K-value and deterioration conditions of total lipids (AV, POV and TBAV) were measured together with fatty acid composition and fatty acid content, as well as further sensory tests, in order to find out the lowering of freshness under low preservation temperature (+5°C) with the passage of time in dorsal ordinary meat of the following seven species of fish; red barracuda, Sphyraena japonicus Cuvier, mackerel, Scomber japonicus, frigate mackerel, Auxis tapeinosoma, puffer, Lagocephalus lunaris, horse mackerel, Trachurus japonicus, common japanese conger eel, Astroconger myriaster and gurnard, Chelidonichthys kumu. (1) Horse mackerel and common japanese conger eel, on the 5th day of preservation, had low K-values (lower than 20%) and AV, POV and TBAV, thereby, from the results of the sensory tests as well, these fish were found edible raw (as "Sashimi"). (2) K-values of red barracuda, mackerel, frigate mackerel, puffer and gurnard, increased up to around 20% on the 3rd day, however their AV, POV and TBAV increased very little. The sensory tests also revealed that these fish were found edible raw (as "Sashimi"). However, on the 5th day, their K value increased up to 40% and their AV, POV TBAV increased slightly, . but they were found edible if cooked, except frigate mackerel which was found to be at the first rotten stage judging from the K-Value (up to 54%), and AV, POV, TBAV and sensory tests. (3) The differences in fatty acid composition and fatty acid content were observed among the types of fish, however, their changes with time were not observed so much.

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Though maturation is one of the most influential steps to quality in processing of noodles, no established mechanism of maturation has ever been reported. In this repect, the microstructural and rheological changes of maturated chinese noodles were studied by using scanning electron microscopy and the Do-Corder, respectively. Two different methods for maturation, viz., maturation at the step of sheets and the one at the step of strips were compared. Maturation always promoted producing inner vacuoles in the structure of cooked noodles, but the size of them produced in the cooked noodles after maturation at the step of sheets were larger than those produced after the one at the step of strips. The Do-Corder curve of maturated noodles showed two peaks (at 75 and 85°C) and was similar to the curve for an oxidiaed dough.

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Aroma concentrates were obtained from distillates of Matsutake harvested in Japan and Korea. Aroma concentrate was analyzed by combined gas chromatography and mass spectrometry. The yield of flavor concentrate from Japanese Matsutake was 146ppm and that of Korean was 80ppm. Major components were 1-octen-3-ol, cis-2-octenol and methyl cinnamate. Flavor compositions of both were similar except the content of methyl cinnamate. Although the amount of flavor concentrate from Korean Matsutake decreased to 44ppm after the storage of 66 hours under room temperature, no decrease was observed on the amount of flavor concentrate obtained from another Korean Matsutake which had been kept in cold storage for 66 hours. The flavor composition changed extremely by the storage under room temperature, on the other hand, slight change was found in cold storage.

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Tofuyo is a traditional food in Okinawa, and is made from soybean curd with koji, salt and awamori (distilled liquor). It was suggested that the texture of soybean curd affects the quality of Tofuyo. Optimum conditions, therefore, for preparation of the curd were investigated. It was found that chemical properties of coagulant and its concentration, and the pressure under which coagulated soy-milk was pressed for solidification affected the quality of soybean curd. The best conditions were as follows; the final concentration of calcium sulfate: 20mM, final pressure: 38g/cmcm². The curd was characterized as follows; hardness: 10-11×10⁴dyne/cmcm², moisture: about 76%, and texture: suitable elasticity and fine texture. Tofuyo prepared with dehydrated curd by enforced drying, e.g., by warm wind, in oven or under vacuum, was not good for taste. The best quality of Tofuyo was obtained with the curd (hardness: 20-30×104dyne/cmcm²) which was gradually dehydrated at room temperature (25°C), and a hardness of the product was 14-18dyne/cmcm².

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Sugar component of raw persimmon (18 cultivars) and dried persimmon (7 cultivars) were investigated by both gas chromatography and thin-layer chromatography. Especially, the difference of sugar contents of astringent fruit (beforc and after the processing of removal of astringency) was examined. Free sugars contained in both the sweet and astringent persimmon were revealed to be mainly fructose, glucose and sucrose. The content of sucrose in flesh of persimmon was influenced by the cultivar, harvesting time and the method of removing astringency. It is noteworthy that sucrose content of astringent persimmon was negligible in mature, over-mature and dried fruits respectively. The ratios of fructose to glucose in persimmon are shown in the following results; raw flesh of fruits (1.0: 1.3-1.4), over-mattlre flesh of fruits (1.0:1.2), dried fruit flesh (1.0:1.3-1.4), and white powder deposited on the surface of dried persimmon (1.0:4.3). The white powder obtained carefully from the surface of dried persimmon was almost found to be glucose in crystal form.

