Inactivation of natural microorganisms in litchi juice by high-pressure carbon dioxide combined with mild heat and nisin

Food Microbiol. 2012 May;30(1):139-45. doi: 10.1016/j.fm.2011.10.007. Epub 2011 Oct 14.

Abstract

The individual and combined effects of high-pressure carbon dioxide (HPCD), mild heat (MH) and nisin (200 ppm) on the inactivation of natural microorganisms, including aerobic bacteria (AB), yeasts and molds (Y&M), in litchi juice were evaluated. The samples were treated at a pressure of 10 MPa and temperatures of 32, 42 or 52 °C for 5, 10, 15, 20, 25 or 30 min. Temperature played a prominent role in the inactivation of both AB and Y&M when combined with HPCD, particularly for AB at 52 °C and Y&M at temperatures ≥42 °C. Nisin increased the susceptibility of AB to the combined treatment of HPCD and MH (HPCD + MH). A reduction of 4.19 log cycles was achieved by HPCD + MH at 52 °C for 15 min, and complete inactivation of AB was obtained by combination of HPCD, MH and nisin (HPCD + MH + nisin). No significant effect of nisin was found on the inactivation of Y&M.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacteria, Aerobic / drug effects
  • Bacteria, Aerobic / growth & development
  • Beverages / microbiology*
  • Carbon Dioxide / metabolism*
  • Colony Count, Microbial
  • Food Handling / methods
  • Food Microbiology / methods
  • Food Preservation / methods*
  • Fungi / drug effects
  • Fungi / growth & development
  • Hot Temperature*
  • Litchi / microbiology*
  • Nisin / pharmacology*
  • Pressure
  • Yeasts / drug effects
  • Yeasts / growth & development

Substances

  • Nisin
  • Carbon Dioxide