was carried out with liquid carbon dioxide (L-CO₂) at the pressure of 70-200kg/cmcm² and 20°C, and then the effect of ethanol as an entrainer was investigated. Volatile compounds were extracted with small amount of L-CO₂, and recovery was about the same as the case of using supercritical carbon dioxide (SC-CO₂) at 300kg/cm² and 40°C. With an increase of the ethanol concentration (0.5-2.0 w/w%), the recovery ratio of piperine with L-CO₂ increased, and the amount of CO₂ used in order to obtain the same recovery ratio of piperine decreased. The amount of CO₂ used and the recovery ratio of piperine with SC-CO₂ was the same as the case of extraction with L-CO₂.

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The presents study was aimed at developing a psychrotrophic starter culture to manufacture fermented meat products. A psychrotrophic lactic acid bacteria isolated from beefs was identified as Lactobacillus species, and designated as Lactobacillus sp. SK-1001. Lactobacillus sp. SK-1001 showed favorable properties for the meat starter culture, such as rapid growth, rapid pH decrease of a sausage, and inhibition of undesirable bacteria in laboratory scale manufacturing of at 5°C and 10°C. The antibacterial substances produced by Lactobacillus sp. SK-1001 seemed to be lactic acid and a slight amount of acetic acid. It was considered that the combination of Lactobacillus sp. SK-1001 and incubation at 5 and/or 10°C was appropriate to manufacture the safe meat products, such as fermented sausages and fermented hams.

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Plastic films, mainly containing epoxy-acryl resin, coated and baked on aluminum foil, were individually immersed in a lemon-flavored aqueous solution in sealed glass jars. Each solution was pasteurized and stored at 25°C for two weeks. Then the films were immersed in diethyl ether for one day to extract flavor components sorbed in the films. The components were quantitatively analyzed by GC-MS. As a result, the amount of ethyl acrylate in the coating resin is well correlated with the total of sorption ratio of flavor components.

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The chemical forms of aluminum in tea infusions of Sencha (Japanese green tea), Hojicha (roasted green tea), black tea, oolong tea and pu erh tea were analyzed based on the 27A1-NMR spectra. It was suggested that they were mainly a complex of one mole of aluminum and three moles of oxalate and a complex of aluminum, oxalate and fluoride.

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Natto is a non-salted fermented soybean food in Japan. Some Bacillus subtilis strains (formerly called "B. natto") are utilized for producing natto. In natto production the bacteria growing on steamed soybeans hydrolyze soybean proteins to peptides and amino acids and synthesize viscous material (r-polyglutamate) which is characteristic of natto. To produce natto with strong umami-taste, B. subtilis strains with high activity of protease were screened from soil, harvested rice plant and so on. A strain NN-1 was selected out of 295 strains tested, because of its high activity of protease in the growing broth (121 U/ml) and ability of producing natto both with strong umami-taste and large amount of viscous material. In the presence of phytone, the liquid culture of strain NN-1 was more viscous than that of a commercial strain. Strain NN-1 also produced more γ-glutamyltranspeptidase (1060international unit/l), which was thought to be a key enzyme in γ-polyglutamate synthesis. StrainNN-1 was identified as B.subtilis. The natto produced by strain NN-1 contained about twice free amino acids of the natto produced by a commercial strain and showed higher scores in sensory evaluation.

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Quality of the juice made from apple fruit that had fallen during a typhoon was compared with the juice of fully matured fruit picked from the tree by comparing the amounts of volatile compounds. In the case of the cultivar'Jonathan', which ripens in mid-season, there were few differences in juice quality between juices made from fallen and fully matured one. It was considered that this cultivar was almost entering the maturation stage when typhoon damage occurred. However, in the case of late ripening cultivar'Fuji', the juice quality had many disadvantages in fallen fruit juice compared with full ripe fruit juice. Some precipitation was observed in the fallen fruit juice. The fallen fruit needed many days to reach the fully matured stage when typhoon damage occurred. Forty-four volatile compounds (including 4 unknown compounds and one overlapping peak of two compounds) were detected by GC methods with these two different kinds of raw materials. In the cultivar 'Jonathan', there were few differences between total amounts of volatile compounds of juice made from fallen fruit and that of fruit juice and their organoleptic evaluations of aroma were also the same. On the other hand, the total amounts of volatile compounds in fallen fruit juice of'Fuji'were less than a quarter of fully matured fruit. The fallen fruit juice had the lesser fruity aroma and considerably green aroma. From the above results, fallen fruits during full maturing stage could be used for natural juice-making. However, the immature fallen fruit that required many days as 'Fuji'could not be used for natural juice until reaching the fully matured stage. It could be better to use such immature fallen fruit for clarified juice or blending with other juices.

