The analytical method for antimony (Sb) and lead (Pb) in pewterware, which is a tin alloy product, was examined and its commercial products were surveyed. The sample was dissolved in HCl-HNO₃ (3:1) and diluted with water and 0.1 mol/L HNO₃. It was analyzed by the calibration curve method using tin-added standard solutions or by the standard addition method. They were determined by ICP-MS, ICP-AES and GFAA. The recoveries were 96-114%. In the case of ICP-MS, the test solution should be diluted adequately and the probe and tube of the auto-sampler should be rinsed out sufficiently in order to reduce the tin and Sb adsorption. X-ray fluorescence spectrometry also produced good results. Commercial pewterwares contained Sb at 0.6-4.0% and Pb at nd-0.09%. These levels are below the maximum limits of the Japanese Food Sanitation Law. Sb and Pb were released at levels of 5-73 ng/mL and 2-30 ng/mL into 4% acetic acid at 60℃ after 30 min, respectively, while they were not released into water.

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A simple and efficient method has been developed for determining of the amount of racemic α-amino acids in beverages by chiral ligand exchange chromatography with ultraviolet detection. The chromatographic resolution of racemic α-amino acids was performed on a reverse-phase octadecyl silica gel column coated with N,S-dioctyl-D -penicillamine, Sumichiral OA-5000 (particle-type), using cupric sulfate as a mobile phase additive. The mobile phases A and B contained aqueous 2 mM CuSO₄ solution and 2 mM CuSO₄ in water and acetonitrile (85 + 15, v/v), respectively. The injection volume, flow rate, and column temperature were 20 μL, 0.8 mL/min, and 17℃, respectively. A UV absorbance detector was set to 254 nm. Gly and nine D,L-amino acids (Lys, Arg, Ala, Pro, Val, Asp, Ile, Leu and Glu) were resolved with good separation factors, with the exception of L-Ala and D-Arg. The overlapping peaks of L-Ala and D-Arg were resolved by using the combination of a particle chiral ligand exchange chromatography (CLEC) column and a monolithic CLEC column. The elution orders were fairly consistent, and the D-enantiomers were retained for a time longer than the L-enantiomers on the column. The calibration graphs were linear in the range of 5-100 μg/mL. The recovery of the compounds added to the beverages at the 50 μg/mL level was >98%, and the limit of quantification values was found to be 5 μg/mL for the nine D-amino acids. Eight commercial beverages were analyzed by the proposed method. Although D-Val was detected in a sample, by using LC-MS, it was proved that the peak was not due to D-Val.

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Since epidemiological investigations in Japan have shown that the number of patients with a crustacean allergy, such as that to shrimp and crabs, has increased, the Ministry of Health, Labor and Welfare in Japan has formulated a plan to make labeling of these crustaceans mandatory in 2008. In this survey, the content of crustacean soluble protein was investigated in 305 food ingredients using two kinds of ELISA systems. Consequently, the crustacean soluble protein was detected in 137 food ingredients (seaweeds, 27 samples; sardine fries, 48 samples; ground fish fleshes, 59 samples; bivalves, 3 samples). These results clarified that those food ingredients could contain crustacean species as unintentional contamination, and that the detection rate and level of crustacean soluble protein in sardine fries and ground fish flesh are especially high. Therefore, the study suggests that the possibility of contamination of crustacean species may be declared on the label to avoid the food allergies for the consumer. These data would be the reference report of the labeling system in the food ingredient stage.

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The purpose of this study was to develop low cost color indicators of temperature abuse in the cold chain. To develop the indicators, bacterial strain sk22 isolated from commercial cod was used. Strain sk22 can grow and produce acid from carbohydrate at 4℃. Incubating sk22 in modified Oxidation- Fermentation broth at 12℃ (with initial inoculums levels of 10⁶ and 10³ CFU/ml) resulted in color changes of 35 and 72 hours respectively. Further, addition of buffer delayed color changes. Therefore by adjusting inoculum levels and/or buffer concentration, timing of color change could be controlled. To make the indicator safe for food use, the suitability of nine pigments and food grade buffers was tested to judge their effects on the color change. Red cabbage pigment was the most suitable one of the tested pigments because color change was clear. Furthermore, addition of food grade ammonium sulfate as a buffer enhanced clarity of color change.

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In Europe, semicarbazide (SEM) was determined in bottled foods including baby foods. SEM is a thermal degradation products of azodicarbonamide (ADC) which is a foaming agent for plastic gaskets on metal lids. In this paper, an analytical method of SEM and hydrazodicarbonamide (HDC) which is also an intermediate degradation product of ADC was established in gaskets. Then SEM and HDC in 92 gaskets of bottled foods were surveyed on Japanese market. SEM was detected 0.1-2.3 μg/g (ave. 0.9 μg/g) in 55 samples and HDC was detected 5.6-269 μg/g (ave. 113 μg/g) in 58 samples. Neither SEM nor HDC was detected in 32 samples. All of foamed gaskets contained SEM and/or HDC. Most of gaskets on press-on twist-off (PT) caps and screw caps contained SEM and/or HDC, while that on 2/3 of lug caps contained no SEM nor HDC. These results indicate that ADC is used widely as a foaming agent of the seal gasket in Japan.

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A high sensitive and simple method for the determination of chromium in fluid food for medical care and grains was examined by using a technique of graphite furnace atomic absorption spectrometry. The fixed-quantity limit for each sample was 1.0, μg/100g(=10ppb), and 20 samples were determined only within a day. There was little interference by coexisting elements (ex. sodium, phosphorus, potassium and calcium), even in the presence of 100,000 double concentrations. The result of the recovery test showed a good consistence with the reference value of the standard sample (CRM). It was therefore judged that present method could be practically employed as a highly sensitive and simple method for the determination of chromium. The fixed-quantity limit could be set lower, if the level of contamination was reduced. The chromium concentrations were 1.3-10.3 μg /100g in fluid food, 0.8-3.7 μg /100g in fortification food, 1.4-22μg /100g in grains.

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A simple and rapid method for determination of aspartame(APM) in foods using Cation-Exchange and Reversed-Phase Cartridge, and high performance liquid chromatography(HPLC) was developed. APM in a sample was extracted with 0.01 mol/L hydrochloric acid in ultrasonic bath, and the extract was loaded onto an Oasis MCX, cation-exchange and reversed-phase cartridge. The cartridge was washed with water followed by methanol - acetonitrile (1:1), and APM was eluted with 5 % sodium chloride - methanol - acetonitrile (3:1:6). The eluate was evaporated to remove organic solvents, and the residue was made up to a volume of 10 mL with water. APM in this solution was chromatographed on a Inertsil ODS-SP (4.6 mm i.d. × 150 mm) column with 0.02 mol/L phosphate buffer, pH 5.0, - methanol (3:1) as the mobile phase and detected with an ultraviolet detector at 210 nm. The recoveries of APM from 12 kinds of food added at the level of 0.02 g/kg and 0.10 g/kg were 90〜100 %. The detection limit was 0.01 g/kg. We examined 13 kinds of commercial food samples labeled to contain APM by the proposed method. The quantitative values of APM in tested samples were 0.07〜12 g/kg.

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