Benzene, a harmful solvent, was prescribed in the Japanese standards of food additives 6th edition (JSFA VI) as the solvent for indicator for the nonaqueous titration of potassium sorbate. It is better that the benzene is changed to a slightly noxious solvent. In this paper, we carried out two cases of the titrimetric analysis of potassium sorbate; in the case using the benzene as the solvent for indicator and in the case using the acetic acid for nonaqueous titration as that, according to the method in JSFA VI, to make clear whether the benzene is changeable to a slightly noxiuos solvent, acetic acid, or not. The results were shown in Table 1. No significant differences were observed between both titration results, suggesting the benzene is changeable to the acetic acid for nonaqueous titration.

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The ability of synthetic Boehmite to remove and adsorb phosphate ions from two kinds of soy sauce was investigated. Boehmite was added to soy sauce samples and the concentration of phosphate ions and other substances in the filtrates was measured after filtration. The Boehmite adsorbed phosphate ions efficiently, this ability increased with the volume of Boehmite and treatment time. The aluminum ions and sulfate ions in both soy sauce samples increased slightly after this treatment but the total nitrogen and sodium chloride did not change. The fact that little aluminum dissolved in the soy sauce during the Boehmite treatment may be because soy sauce was only slightly acidic. In addition, the mechanism of Boehmite on the removal of phosphate ions from soy sauce involves not only physical adsorption but also the ion exchange effects of the Boehmite. Because a small amount of sulfate impurity in the Boehmite was exchanged by phosphate ions and dissolved in the soy sauce. These results indicate that synthetic Boehmite is a useful substance for removing phosphate ions from soy sauce with few effects on other ingredients and inorganic ions.

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Residue levels of 7 pesiticides after cooking processes were investigated for domestic crops (komatsuna, green pepper, onion, Chinese cabbage, apple, strawberry and kiwi fruit). As shown in Table 1, both captan, chlorpyrifos and fenitrothion in raw apples and kiwi fruits were almost completely removed by peeling. Jamming removed 59.1-100% of captan and chlorpyrifos from apples, while 11.4-88.2% of captan, endosulfan and propanil from strawberries. It was found that diazinon in komatsuna, endosulfan in green pepper, propanil in onion and EPN in chinese cabbage were differently decreased by boiling, roasting and frying, possibly owing to the differences of affinity between these pesticides and matrices of crops.

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The change in the colour of fresh fish, following exposure or non exposure to carbon monoxide (CO) gas, was measured with a colour tester at various time intervals over a 7-day period. The pattern of colour change varied depending on the species of fish. The colour of the fish exposed to CO gas was appreciably different from that of the unexposed fish. Next, the effect of a exposure to CO gas on the freshness index (K value) was studied by leaving the fish to stand at 5℃ and examining the change in K value at various time intervals. The results revealed no significant difference in the mean of K values betwen the two groups (or populations) at a significance level of α=0.05. It was concluded that a exposure to CO gas has no effect on maintenance of freshness.

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In this study, in order to develop a hypollergenic soybean product, the change of the content of an allergenic protein, Gly m Bd 30K, in soybean during natto fermentation in a natto manufacturing factory was investigated by the immunological methods with anti-Gly m Bd 30K antiserum. For the preparation of the anti-Gly m Bd 30K antiserum, was purified from the defatted soybean meal by extraction, isoelectric precipitation at pH6.4, ammonium sulfate fractionation (40% saturation), Sephacryl S-400 and Cellulofine GCL-1000sf gel filtrations (Fig. 1), and HiTrap Q ion-exchange chromatography (Fig. 2A). The purified Gly m Bd 30K was separated into two bands with the molecular weights of approximately 33,000 and 31,000, respectively on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (Fig. 2B). Both bands were identified as Gly m Bd 30K by the N-terminal amino acid sequence analysis. Then, the carboxymethylated Gly m Bd 30K was immunized to two rabbits and after eight weeks, anti-Gly m Bd 30K antisera were obtained. By immunoblotting with the anti-Gly m Bd 30K antiserum, the allergenic protein was detected in Hikiwari soybean fermented for 0-9hrs, but not in Hikiwari soybean fermented for 10-17hrs (Fig. 3). The contents of Gly m Bd 30K in both Hikiwari and Kotsubu natto were reduced to 1-5% of that of the unfermented soybean after the fermentation for 10hrs or longer(Fig. 4). By an immunoblotting technique with the serum of a soybean-sensitive patient with atopic dermatitis, one of the major allergenic proteins of soybean with the molecular weight of approximately 69,000, could not be detected in Hikiwari natto fermented for both 10 and 17hrs (Fig. 5). From these results, it was suggested that Hikiwari natto fermented for 10-17hrs in the natto manufacturing factory was suitable for the preparation of the hypoallergenic soybean product.

