Partially processed carrots were prepared as two styles, lengthwise cut sections divided into two, four, or eight equal parts (1/2, 1/4, or 1/8 LCS), and crosswise cut sections with 5cm, 3cm, or 1cm thickness (5, 3, or 1 CCS). These sections and whole carrots were sealed in low density polyethylene (PE) bags (0.03mm thickness) and stored at 1°C, 8°C, or 20°C. (1) LCS samples decayed more rapidly than CCS ones at 8°C and 20°C. Decay on cut surface began to develop in xylem of LCS and in epidermal layer of CCS. The O₂, CO₂, and C₂H₄ concentrations in the PE bag during storage showed less change in CCS samples than in LCS ones, and these concentrations of 1/4 and 1/8 LCS samples changed more drastically than the others. (2) The respiration rate of carrots increased rapidly immediately after cutting, showing faster increase at 12h after cutting in 1/8 LCS, then followed by 1/4 LCS, 1/2 LCS, 1 CCS, 3 CCS, and 5 CCS in small differences. It appears that the deterioration rate depends on physiological changes associated with cutting direction. (3) The 1/4 LCS and 3 CCS were divided into phloem-cortex and xylem, and stored at 20°C. In both samples of 1/4 LCS and 3 CCS, the respiration rate after cutting in xylem was very faster than that in phloem-cortex. A difference of the cut surface area can affect the difference in these respiration rates, and it is probable that cutting influences on physiological changes of xylem more greater than those of phloem-cortex.

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In rehydration and heating process of dried Shiitake mushroom (Lentinus edodes (Berg) Sing.), the γ-Glutamyltransferase (r-GT) activity and lenthionine content were measured. In soaking and heating process, dried mushrooms were soaked in water at 5, 25 and 40°C for 5, 15 and 25h. After soaking, these mushrooms were heated for 5, 10, 20 and 40 minutes. The γ-GT activity decreased with an increase on soak temperature. It was lost almost completely after 5min of heating in the process of heating. The lenthionine content increased with increasing soak temperature immediately after the completion of soaking. However, it reached a maximum after 10min of heating regardless of conditions, and rapidly decreased after 20min of heating. The lenthionine content in mushrooms subjected to low temperature soaking increased to a larger extent for 10min of heating, and its residual amount was larger after 20min of heating. After 40min of heating, no lenthionine was detected regardless of conditions.

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The formation of fibrous structure in processed cheese was investigated using two-week ripened Gouda and eight-month ripened Emmental cheese. Commercial protein ingredients such as whey protein concentrate (WPC), egg white, sodium caseinate, and soy protein isolate (SPI) were added to the above two cheese types during cooking in order to evaluate their contribution to the formation of fibrous structure. Among these ingredients, WPC promoted the formation of fibrous structure, and a slight contribution was observed in case of egg white, while no fibrous structure was obtained when either sodium caseinate or SPI was added. Well ripened Gouda cheese was unsuitable for manufacturing fibrous cheese, since an increase of ripeness tended to decrease fibrousness even though WPC was added. On the other hand, an increase of ripeness seemed to give no adverse effects on fibrousness in Emmental type. These results indicated that such factors as type and ripeness of cheese and the addition of WPC were critical for the formation of fibrous structure in processed cheese.

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Effects of scalding temperature and cheese ripeness on the formation of fibrousness in the resultant processed cheese were investigated. The same rennet coagulum from a single milk supply was divided into three vats after cutting, and scalded at temperatures of 38°, 43°and 50°C to prepare three types of Gouda cheeses. Ripening temperature was 10°C. Each cheese was cooked at 80°C after blended with whey protein concentrate (WPC) for manufacturing the processed cheese possessing textured fibrous structure. Changes in pH, ionic calcium content and meltability during ripening were measured. When ripening time was over 5 weeks, there were small differences in these factors among the above three types and not affected by scalding temperature, although in the primary phase of ripening, a higher scalding temperature caused a higher pH, a lower ionic calcium content and poorer meltability. No significant changes in the chemical composition were caused by a higher scalding temperature as well. Fibrousness was found to be associated to a greater extent with scalding temperature. In the 2 types scalded at 38°C and 43°C, fibrousness tended to decrease with an increase of ripening although sufficient fibrousness was obtained in the primary phase of ripening, whereas in the cheese scalded at 50°C, fibrousness increased with an increase of ripening. This was possibly because a higher scalding temperature caused both a finer casein network structure and a decrease of the cleavage of α_s1-casein. It was concluded that scalding temperature was one of the critical factors in controlling the formation of fibrousness, and an employment of a higher scalding temperature possibly gave the fibrous cheese with rich flavor.

