Survival of Cronobacter species in reconstituted herbal infant teas and their sensitivity to bovine lactoferrin

J Food Sci. 2009 Nov-Dec;74(9):M479-84. doi: 10.1111/j.1750-3841.2009.01371.x.

Abstract

Cronobacter is a new genus containing 5 species previously known as Enterobacter sakazakii. The popularity of "natural" substances and alternative medicine has extended the use of natural antimicrobials and herbs to foods, and some herbs are claimed to relieve gastric disturbances in infants. The present study investigated the antimicrobial activity of bovine lactoferrin (LF) and Cronobacter survival in commercial herbal infant teas (HITs) reconstituted with water at different temperatures. Cronobacter cells were able to grow in all reconstituted HITs at 37 or 21 degrees C after 6 h. A 4-log reduction in Cronobacter was achieved by reconstituting herbal infant tea at > or = 60 degrees C. LF was able to reduce Cronobacter species viability in herbal infant tea. No viable cells were recovered after 4 h at 37 degrees C in the presence of > or = 5 mg LF/mL. The bactericidal activity of LF was reduced at lower concentrations and lower temperatures. This study demonstrates that if present in reconstituted herbal infant tea, Cronobacter can grow and this may compromise the safety of these products. Therefore, addition of LF to reconstituted HIT may be a promising approach for the effective control of this organism. Practical Application: Cronobacter species can be isolated from herbal teas, and these products are claimed to relieve gastric disturbances in infants. This study demonstrates that Cronobacter cells present in reconstituted herbal infant teas (HITs) can grow if not held at acceptable temperatures. It was shown that reconstitution of these tea formulas with > or = 60 degrees C water reduced the potential risk from Cronobacter. Furthermore, use of lactoferrin (LF) may be a promising approach for effective control of these organisms in HIT held at nonrefrigeration temperatures (10 to 37 degrees C) for short periods.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-Bacterial Agents / pharmacology*
  • Beverages / analysis
  • Beverages / microbiology*
  • Calcium, Dietary / analysis
  • Colony Count, Microbial
  • Cronobacter sakazakii / drug effects*
  • Cronobacter sakazakii / growth & development*
  • Food Microbiology*
  • Food Preservatives / pharmacology
  • Foodborne Diseases / prevention & control
  • Hot Temperature
  • Humans
  • Infant
  • Infant Food / analysis
  • Infant Food / microbiology*
  • Iron, Dietary / analysis
  • Lactoferrin / pharmacology*
  • Magnesium / analysis
  • Microbial Viability / drug effects
  • Milk Proteins / pharmacology
  • Osmolar Concentration
  • Phytotherapy
  • Time Factors

Substances

  • Anti-Bacterial Agents
  • Calcium, Dietary
  • Food Preservatives
  • Iron, Dietary
  • Milk Proteins
  • Lactoferrin
  • Magnesium