An analytical method for the determination of zilpaterol in livestock products was developed. The sample was stirred with n-hexane and n-hexane saturated acetonitrile, and zilpaterol in the sample was extracted with acetonitrile. The extract was cleaned up on a ODS cartridge column (1 g) and SCX cartridge column (500 mg). The LC separation was carried out using an Inertsil ODS-4 column and linear gradient elution with 0.1%formic acid and acetonitrile containing 0.1% formic acid as mobile phase. Detection of MS was carried out positive ion electrospray ionization mode. Average recoveries (n=5) of zilpaterol from 6 kinds of livestock products fortified at the MRLs (0.01 mg/kg) were 87.0–99.4%, and the relative standard deviations were 2.4–6.3%. The limits of quantitation were 0.01 mg/kg.

A novel method was developed for quantification of five major piperine derivatives (piperanine, piperine, chavicine, isopiperine, and isochavicine) in a hot water extract of long pepper fruit (LPE) using the relative molar sensitivity (RMS) based on the combination of HPLC/UV and ¹H- quantitative NMR (¹H-qNMR). The RMSs of piperanine, chavicine, isopiperine, and isochavicine to piperine of which the absolute purity was determined by ¹H-qNMR were calculated to be 0.3693, 1.138, 0.9164, and 1.277, respectively. The total amount of piperine derivatives in LPE was quantified by both ¹H-qNMR and HPLC/UV based on the RMS using piperine as a single-reference material (RMS method). The relative difference in quantitation values of ¹H-qNMR and calibration curve method from the RMS method was 2.01% or less. The relative difference of the total cis–trans piperine isomers content between before and after photoirradiation in piperine solution was quantified to be 2.84% by the RMS method. In addition, the interlaboratory difference of the RMS method was confirmed in the range of 0.600 to 4.00 μg/g when analysis was performed on piperine derivatives in LPE containing tablets, while the total amount of piperine derivatives in the tablets was quantified at 606 μg/g. Our proposed method is a reliable tool for determining the contents of piperine and the derivatives in LPE and processed foods containing LPE.

Qualitative real-time PCR method for three poisonous Entoloma rhodopolium-related species in Japan was established using specific primers and FAM, VIC, Texas Red, Cy5-labeled probes. The use of multicolor probes can extend the method to simultaneous detection of different targets. Standard plasmids were constructed as reference materials. Designed primers and probes in the method detect only a target species, and the detection limit was 12.5 copies or below. This indicates it is highly specific and sensitive enough to detect the poisonous mushrooms in food residues. Next, we applied the method to four food residue samples obtained from food poisoning cases. The real-time PCR method did identify all of four samples as E. subrhodopolium and E. pseudorhodopolium, whereas PCR-RFLP did not. The method established here revealed Entoloma rhodopolium-related species in Hokkaido were different species such as E. eminens and unknown species.

It is well-known that a strange flavor, known as off-flavor, might be found in various food products. Even though these substances do not affect our body directly, they can cause a significant change in food flavor and smell, thereby lowering the quality of food products. A well-known example of off-flavor is the transfer of smell from one food product to another. We have previously studied how the smell of limonene, a flavor component of orange juice in paper cartons, is transferred from unopened packages to milk stored in paper cartons, and have confirmed cases where the milk develops a smell completely different from that of limonene. This smell was also confirmed to not have originated from orange juice, and was found to be similar to that of a halogenated phenol. This study aimed to identify this odor component, and our findings indicate the off-flavor component to be 2-iodo-4-methylphenol.

In some of the EU member countries, Hong Kong, South Korea, and Taiwan, chicken eggs contaminated by fipronil used without authorization were identified and widely reported. The Ministry of Health, Labour and Welfare of Japan stated no contaminated imports had been found in the country while promising to strengthen monitoring chicken eggs coming from those areas. Meanwhile, there are no reports published to show whether or not chicken eggs produced in Japan contain such pesticide. This paper, therefore, examined 50 commercial brands of chicken eggs produced and sold in Japan to identify 116 kinds of agricultural chemicals including fipronil.None of these brands contained fipronil. Among the 50 brands studied, 45 brands did not include any of the 116 kinds of agricultural chemicals. Spinosad was detected in the four brands with the concentration levels ranging from a trace to 0.019 ppm. Diflubenzuron was found at 0.005 ppm in one of the chicken brands. No brands exceeded the maximum residue limits.