Escherichia coli O157:H7 SURVIVAL IN TRADITIONAL AND LOW LACTOSE YOGURT DURING FERMENTATION AND COOLING PERIODS

Authors

  • Camila Sampaio Cutrim Universidade Federal Fluminense
  • Raphael Ferreira de Barros
  • Robson Maia Franco
  • Marco Antonio Sloboda Cortez

DOI:

https://doi.org/10.1590/cab18039554

Keywords:

Food Technology

Abstract

The purpose of this study was to evaluate the behavior of E. coli O157:H7 during lactose hydrolysis and fermentation of traditional and low lactose yogurt. It also aimed to verify E. coli O157:H7 survival after 12 h of storage at 4 °C ±1 °C. Two different types of yogurts were prepared, two with whole milk and two with pre-hydrolyzed whole milk; in both groups one yogurt was inoculated with E. coliO157:H7 and the other one was not inoculated. The survival of E. coli and pH of yogurt were determined during fermentation and after 12-h refrigeration. The results showed that E. coli O157:H7 was able to grow during the fermentation period (from 4.34 log CFU.mL-1 to 6.13 log CFU.mL-1 in traditional yogurt and 4.34 log CFU.mL-1 to 6.16 log CFU.mL-1 in low lactose yogurt). The samples with E. coli O157:H7 showed gas formation and syneresis. Thus, E. coli O157:H7 was able to survive and grow during fermentation of traditional and low lactose yogurts affecting the manufacture technology. Moreover, milk contamination by E. coli before LAB addition reduces the growth of L. bulgaricus and S. thermophilus especially when associated with reduction of lactose content
Keywords: ?-galactosidase; EHEC; fermented milk; lactic acid bacteria; lactose hydrolysis.

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Published

2017-07-31

How to Cite

CUTRIM, C. S.; DE BARROS, R. F.; FRANCO, R. M.; CORTEZ, M. A. S. Escherichia coli O157:H7 SURVIVAL IN TRADITIONAL AND LOW LACTOSE YOGURT DURING FERMENTATION AND COOLING PERIODS. Brazilian Animal Science/ Ciência Animal Brasileira, Goiânia, v. 18, 2017. DOI: 10.1590/cab18039554. Disponível em: https://revistas.ufg.br/vet/article/view/e-39554. Acesso em: 17 jul. 2024.

Issue

Section

CIÊNCIA E TECNOLOGIA DE ALIMENTOS