Detection of Gamma-Ray Irradiation History of Dried Plant-Based Foods via the Analysis of 5,6-Dihydrothymidine
Shokuhin Eiseigaku Zasshi. 2023;64(6):206-213. doi: 10.3358/shokueishi.64.206.ABSTRACTIrradiation is widely used worldwide to sterilize and kill insects in food, and prevent the germination of agricultural products. However, in Japan, food irradiation is prohibited except to prevent potato sprouting. Herein, 5,6-dihydrothymidine (DHdThd) residue-a damaged nucleoside generated from the thymidine (dThd) residue in DNA contained in food upon irradiation-was used as a detection indicator. Eight dried plant-based food samples were gamma ray-irradiated in the range from 3.2 to 8.3 kGy. Subsequently, DNA was extracted from the ir...
Source: Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan - January 3, 2024 Category: Food Science Authors: Naoki Fukui Takuya Fujiwara Masakazu Furuta Satoshi Takatori Source Type: research

Quantitative Survey of Campylobacter on Chicken Livers in Japan
Shokuhin Eiseigaku Zasshi. 2023;64(6):214-217. doi: 10.3358/shokueishi.64.214.ABSTRACTChicken liver is a potential source of campylobacteriosis in humans. Therefore, we determined the number of Campylobacter in chicken liver. In total, 33 vacuum-packed liver products were obtained from retail stores, and found that 27 of the 33 products (81.8%) were contaminated with Campylobacter. Moreover, Campylobacter was isolated from 138 of 149 livers (92.6%) collected from the 27 Campylobacter-positive products. The mean Campylobacter count was 2.3 log10 CFU/g, while Campylobacter count in 22 of the 138 contaminated livers (15.9%) w...
Source: Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan - January 3, 2024 Category: Food Science Authors: Yoshimasa Sasaki Kenzo Yonemitsu Yoshika Momose Masashi Uema Source Type: research

Investigation of Genetically Modified Maize Imported into Japan in 2021/2022 and the Applicability of Japanese Official Methods
In this study, we investigated whether current Japanese official qualitative and quantitative methods (the current official methods) for GM maize can comprehensively target events in domestically distributed maize. For samples with the identity-preserved (IP) handling system and non-IP samples from the United States (US) and non-IP samples from Brazil, we performed event-specific real-time PCR targeting 25 authorized single GM maize events in addition to the current official methods. According to our results, 15 events targeted by the current official methods were detected, but insect-resistance (IR) Event5307 and herbicid...
Source: Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan - January 3, 2024 Category: Food Science Authors: Keisuke Soga Chie Taguchi Miyu Sugino Tomohiro Egi Jumpei Narushima Satoko Yoshiba Reona Takabatake Kazunari Kondo Norihito Shibata Source Type: research

Storage Stability of Nitrite in Nitrite Analysis of Meat Products
Shokuhin Eiseigaku Zasshi. 2023;64(6):226-231. doi: 10.3358/shokueishi.64.226.ABSTRACTFor the analysis of nitrite ions in food, the stabilities of nitrite ions in meat products and their standard solutions were evaluated. Nitrite is easily oxidized or reduced; hence, products with standard solutions or colour retention agent must be carefully handled. To assess the stability and decreasing trend of nitrite, we examined the storage stability of standard solutions using calibration curves, the time course of nitrite in chopped meat products stored under different conditions, and the time course of nitrite in the sample solut...
Source: Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan - January 3, 2024 Category: Food Science Authors: Sumiyo Yamamoto Shoichi Tahara Etsuko Ishii Yuko Takagi Chigusa Kobayashi Source Type: research

Color Reaction Identification of Omphalotus guepiniformis Causing Food Poisoning
Shokuhin Eiseigaku Zasshi. 2023;64(6):232-235. doi: 10.3358/shokueishi.64.232.ABSTRACTSimple identification using a color reaction was applied to investigate poisoning, putatively caused by Omphalotus guepiniformis. Some leftover uncooked mushrooms had turned turquoise green when a beam reagent (5 w/v% potassium hydroxide ethanolic solution) was dripped onto the mushroom pileus. Furthermore, ethanol extract of the mushrooms exhibited the same color reaction. Then, illudin S, a toxic compound contained in O. guepiniformis, was detected in uncooked leftover mushrooms using LC-MS/MS analysis. Therefore, this case was inferred...
Source: Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan - January 3, 2024 Category: Food Science Authors: Hideyuki Shinohara Ryuma Okawara Ikuko Ito Yoshitaka Ishida Kosuke Ota Yuka Nagaoka Source Type: research