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Inhibitory effects of a calcium preparation on the growth of food-borne bacteria and yeast were investigated, and its application to food was advanced. The calcium preparation was made from oyster shells, and then treated electrically with ohmic heating. This product has been already used as a nutrient supplement. Chemical analysis showed that this preparation contained mainly calcium and other minor elements. The minimum inhibitory concentration (MIC) to bacterial growth was measured. This preparation and its major component Ca(OH)₂ showed almost the same MICs in the range of 0.07 to 0.1%. Both Gram-positive and negative bacteria were inhibited at the same concen- trations. In the case of NaOH or KOH, MICs ranged from 0.09 to 0.15% or from 0.15 to 0.24%, respectively. Yeasts were inhibited at the lower concentrations than bacteria. Viable cell number in food decreased or did not increased by addition of the calcium preparation. Bacillus, Escherichia, Salmonella and Staphylococcus inoculated to food were suppressed their growth by the calcium preparation. The calcium preparation was more effective than Ca(OH)₂ to get the same effects. It was shown that the calcium preparation used as a nutritional additive could be applied to control the microorganisms in food. Also, the possibility of utilizing the alkaline range to keep the quality of food was suggested.

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Traditional tofu is rarely used in frozen processed foods because its texture becomes sponge-like after freezing. Also, most available freeze-dried tofu lacks the desirable smooth and soft texture of traditional tofu. By using new ingredients and preparation methods with curdlan, thermogellabie β-1, 3-glucan produced by bacteria, practical preparation methods of freezable processed tofu and freeze-dried tofu were studied. Freezable processed tofu was prepared using an optimal formula of curdlan 1.2% and waxy corn starch 3% with a new preparation method. This freezable processed tofu was used in frozen foods such as Mabo-dofu (a Chinese dish of soybean curd with spicy minced meat), Agedashi dofu (deep-fried tofu in stock) and Miso soup, resulted in the smooth and soft texture like Kinugoshi tofu. Freeze-dried tofu was also prepared by an optimal formula of curdlan 0.5%, waxy corn starch 1% and a controlled freezing condition. The resulting tofu had a smooth and soft texture after reconstitution with hot water.

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To study the difference of taste characteristics of soy sauce and soy paste between Korea and Japan, organic acids, free sugars(FS), free amino acids (FAAS) and oligopeptides (OPT) were analyzed, and their contents were compared. Furthermore, the difference of the palate between Japanese and Korean people was discussed according to the results obtained. The results were as follows: (1) The soy sauce of Japan (SSJ) was lower in pH, smaller in the NaCl content and larger in the contents of total nitrogen and FS than the soy sauce eaten commonly in Korea (SSK). (2) The SSJ contained large amounts of organic acids, especially lactic acid and pyroglutamic acid, whereas the SSK contained mostly lactic acid. (3) The FAAS content in SSJ was nearly 3.7 fold than that of SSK, the major acids found being glutamic acid, aspartic acid and proline in SSJ, and glutamic acid in SSK. (4) The OPT in SSK was about 2.8 fold than that of SSJ. The OPT in SSK was mainly composed of glutamic acid, aspartic acid and proline, but that of SSJ was mainly composed of proline and aspartic acid. In addition, the amount of OPT in SSK was similar to FAAS content, but the OPT in SSJ was about 10% the amount of FAAS content. (5) The soy paste of Japan (SPJ) was lower in pH and remarkably larger in the content of FS than the soy paste commonly eaten in Korea (SPK). (6) The content of organic acids in SPJ and SPK was almost the same, the major ones being pyroglutamic acid, citric acid and lactic acid in SPJ, and lactic acid and pyroglutamic acid in SPK. (7) The FAAS of soy pastes made in both countries were hardly different in content, the major ones being glutamic acid, leucine and aspartic acid in SPJ, and glutamic acid and leucine in SPK. (8) The OPT of soy pastes in both countries were almost the same content, and the main component amino acids were almost the same variety. Furthermore, OPT contents were only 49% the amount of FAAS content in both. The results described above seem to indicate that the taste of soy sauce is strongly affected by FAAS, especially glutamic acid in the Japanese product, and both glutamic acid and OPT in the Korean product. The similarity in content of FAAS and OPT in soy pastes may account for the similarity in taste between the Korean and Japanese products, although the Japanese soy paste seems to be a little sweeter. From these results, it is presumed that Japanese people especially prefer the flavor enhancer of glutamic acid, whereas Korean people prefer both the tastes of glutamic acid and OPT.

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