[in Japanese]

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The contents of sulfate and acid-insoluble matter in commercial products of three types of carrageenan, namely purified carrageenan (13 products, PC), semirefined carrageenan (6 products, SC), and powered red algae (3 products, PA), were determined. Sulfate content was calculated from the sulfur concentration determined by ICP atomic emission spectrometry. For digesting samples, a mixture of nitric acid and perchloric acid (5:1) was used instead of nitric acid used in the previous study. The sulfate contents were 18〜36%, 16〜18%, and 16〜27% for PC, SC, and PA, respectively. The ratios of quantity of the electric charges on metals (Na, K, Mg, and Ca) and sulfate were nearly 1 in most PC products and about 1.5〜2 in all SC products. However, some products in PC also gave values near 2. Therefore, a hypothesis that the ratio might be used as a measure for purification of the products could not be verified. The contents of acid-insoluble matter were less than 1%, 8〜13%, and 9〜14% for PC, SC, and PA, respectively. Consequently, it was considered that the specification of acid-insoluble matter should be established to discriminate the type of carrageenan.

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Clean analysis has been proposed as a means of protecting the earth's environment and human health, especially that of the analysts. Certain toxic reagents such as chloroform, benzene, and mercury are still used in the official analytical methods for food additive standards. These toxic reagents should be replaced with safer reagents, or other methods should be used. Chloroform is used in the qualitative test of the bromate in potassium bromate and for the detection of contaminating bromide and iodide in potassium chloride used as a food additive. These halides are reduced or oxidized to bromine or iodine, are the free halogens produced are extracted with chloroform in the determinations. Ethyl acetate, diethyl ether, petroleum ether and n-hexane were tested as extraction solvents to replace chloroform in the above tests, and the results were compared with those obtained with chloroform. The test procedure followed the Japanese Standards for Food Additives, sixth edition, published by the Ministry of Health and Welfare of Japan. The principle of the procedures in these tests is the same as used in the Compendium of Food Additive Specifications by the Joint FAO/WHO Expert Committee on Food Additives published by the Food and Agriculture Organization, the Food Chemicals Codex of the National Research Council of the USA, and the Pharmacopoeia of Japan published by the Ministry of Health and Welfare of Japan. The color of the ethyl acetate and diethyl ether extracts was pale lemon yellow, and the color intensity of the diethyl ether and petroleum ether extracts gradually decreased, but the n-hexane extracts yielded the same results, brownish-yellow, as obtained with chloroform in the qualitative test of bromate. n-Hexane was applicable as an extraction solvent in place of chloroform to identify bromate. n-Hexane could also be used to detect bromide and iodide in potassium chloride. The optical density at the λ maximum of the n-hexane extracts was 71% of that obtained with the chloroform extract in the bromide detection test and 80% in the iodine detection test. The λ maxima of the n-hexane extracts in both tests shifted to about 10-nm longer wavelengths than with the chloroform extracts, but the color change caused by the shift in the λ maximum was not detectable with the naked eye. Chloroform could be replaced with n-hexane in the bromate qualitative test for potassium bromate and bromide and iodide detection tests for potassium chloride at 70-80% of the sensitivity obtained with chloroform.

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We estimated the per capita daily intake of condensed phosphates (CP) consisting of pyrophosphates, polyphosphates and metaphosphates with market basket system. About 340 articles of processed food were classified into following seven groups i.e. (1) Seasonings and beverages, (2) cereals, (3) potatoes, pulses, nuts and seeds, (4) fishes, shellfishes and meats, (5) fats, oils and dairy products, (6) sugars and confectioneries and (7) fruits, vegetables and algae. CP in each group were determined. Intake of CP was estimated from the concentration of CP and the amount of food in each group. (1) Daily intake of CP was 15.8mg, and that of pyrophosphates, polyphosphates and metaphosphates were 7.1mg, 3.8mg and 5.0mg respectively. (2) Most of intake came from No. 5 (6.0mg) and No. 4 (5.1mg) group. Main sources were cheese in No. 5 group and processed fish and meats in No. 4 group. The kind and amount of cheese affected intake of CP. (3) In comparison of the east, middle and west area in Japan, intake in the east and west areas were somewhat larger than in the middle area. Intake from No. 5 group in the east area was two times larger than others. For this reason it is supposed that cheese in the east area contained large amount of CP. (4) Intake of CP tends to increase, according to the survey in 1983, 1987, 1991 and 1994. (5) Intakes in the aged and schoolchild were larger than adult. Intake from No. 4 group in each generation was similar but intake from No. 5 was variable depending on the kind of cheese. Intakes from No. 6 and No. 7 in schoolchild were more than in other generation.

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The effects of washing and cooking processes on the residual levels of agricultural chemicals were examined in perishable farm products which had been experimentally spread with Dichlorvos and 19 other agricultural chemical. The level of agricultural chemicals did not significantly differ between that of vegetables after simple water washing and that of vegetables after detergent washing. When different cooking processes were compared, peeling was the most effective way to remove the chemical residue from the crops and the second most effective way was frying. Boiling was effective in reducing the level of water-soluble agricultural chemicals, and the use of oil in cooking processes markedly decreased the level of fat-soluble ones. These results demonstrate that the level of residual agricultural chemicals taken together with foods into the body is lowered considerably below the reference levels by washing or cooking them as described above.