Tetrodotoxin Content of the Small Gastropod Nassarius sufflatus
In this study, we investigated the TTX content of the muscles and viscera of Nassarius sufflatus collected off the coast of Futaoi Island, Shimonoseki, Yamaguchi Prefecture, Japan, to prevent the occurrence of TTX poisoning caused by this small gastropod. Live specimens were obtained, and their muscles and viscera were collected. Test solutions were prepared from tissues of specimens and analyzed for TTX by HPLC-fluorescence detection. TTX was detected in both tissues at concentrations ranging from <0.1 to 18.2 μg/g for muscle and <0.1 to 130.7 μg/g for viscera. These results suggested that N. sufflatus accumulates...
Source: Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan - January 3, 2024 Category: Food Science Authors: Ryohei Tatsuno Ryo Yamasaki Kai Mizokami Genki Hayashi Tsubasa Fukuda Manabu Furushita Hiroshi Takahashi Takayuki Sonoyama Shigeo Hori Source Type: research

Validation of Method for Nitrite Determination in Foods
Shokuhin Eiseigaku Zasshi. 2023;64(6):240-245. doi: 10.3358/shokueishi.64.240.ABSTRACTIn general, nitrite in food is extracted under slightly alkaline conditions, deproteinized, and analyzed by a colorimetric method using color development by diazotization. However, depending on the sample, the sample solution may become cloudy and difficult to filter by the deproteinization treatment of the analytical method. Recently, an improved analytical method that solves these problems has been reported. Therefore, a validation study was performed on the improved analytical method was performed. The concentrations of sodium nitrite ...
Source: Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan - January 3, 2024 Category: Food Science Authors: Kyoko Sato Shoko Terami Takahiro Sasaki Hikaru Sakurai Akira Shimoyama Haruko Sekido Shoichi Tahara Takahiko Hara Takudo Ito Shinji Yamamoto Mika Yoshida Takahiro Watanabe Chiye Tatebe Hiroki Kubota Atsuko Tada Source Type: research

Simultaneous Determination of Pesticide Residues in Brown Rice Using GC-MS/MS and LC-MS/MS
This study developed a method that simultaneously detected 283 pesticide residues in brown rice using GC-MS/MS and LC-MS/MS. In this method, we examined the desirable amount of sodium chloride required for salting out and the SPE cartridge required for clean-up. Pesticide residues from the sample were extracted with acetonitrile using a homogenizer and mixed with salts including anhydrous magnesium, two types of citrate, and sodium chloride. The sample solution of the acetonitrile layer was cleaned up using the GCB/NH2 (200 mg/200 mg, 6 mL) SPE cartridge. The determination method was validated using two concentrations (0.0...
Source: Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan - January 3, 2024 Category: Food Science Authors: Yoshie Kokaji Sanae Tomizawa Kyoko Kamijo Takayuki Nakajima Kazuoki Yamamoto Yuri Saito Tomomi Takada Hiroko Shiradoh Yoshihiro Ohsawa Ayane Oyama Maiko Noguchi Tomoko Yokoyama Takeo Sasamoto Source Type: research

Method Improvement for Quantitative Analysis of Chlorophyll Degradation Compounds, Including Pheophorbide, in Chlorella Products
In this study, we thoroughly examined each step of the official method to enhance the operability and develop an alternative method that eliminates the need for saturated sodium sulfate solution. The developed method was evaluated for pheophorbide a and pyropheophorbide a at 100 mg%. Satisfactory analytical performance was achieved with trueness of 100% for pheophorbide a and 90% for pyropheophorbide a, and relative standard deviations of intra- and inter-day precision below 5% for both compounds. The proposed method is considered suitable for regulatory analysis of chlorophyll degradation compounds and would be useful for...
Source: Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan - January 3, 2024 Category: Food Science Authors: Shizuka Saito-Shida Maki Saito Tomoaki Tsutsumi Source Type: research

Analysis of Maximum Growth Rate and Construction of Predictive Growth Model for Bacillus cereusin Mashed Potato by Calorimetric Method
Shokuhin Eiseigaku Zasshi. 2023;64(6):200-205. doi: 10.3358/shokueishi.64.200.ABSTRACTThe maximum growth rate (μmax) of Bacillus cereus was estimated using a non-destructive isothermal calorimetric method, and a growth prediction model was constructed based on the measurement results. SCD medium and mashed potato were inoculated with serial-diluted inoculum of B. cereus. Heat generation curves were determined using an isothermal calorimeter at 35, 25, and 15℃. The μmax was determined from the relationship between the increase in B. cereus cell number and incubation time, which was detected through the heat generation o...
Source: Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan - January 3, 2024 Category: Food Science Authors: Rie Togawa Satomi Kanagawa Saya Fukumoto Fia Noviyanti Yukie Hosotani Daisuke Koizumi Keishi Iohara Jun Shimodaira Susumu Kawasaki Source Type: research