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Susceptibilities to oxidation of different molecular species of purified soybean oil triglycerides (TG) were compared in both non-catalyzed and Fe²⁺-catalyzed oxidation systems. Non-catalyzed oxidation of the sample was carried out in a beaker with continuous stirring at 37°C in the dark. Fe²⁺-catalyzed oxidation was conducted on the surface of Avicel (microcrystalline cellulose), previously coated with FeCl₂, under the conditions of 37°C and Aw 0.75. During oxidation, molecular species compositions of the samples were determined by gas-liquid chromatography. In both systems, with some exceptions, oxidation rates of the TG increased with increase in the number of double bonds in their fatty acyl chains, for molecular species having the same total carbon number in fatty acyl chains. In case of the TG having the same number of double bonds, molecular species underwent oxidation at higher rates with less total carbon numbers than with more total carbon numbers in their fatty acyl chains. However, the Fe²⁺-catalyzed system was different to some extent from the non-catalyzed system in order of molecular species of the TG susceptible of oxidation. These results suggest that, in the Fe²⁺-catalyzed oxidation, the accessibility of Fe²⁺ to the vicinities of double bonds in the fatty acyl chains of TG is influenced by differences in molecular structures of the TG.

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A method to measure the toughness of "nori" (a kind of seaweed products) by means of texturometer was examined and a method having a good correlation with the results of sensory test has been developed. It was necessary to moisten a test strip of "nori" (1.2×2.0cm large) with an artificial salivary solution (0.06ml per strip), in order to have values well correlated with sensory scores. When four moistened strips were put together and bitten by a V-plunger at clearance of 0mm, 6 bites per minute and electric power of 2.5V, values of the "fifth" peak showed good correlation with scores obtained by sensory test. The correlation coefficient was 0.938 for hoshi-nori, a sort of dried "nori", and that for yaki-nori, roasted one derived from hoshi-nori, was 0.967. This approach was proved to be useful for evaluating toughness of "nori" and applicable to both hoshi-nori and yaki-nori.

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Varying the fermentation time, black teas were produced form the tea cultivated in Indonesia (Camellia sinensis var. assamica) and the flavor of the various products was examined. A black tea extract with a fermentation time of 1h exhibited a deep color and a mild, smooth flavor. As compared with black teas produced in Sri Lanka (Uva, BOP) which are the most popular in Japan and are generally characterized by a larger content of theaflavin fraction, black teas produced in Celebes were found to contain a higher content of amino acids. But aroma components in black teas produced in Celebes showed lower level than those in Sri Lanka (Uva).

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Antioxidative activities of nasunin, isolated from Chouja-nasu (little eggplant, Solanum melongena L.'Chouja'), and of some other anthocyanins were studied by measuring their inhibitory effect on carotene oxidation induced by linoleic acid-lipoxygenase system (carotene bleaching method) and on autoxidation of linoleic acid. Nasunin showed the strongest antioxidative activity followed by malvin and rubrobrassicin when their activities were measured by carotene bleaching method at pH 7, and by linoleic acid autoxidation system at pH 2.8. Delphinindin, malvidin and cyanidin, which are aglycones of nasunin, malvin and rubrobrassicin, respectively, also showed antioxidative activities. The antioxidative activity of nasunin was stronger than that of delphinidin at pH 2.8, and the activity of malvin and rubrobrassicin showed slight difference from that of malvidin and cyanidin, respectively. These results presumably indicate that the p-coumaric acid moiety of nasunin at least partly contributes to its strong antioxidative activity.

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The effect of 11 kinds of natural pigments derived from beet, berry, beta-carotene, chlorophyll, corn, gardenia blue, monascus, onion, paprika, red cabbage and safflower yellow on the killing effect of ultraviolet (UV) irradiation toward a human histiocytic lymphoma (U-937), a U-937-derived macrophage (U-M) and a human promyelocytic leukemia (HL-60) cell line was examined. U-937 cells were more insensitive to UV irradiation than U-M and HL-60 cells. Among the pigments, only onion pigment increased the viability of the UV-irradiated cells, indicating that onion pigment had the ability to inhibit the killing effect of UV toward U-937, U-M and HL-60 cells. The inhibiting activity of onion pigment was observed in the water-soluble fraction, but not in the methanol-soluble fraction. Quercetin, a main component of onion pigment, was not effective toward inhibiting the killing effect of UV irradiation on U-937 cells.

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Protein-bound fluorescence of freeze-dried pork and egg yolk was measured during storage at 25°C by solid sample spectrofluorometry and compared with absorbed oxygen level, as well as peroxide value (PV) and 2-thiobarbituric acid (TBA) value. Fluorescences increasing with storage period were found in both the freeze-dried pork (ex. 455nm, em. 525nm) and egg yolk (ex. 425nm, em. 520nm). The fluorescence intensity showed a high positive correlation with the absorbed oxygen level although the PV and TBA values were not always correlated with it. These observations demonstrated that the fluorescence measured by solid sample spectrofluorometry could be a good indicator to estimate oxidative deterioration based on lipid peroxidation in freeze-dried foods.

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