Evaluation of survival of murine norovirus-1 during sauerkraut fermentation and storage under standard and low-sodium conditions.
Sodium reduction strategies have raised a few concerns in regards to possible outbreaks in unpasteurised raw fermented vegetables. Among potential outbreak agents, foodborne viruses are recognized as an important cause of food-borne illnesses. As most of them are acid-resistant, evaluation of the efficacy of lactic fermentation in inactivating enteric viruses must be considered to ensure the safety of these foods. In particular with the sodium reduction trend which could impair adequate fermentation in vegetables, we have challenged sauerkraut fermentation at a final concentration of 4 log TCID50/mL with the murine norovirus (MNV-1). Three sodium chloride concentrations (1.0%, 1.5%, 2.0%) were evaluated in spontaneous and starter fermentation of sauerkraut and were followed during fermentation and over a storage phase of 90 days. Detection of MNV-1 genetic material was carried out by real-time RT-PCR and the infectivity on cell culture. Real-time RT-PCR results showed that viral RNA was still detected after 90 day in sauerkraut under all the different conditions. Furthermore, MNV-1 viral particles were able to infect RAW cells after 90 days of storage with a non-significant viral charge reduction. Sodium reduction has a significant impact on the fermentation processing of sauerkraut but no influence on the destruction of norovirus particles or on their survival.
Agriculture and Agri-Food Canada, Food Research and Development Centre, 3600 Casavant Boulevard West, Saint-Hyacinthe, Quebec, J2S 8E3, Canada.
Marie-Josée
MJ
Gagné
Agriculture and Agri-Food Canada, Food Research and Development Centre, 3600 Casavant Boulevard West, Saint-Hyacinthe, Quebec, J2S 8E3, Canada.
Julie
J
Barrette
Agriculture and Agri-Food Canada, Food Research and Development Centre, 3600 Casavant Boulevard West, Saint-Hyacinthe, Quebec, J2S 8E3, Canada.
Tony
T
Savard
Agriculture and Agri-Food Canada, Food Research and Development Centre, 3600 Casavant Boulevard West, Saint-Hyacinthe, Quebec, J2S 8E3, Canada. Electronic address: julie.brassard@agr.gc.ca.
Julie
J
Brassard
D000818:Animals; D001937:Brassica / Q000737:chemistry / Q000378:metabolism / Q000382:microbiology / Q000821:virology*; D002460:Cell Line; D005285:Fermentation; D005506:Food Contamination / Q000032:analysis; D005511:Food Handling; D061353:Food Storage; D007777:Lactobacillaceae / Q000378:metabolism; D051379:Mice; D029322:Norovirus / Q000145:classification / Q000235:genetics / Q000302:isolation & purification* / Q000502:physiology; D012965:Sodium Chloride / Q000032:analysis / Q000378:metabolism; D038301:Virus Inactivation
D012965:Sodium Chloride
Fermentation; Murine norovirus; Sauerkraut; Sodium chloride; Survival study