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[Inactivating Effect of Heat-Denatured Lysozyme on Murine Norovirus in Bread Fillings]

Michiko Takahashi1, Yuka Yasuda1, Hajime Takahashi1

  • 1Tokyo University of Marine Science and Technology.

Shokuhin Eiseigaku Zasshi. Journal of the Food Hygienic Society of Japan
|April 27, 2018
PubMed

Insights

Murine norovirus (MNV-1) remained viable in bread fillings but heat-denatured lysozyme significantly reduced its infectivity. This suggests heat-denatured lysozyme can inactivate norovirus in food products.

Area of Science:

  • Food Microbiology
  • Virology
  • Food Safety

Background:

  • Human norovirus is a significant cause of foodborne illness.
  • Murine norovirus strain 1 (MNV-1) serves as a reliable surrogate for human norovirus studies.
  • Bread fillings can potentially harbor and transmit norovirus.

Purpose of the Study:

  • To assess the viability of MNV-1 in common bread fillings.
  • To evaluate the antiviral efficacy of heat-denatured lysozyme against MNV-1 in these fillings.

Main Methods:

  • MNV-1 was inoculated into chocolate cream and marmalade jam fillings.
  • Fillings were stored at 4°C for 5 days.
  • The effect of 1% heat-denatured lysozyme on MNV-1 infectivity was measured.

Main Results:

  • MNV-1 remained viable in both fillings during storage.
  • Heat-denatured lysozyme reduced MNV-1 infectivity immediately after addition.
  • By day 5, MNV-1 infectivity decreased by 1.2 log PFU/g in chocolate cream and 0.9 log PFU/g in marmalade jam.

Conclusions:

  • Heat-denatured lysozyme demonstrates potential as an inactivating agent for norovirus in bread fillings.
  • Further research is needed to elucidate the mechanism of action.
  • This finding has implications for improving the safety of pastry products.
Keywords:
breadfood poisoningheat-denatured lysozymeinactivationmurine norovirus

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