Total of 52 food additives and food materials were screened using norovirus surrogate feline calicivirus (FCV) to assess the effect of reduction against norovirus. Over 0.01% GSE (Grape Seed Extract) ethanol solution and FCV solution mixed by 1 : 1 for 1 min at room temperature, the virus infectivity were reduced <1/1,000. We had found out the effective antiviral activity in GSE containing Proanthocyanidin.
Chicken-sashimi is a heat-seared poultry meat dish firmly established in the food culture of Kagoshima. It is now becoming widely consumed across Japan. The chicken-sashimi supplied in Kagoshima is heat-seared following carcass chilling, whereas that supplied in other regions is processed without heat-searing. Mounting epidemiological data has shown associations between non-heated-seared chicken-sashimi and Campylobacter food poisoning in most metropolitan areas, whereas chicken-sashimi-related food poisoning is rare in Kagoshima. We thus aimed to investigate the process-by-process (de-feathering, chilling, and heat-searing) dynamics of Campylobacter and fecal indicator bacterial levels in the production of chicken-sashimi from slaughtered birds at a poultry processing plant in Kagoshima. We examined 30 chicken-carcasses, and Campylobacter was detected in small quantities on the 5 samples of carcass surface after de-feathering, but was not detected in any swabs taken after chilling. E. coli and coliform were not detected, and general bacterial counts were held below 0.9 cfu/g after heat-searing, indicating that cauterization by heat-searing effectively reduced microbiological contamination of the chicken meat. This is the first report on a hygiene control strategy for chicken-sashimi, describing microbiological dynamics. Our data suggests that thorough treatment at each process enables the safe supply of chicken-sashimi for minimized risk of human infection.
In April 2018 in Toyama Prefecture, cases of foodborne illnesses possibly caused by Kudoa septempunctata were reported from eating raw flounder, amberjack, and tuna sashimi. Leftover foods and feces from two of the patients were immediately tested for K. septempunctata, but there were none detected. Therefore, we suspected the presence of myxosporean other than K. septempunctata. We performed a PCR-based test with specific primers, developed by us, to detect a wide range of 18S ribosomal DNA (rDNA) from the genus Kudoa and Unicapsula. In one of the leftover foods, amberjack sashimi, we detected Unicapsula seriolae (U. seriolae) 18S rDNA using another set of specific primers. Two rounds of PCR amplification were carried out on DNA from stool samples of the patients using both primer sets to detect 18S rDNA of the genus Kudoa or of U. seriolae. Lastly, 18S rDNA of U. seriolae was also detected in feces from the two patients by sequence analysis of the PCR products. Therefore, U. seriolae contamination was predicted to be responsible for illness in the reported cases. Additionally in this study, we were able to demonstrate the use of our PCR primer sets to screen for the genus Kudoa and Unicapsula.