Multilayer laminated films may contain organic solvents derived from adhesives, printing inks and so on. A headspace-GC/MS analysis method for the simultaneous determination of 30 substances such as toluene, xylene, acetone, methyl ethyl ketone, ethyl acetate, butyl acetate, methanol, ethanol, was developed. A N,N-dimethyl formamide solution containing an internal standard substance was added to the sample. After leaving overnight at room temperature, the headspace gas was analyzed by GC/MS. This method was applicable to a laminate film made of various materials. The organic solvents such as toluene, ethyl acetate, and heptane were detected from 6 out of 42 food packaging bags made from laminated film on Japanese market using this method.

The Japanese Food Sanitation Act designates the evaporation residue test as a specification for plastics that intended to contact with foods. The test conditions and migration limits for oils and fatty foods were considered on the basis of the results obtained from the evaporation residue test according to the Japanese Act and the overall migration test into olive oil according to EN1186-2. The evaporation residue test was conducted using heptane at 25℃ for 1 hour. The results of most samples were under 30 μg/mL although those of high impact polystyrene,polymethylpentene and polyvinyl chloride were found to be over 30 μg/mL. However, these results were within the acceptable range of the relaxed limits (240, 120, 150 μg/mL). Regarding the overall migration into olive oil, most plastics were under the determination limit at 60℃ for 30 min. But the results for polyethylene, polypropylene and polyvinyl chloride were over 30 μg/mL at 95 and 121℃, which were higher than their evaporation residues. In other words, the existing test conditions and limits of the evaporation residue test could be used for testing plastics that come into contact with oils and fatty foods at lower temperatures. However, they are not adequate for evaluating some plastics that come into contact with oils and fatty foods at higher temperatures.

Microbial colony counts of concern of food products are one of the most important items in microbiological examinations. The distributions of colony counts per agar plate of food samples are considered to be reflected with microbial cell distributions in food homogenates. However, (i) the probabilistic distributions of the colony counts per agar plate at the dilution of counting and (ii) the relationship between the colony counts per plate and the number of agar plates for food samples have not been intensively studied so far. In this study, therefore, these two points were studied with raw food samples of raw minced beef and chicken and raw milk and microbial culture samples of Escherichia coli, Staphylococcus aureus, and Saccharomyces cerevisiae. Among four major probabilistic distributions, it was found that aerobic plate counts per plate of the foods were well described with negative binomial, Poisson, and normal distributions and that the colony counts per plate of microbial cultures were described well with binomial, Poisson, and normal distributions. The effect of the number of agar plates on the estimation of the mean of colony counts per plate of a sample was then studied with the data randomly resampled from the experimental data. The resampled data showed that with more number of plates the mean of counts fluctuated less and the coefficients of variation of colony counts per plate decreased further, which were coincident to the estimated by the central limit theory. Our study would provide useful information on the characteristics of colony counts per plate of food samples which are routinely examined.

LC/Tribrid Orbitrap was developed to determine phosphodiesterase-5 (PDE-5) inhibitors and their analogs as adulterants in dietary supplements. High-resolution MS/MS and MS³ spectra of PDE-5 inhibitors and their analogs were obtained by LC/Tribrid Orbitrap using both higher-energy collisional dissociation and collision-induced dissociation. We investigated dietary supplements that claim to enhance men’s sexual performance, and detected PDE-5 inhibitors and their analogs. We also estimated the structures of the PDE-5 inhibitor analogs and the impurities of PDE-5 inhibitors and their analogs in the dietary supplements.

Assuming the intentional adulteration of beverages with plant toxins, an LC-MS/MS method for the simultaneous determination of 18 plant toxins (lycorine, galantamine, ricinine, scopolamine, gelsemine, atropine, colchicine, α-solanine, jervine, α-chaconine, veratramine, mesaconitine, digoxin, protoveratrine A, aconitine, hypaconitine, oleandrin, and digitoxin) was developed. As analytical samples, beer, distilled spirits, blend tea, ready-to-drink (RTD) coffee, and fermented milk drink were selected. The extraction and purification of the analytes were performed using modified QuEChERS method. Method validation in terms of intra-day precision, accuracy, and extraction recovery obtained satisfactory results. The calibration curves for the analytes were linear from 5 to 200 ng/mL (r>0.990), which enabled the determination of toxins in even trace amounts.

We evaluated measurement uncertainty and performed internal quality control of an ELISA test for allergens in egg and milk, using control samples. For the evaluation of measurement uncertainty, the following three important factors were identified: 1) Differences in test-kit lots, 2) Different-day reproducibility, 3) Same-time reproducibility. A three-stage nested design was used, and the combined standard uncertainty of the three factors mentioned above was calculated based on the results obtained. Measurement uncertainty was defined as the expanded uncertainty obtained by multiplying the combined standard uncertainty by a coverage factor of two. As a result, the expanded uncertainty of egg was 1.9 μg/g when the total egg protein concentration was 13.4 μg/g, and the expanded uncertainty of milk was 1.8 μg/g when the total milk protein concentration was 13.5 μg/g. For the internal quality control, we first set the reference range of the measured value of the control sample, using the obtained combined standard uncertainty as an index. Each control sample was then measured for every test, and we concluded that the test was performed without any errors, when the result of the control sample was within the reference range. Second, the measured values of the control samples were plotted on a graph for continuous monitoring. This enabled us to check whether inspection accuracy was maintained. There were no large chronological changes and no major differences between the standard deviations of the control samples and the combined standard uncertainty in egg or milk. Therefore, it was determined that the dispersion was at an acceptable range and inspection accuracy was maintained.

Foods with Function Claims are allowed to label health claims based on scientific evidence evaluated by the manufacturers. To prevent health problems caused by inadequate use, the manufacturers should label proper safety information. To evaluate whether safety information is sufficiently provided, we conducted the adverse event review focused on popular functional ingredients using the database; Information system on safety and effectiveness for health food. The data suggested that causal factor of adverse events related to products containing soy isoflavone, ginkgo biloba extract and docosahexaenoic acid/eicosapentaenoic acid were overdose intake, concomitant use with certain medicines, and use by whom with an allergic predisposition. However, the safety information on the label was insufficient to prevent adverse events on each products’ label. It is important not only to encourage food manufacturers to provide sufficient information based on safety review, but also to inform consumers about adverse events.