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Changes in the content of pectic substances, ascorbic aid and polyphenols, and the activity of pectinesterase in kiwi fruit (Actinidia chinensis Planch. cvs. Hayward, Bruno, Monty and Abbott), were investigated during growth and ripening after harvest. The following results were obtained: (1) Total pectin content in the fruit reached 3.0-3.5% at four months after pollination. It decreased with further growth, and the ripened fruit contained only 0.7%. HCl-soluble pectin accounted for 80-90% of the total pectin in the growing fruit, while water-soluble pectin accounted for approximately 50% of the total pectin in the ripened fruit. (2) The highest activity of pectinesterase was observed on the final sampling day (Nov. 9), but no activity was detected in the ripened fruit. (3) The total ascorbic acid content decreased with fruit enlargement, and was 90-110mg/100g in the ripened fruit. (4) The total polyphenol content was 180-220mg/100g in the fruit at one month after pollination, and decreased with growth of the fruit. A further decrease was, however, not seen during ripening. The changes of the cholorogenic acid, flavanol-tannin and leucoanthocyan contents during growth were similar to those in the total polyphenol content. The leucoanthocyan in kiwi fruit consisted of leucocyanidin and leucodelphinidin in a ratio of nearly 1:3.

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Rheological properties of 15% w/w poly (vinyl alcohol) (PVA)-5% w/w gelatin mixed gels (frozen at -20°C, and melten at 15°C every 24h) were examined by the measurement of longitudinal vibration. The freezing time was chosen as 24, 48, 72, and 96h. The degree of polymerization and the degree of saponification of PVA was about 2400 and 99.6±0.3mol%, respectively. The molecular weight and the isoionic point of gelatin was 5×104 and 5.4, respectively. The dynamic Young's modulus, E' and mechanical loss tangent, tan δ were obtained at 2.5Hz by longitudinal vibrations of a cylindrical gel. The E' increased with increasing number of temperature cycle, and this increased rapidly with the PVA fraction larger than 0.5. The E' increased with increase of PVA fraction, but below certain fraction of PVA (about 0.4), the blends of PVA and gelatin did from gels showing phase separation. Then the mixed gels formed xerogels with the PVA fraction smaller than 0.1. The melting temperature of mixed gels increased with increasing number of temperature cycle. From these results, the effect of freezing time on E' of mixed gels is explained through the formation of microcrystalline within the gels.

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Gas chromatographic method was established for the simultaneous quantitative determination of 9 kinds of volatile fatty acids, lactic acid, and furfural in silage. They were separated within 16min on a 1.5m 1% KT-300 on Chromatobase AF, 40-60 mesh glass column. Column temperature was elevated from 120 to 190°C (5°C/min). Usually, it was necessary to add 0.05-0.10% H₂SO₄ to aqueous extract from silage as telephthalic acid solid support was used. But, the addition of H2SO4 was not necessary by using this column. The coefficient of variation for these components ranged from 2.08-2.74%, Unknown component in brewers grain silage extract was identified as furfural with GC-MS.

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Ascorbic acid (AsA) content of several kinds of vegetables including chilling sensitive (CS) and insensitive (CIS) were determined during storage at 1°, 5° and 20°C. Contents of AsA and Total AsA (AsA+dehydro AsA) in cucumber (CS) decreased continuously at 5°C. On the other hand no decrease was observed at 20°C. AsA content in winter squash (CS) started to decrease only after occurrence of chilling injury (CI) during storage at 1°C. In the case of sweet potato (CS), AsA content decreased in the browning part with CI, but no trend of decreasing was observed in healthy part during storage at 5°C. On the other hand, there was no decrease in AsA and dehydro AsA content in potato (CIS) stored at 1° and 5°C.

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Near infrared reflectance (NIR) technique was used to determine moisture, protein and ash contents in 60% extraction flour samples from home-grown wheat harvested over 3 years (1979-1981). In order to ascertain a feasibility of an universal calibration set, a performance of the calibration developed using the 37 flour samples from the 1980 wheat was evaluated. It is concluded that standard error of difference between standard-analytical and NIR predicted values are in the range of acceptable limits except ash measurement, which means that the NIR technique is applicable to a routine analysis, however, a further study should be conducted to solve the problems with ash measurement and an annual bias adjustment in the instrument.

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