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Ten strains of fungi belonging to the genera Deutromycetes were isolated from soil samples containing a soil fertilizer "Binekiton". These microbes were classified into four groups of Aspergillus, Parcilomyces, Penicillium and Scopulariopsis. The predominant and the most fast-growing fungus Scopulariopsis brevicaulis (Sacc.) Bainier MIB301 was identified and studied in detail for morphological and physiological characteristics. MIB301 caused tissue maceration of potato tubers, which phenomenon was attributed to the activity of the pectolytic enzymes derived from the strain.

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The nitrate contents in 8 beet red products available commercially in Japan were analyzed as a part of studies for establishing the specifications of natural food additives. As the analytical method, ion-chromatography was considered suitable and was, therefore, used. The nitrate contens in 3 products exceeded to limit value of JECFA specifications. Therefore, it is considered that, when the limit value is adopted in The Japanese Standards for Food Additives, some products may not comply with the specification, if the manufacturing processes are unchanged.

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The contents of 2-acetyl-4-tetrahydroxybutylimidazole (THI) in commercial caramel I, III, and IV were determined as the data used to establish the specifications of caramel colors. In caramel III, which is obtained by adding ammonium compounds, all products contained THI in the range of 0.72-7.3μg/g. However, in caramel IV, which is obtained by adding ammonium and sulfite compounds, no products contained THI. On the other hand, in caramel I, which contains neither ammonium nor sulfite compounds, a tiny peak that may be THI was observed in 1 product.

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For prevention of geriatric diseases, we conducted a health program, in which nutritional education and physical exercises were performed, for 21 middle-aged women. Body fat ratio decrease after the program, while body weight and body mass index were not changed. Total serum fatty acid concentration decreased from 5.6 mg/ml to 4.5 mg/ml. Serum saturated fatty acid composition also decreased from 30% to 28% while serum n-6-polyunsaturated fatty acid composition significatry increased from 33% to 35%. If serum saturated fatty acid composition was increased, HDL-cholesterol concentration in serum was decreased. But if serum polyunsaturated fatty acid composition was increased, HDL-cholesterol concentration in serum was also increased. Moreover, if the total serum fatty acid concentration was decreased, the total cholesterol and triglyceride concentrations in serum were decreased.

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Turmeric oleoresin is a natural food color used worldwide. Its principal pigment is curcumin, and demethoxycurcumin and bisdemethoxycurcumin are also constituents. In this report, the photo-stability of curcumin reagent, turmeric oleoresin preparations, and a turmeric preparation used as food color was examined and the following results were obtained. 1) Based on the quantity ratios of 3 pigments and the presence of non-coloring constituents, the preparations including a turmeric preparation were divided into 2 categories. 2) It was difficult to detect 3 spots of the pigments by TLC chromatography using a microcrystalline cellulose plate. 3) On photoirradiation, the curcumin reagent was relatively stable in alcohols among various solvents. 4) After the photo-irradiation of curcumin reagent, a cyclisation product of curcumin was detected, as well as decomposed compounds such as vanillic acid. vanillin, and ferulic acid. 5) The photo-stability was not different among the preparations. 6) The photo-decomposed compounds were not detected in any of the preparations.