Detection of Gamma-Ray Irradiation History of Dried Plant-Based Foods via the Analysis of 5,6-Dihydrothymidine
Shokuhin Eiseigaku Zasshi. 2023;64(6):206-213. doi: 10.3358/shokueishi.64.206.ABSTRACTIrradiation is widely used worldwide to sterilize and kill insects in food, and prevent the germination of agricultural products. However, in Japan, food irradiation is prohibited except to prevent potato sprouting. Herein, 5,6-dihydrothymidine (DHdThd) residue-a damaged nucleoside generated from the thymidine (dThd) residue in DNA contained in food upon irradiation-was used as a detection indicator. Eight dried plant-based food samples were gamma ray-irradiated in the range from 3.2 to 8.3 kGy. Subsequently, DNA was extracted from the ir...
Source: Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan - January 3, 2024 Category: Food Science Authors: Naoki Fukui Takuya Fujiwara Masakazu Furuta Satoshi Takatori Source Type: research

Quantitative Survey of Campylobacter on Chicken Livers in Japan
Shokuhin Eiseigaku Zasshi. 2023;64(6):214-217. doi: 10.3358/shokueishi.64.214.ABSTRACTChicken liver is a potential source of campylobacteriosis in humans. Therefore, we determined the number of Campylobacter in chicken liver. In total, 33 vacuum-packed liver products were obtained from retail stores, and found that 27 of the 33 products (81.8%) were contaminated with Campylobacter. Moreover, Campylobacter was isolated from 138 of 149 livers (92.6%) collected from the 27 Campylobacter-positive products. The mean Campylobacter count was 2.3 log10 CFU/g, while Campylobacter count in 22 of the 138 contaminated livers (15.9%) w...
Source: Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan - January 3, 2024 Category: Food Science Authors: Yoshimasa Sasaki Kenzo Yonemitsu Yoshika Momose Masashi Uema Source Type: research

Investigation of Genetically Modified Maize Imported into Japan in 2021/2022 and the Applicability of Japanese Official Methods
In this study, we investigated whether current Japanese official qualitative and quantitative methods (the current official methods) for GM maize can comprehensively target events in domestically distributed maize. For samples with the identity-preserved (IP) handling system and non-IP samples from the United States (US) and non-IP samples from Brazil, we performed event-specific real-time PCR targeting 25 authorized single GM maize events in addition to the current official methods. According to our results, 15 events targeted by the current official methods were detected, but insect-resistance (IR) Event5307 and herbicid...
Source: Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan - January 3, 2024 Category: Food Science Authors: Keisuke Soga Chie Taguchi Miyu Sugino Tomohiro Egi Jumpei Narushima Satoko Yoshiba Reona Takabatake Kazunari Kondo Norihito Shibata Source Type: research

Storage Stability of Nitrite in Nitrite Analysis of Meat Products
Shokuhin Eiseigaku Zasshi. 2023;64(6):226-231. doi: 10.3358/shokueishi.64.226.ABSTRACTFor the analysis of nitrite ions in food, the stabilities of nitrite ions in meat products and their standard solutions were evaluated. Nitrite is easily oxidized or reduced; hence, products with standard solutions or colour retention agent must be carefully handled. To assess the stability and decreasing trend of nitrite, we examined the storage stability of standard solutions using calibration curves, the time course of nitrite in chopped meat products stored under different conditions, and the time course of nitrite in the sample solut...
Source: Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan - January 3, 2024 Category: Food Science Authors: Sumiyo Yamamoto Shoichi Tahara Etsuko Ishii Yuko Takagi Chigusa Kobayashi Source Type: research

Color Reaction Identification of Omphalotus guepiniformis Causing Food Poisoning
Shokuhin Eiseigaku Zasshi. 2023;64(6):232-235. doi: 10.3358/shokueishi.64.232.ABSTRACTSimple identification using a color reaction was applied to investigate poisoning, putatively caused by Omphalotus guepiniformis. Some leftover uncooked mushrooms had turned turquoise green when a beam reagent (5 w/v% potassium hydroxide ethanolic solution) was dripped onto the mushroom pileus. Furthermore, ethanol extract of the mushrooms exhibited the same color reaction. Then, illudin S, a toxic compound contained in O. guepiniformis, was detected in uncooked leftover mushrooms using LC-MS/MS analysis. Therefore, this case was inferred...
Source: Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan - January 3, 2024 Category: Food Science Authors: Hideyuki Shinohara Ryuma Okawara Ikuko Ito Yoshitaka Ishida Kosuke Ota Yuka Nagaoka Source Type: research