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The use of sodium chlorite, permitted so far only as a breaching agent for cherry, coltsfoot, grape and peach, was recently expanded to a fungicide of the peels of citrus fruits for confectionery, vegetable, and egg shells. Remainder of chlorite in these foods after dipping into the agent was determined by ion chromatography (IC). The remaining chlorite in the vegetables and that on the egg shells were 40-130 ppm and 10 ppm, respectively. However, these remaining chlorites were completely removed by washing with water. Furthermore, the permeability of the agent through the egg shell was studied. It was found that no agent did permeate into the shell within 12 hours after the use at even ten fold excess of permitted dose.

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Stabilities of five kinds of sweetening agents, aspartame, sodium saccharin, glycyrrhizinic acid, stevia type 1 and stevia type 2, were estimated in four different types of processed food samles, soda drinkings (orange and root beer), half solid food (retourt custard pudding) and powdered food (soybean sauce soup for chinese noodles). Recoveries of these agents added 500 μg/g to food samples were 92.0-101.7%. Each sweetening agent added to respective food sample at the production stagew as quantitatively analyzed by HPLC on given days thereafter, and determined the remaining ratio to the added amount. Most of the sweetening agent tested remained more than 80% even 90 days later, although the stability of the agent depended on the combination with the food sample. In the retourt custard pudding, degradation of added aspartame during the production stage of the food was suggested, because the agent could not be detected any more in the food. Similarly, stevia type 2 in the pudding was indicated to interact with some components of the food. In contrast, almost all agents were shown to be stable in the powdered food.

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Sucralose, a new high-intensity sweetener, has a molecular formula of C₁₂H₁₉O₈Cl₃ and superior stability under heating and storing conditions. In order to clarify its sweetness intensity, palatability and properties, a comparison test was conducted between a simple sucralose solution and a sucralose formulation in canned coffee, fried Kamaboko (fish paste cake), noodle dip sauce, canned Shiruko (sweet red-bean soup), a carbonated drink and anon-juice jelly. The sweetness intensity and palatability were also studied by another comparisontest using aspartame, sodium saccharide and stevia. The sweetness threshold value of sucralose is 0.0006±0.00014% while that of sucrose is 0.61±0.0492%. The sweetness intensity of sucralose compared to sucrose at the sweetness threshold was approximately 1,000 times. The sucrose-equivalent concentration was found to be expressed by the following formula. y=108,24x^0.6789 y: sucrose concentration (%) x: sucralose concentration (%) The sucralose sweetness intensity depended on the kind foods. A higher sweetness intensity was observed in low pH foods or foods with a high salt content (see Figure 3). The sweetness profile in solution was evaluated as mild, with less bitterness and aftertaste than other high-intensity sweeteners (see Figure 1). When formulated in foods, it was indicated that sucralose has a similar sweetness profile to sucrose (see Figure 5), creates a better palatability in foods than other high-intensity sweeteners (see Table 4) and adds a highly palatable sweetness to a wide range of foods.

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Sucralose (Chemical name: 1,6-dichioro-1,6-dideoxy-β-D-fructofuranosyl-4-chloro-4-deoxy-α-D-galactopyranoside), is a new, high-intensity sweetener with a good sweetness profile which is approximately 600 times more powerful than sucrose, thought it is not approved yet in Japan. In order to evaluate the effectivity of sucralose, stability tests were conducted in both the production and strong processes of various food products. Though a heating process exists in the production process of canned coffee (121℃, 20 min) and that of fried Kamaboko (170℃, 3 min), no change in sucralose content was observed in either case (see Table 2). A stability test in the strong period (150 days for canned coffee, 20 days for fried Kamaboko, 30 days for noodledip sauce) showed almost no loss/100% remain rate (see Figure 2). On the other hand, another test under similar conditions was conducted using existing high-intensity sweeteners: sodium saccharide, rebaudioside and aspartame. When rebaudioside was formulated in canned coffee, more than 5% of the sweetness was lost during production was approximately 45% was lost during the storing period (60℃, 5 month). On the other hand, the sweetness from aspartame disappeared during the heating process (see Figures 4, 5, and Table 3,). From the present study, it was confirmed that sucralose is stable compared to other high-intensity sweeteners, offers good stability inproducing a wide range of food products and is effective in a wide variety of applications.

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Sucralose, a disaccharide composed of monochlorinated garactose and dichlorinated fructose, is an artificial sweetener with low calorie evaluated by Joint FAO/WHO Expert Committee of Food Additives (JECFA). The sucralose is admitted to use in several countries such as Canada, Russia, Australia and Newzealand, for beverages and cakes or ice creams. It should be urgent in Japan to have determination methods for sucralose before coming to the front of imported food. We established a simple, rapid and sensitive method for determination of the sugar using ion chromatography with a pulsed amperometric detector. The calibration curves were linear at levels ranging from 0.1 μg/ml to 10 μg/ml, which was 50 and 500 times more sensitive than the refractive index and UV methods, respectively. The recoveries of the sucuralose obtained from sample spiked with 100 to 600 μg/g were 73.2-98.0%.

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Discriminative methods for determination high-test hypo-chlorite (Ca(ClO)₂ as a main component) and sodium chlorite (NaClO₂) as food additives were described. The quantity of calcium contained in samples was determined by chelatometric titration using disodium ethylenediaminetetraacetate (EDTA) after high-test hypo-chlorite was allowed to react with acetic acid. Sodium insamples was determined by flame-spectrophotometry at 589 nm. Determination of hypo-chlorite and chlorite was carried out by two-step iodometry. The coefficient variations of data obtained by these methods were less than ±2% on repeated runs. Although molar concentration ratios of calcium in high-test hypochlorite was higher than those of anions, and were not constant, disctiminative determination of high-test hypo-chlorite and sodium chlorite in their mixed samples was possible by use of the two-step iodometry. These methods were useful for the discriminative determination of these breaching and bacteriocidal agents.

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