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An analytical method for ctrinin in a natural colour, Monascus colour, was studied. As the pretreatment, the TLC method was not useful due to low recovery rates. When a powdered sample was subjected, the Rf value of ctrinin was influenced by co-existing dextrin. The use of 8 kinds of solid-extraction cartridges for the extraction of citrinin was also not effective. However, pretreatment with the Daiaion HP20 column was satisfactory for citrinin extraction. The recovery of citrinin was more than 90%. Moreover, the detection limits of the HP20 column pretreatment-HPLC method were 0.2μg/g for liquid samples and 2μg/g for powdered samples.

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Nitrate is allowed to be used in meat products and whale meat bacon as a color fixative, and in cheese and Japanese rice wine (sake) as a fermentation moderating agent, while nitrite is allowed as a color fixative. Safe range for intake of food additives are expressed as ADI (acceptable daily intake, in units of mg of additive/day/kg of body weight). An actual study of personal daily intakes of nitrate and nitrite by Japanese people makes comparisons with the ADI possible, thus confirming whether intakes are within safe levels. The authors have studied the daily intakes of both nitrate and nitrite (additives which are normally present as constituents in foodstuffs) in Fiscal year 1995-1996 in Japan. In 1995, processed foods of 344 articles and in 1996, fresh foods of 132 articles were the objects of the study. They were classified into seven groups i.e. seasonings and beverages (group 1), cereals (group 2), potatoes, pulses, nut and seeds (group 3), fish shelfish and meat (group 4), fats, oil and dairy products (group 5), sugars and confectioneries (group 6) and fruits, vegetables and algae (group 7). Table 1 shows the results of the present study. In the years 1995 and 1996, daily intakes of nitrate were 39.58 and 192.49 mg/day, and of nitrite were 1.08 and 0.07 mg/day, respectively. The highest intake of nitrate was found to be from fresh food in group 7 (fruits, vegetables, mushrooms and seaweeds). In the present study, no significantly different intake pattern was found among regions of western, central and eastern Japan. The daily intake of nitrite was 38% of the ADI. In contrast to nitrite, the daily intake of nitrate extended up to 125.5% of the ADI. However, it was clearly suggested that most of the substance was taken from fresh foods which contained nitrate as normally occurring ingredient.

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To investigate antibacterial action of fermented milk against enterohemorragic Escherichia coli O157:H7 (O157), overnight culture of clinically isolated O157 cells of two strains (NGY10 and 33) were incubated at 37℃ with a liquefied yoghurt product and survival of the cells were monitored by CFU assay with Desoxycholate agar plate. After the incubation, viable O157 cells in the product dramatically decreased by 4-5 logs after 7 h and could not be detected by 31 h. This bactericidal activity was not affected when lactic acid bacteria in the product were completely inactivated by heating or removed by membrane filtration. On the other hand, O157 cells in neutralized samples slightly grew in the early stage of incubation, then reversed themselves to decline by production of organic acids including lactic acid by lactic acid bacteria in the product. The skim milk solution whose pH was adjusted at 4.0 by lactic acid, also exhibited bactericidal activity. However, this phenomenon was not obvious when pH of the skim milk solution was adjusted by hydrochloric acid instead of lactic acid. These results suggest that free form of lactic acid is a major factor of the potent bactericidal activity and affects viability of O157 cells. The molecule may invade in bacterial cells through cell membrane and perturb cellular pH to become acidic. The samples represented a marked zone of inhibition against O157 by an agar diffusion method, indicating the similar effect to that obtained by the CFU counting.

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Red radish colour in foods were analyzed by using HPLC/mass spectrometry (LC/MS) and phorodiodearray-HPLC methods. Calibration curve of red radish colour using LC/MS was obtained by the total peak area of the fragment ion at m/z 271, because the main aglycon of red radish anthocyanines is peralgonidin (Mw 271). The total peak area monitored at 510 nm was used for the calibration curve by photodiodearray-HPLC. Recoveries of red radish colour from the beverage, candy, and jelly were 71〜100% (LC/MS method) and 69〜97% (photodiodearray-HOLC method) as shown in Table 1. Among 10 commercial foods containing anthocyanin colours, red radish colour was determined in a jelly at the concentration of 0.016% (LC/MS method) or 0.012% (photodiodearray-HPLC method).

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