Microbiological Quality of Bagged Cut Spinach and Lettuce Mixes

Abstract

Analysis of 100 bagged lettuce and spinach samples showed mean total bacterial counts of 7.0 log 10 CFU/g and a broad range of <4 to 8.3 log 10 CFU/g. Most probable numbers (MPN) of >11,000 /g coliforms were found in 55 samples, and generic Escherichia coli bacteria were detected in 16 samples, but no E. coli count exceeded 10 MPN/g.

Microbiological quality of fresh vegetables and fruits sold in Singapore

“…The mean aerobic bacterial count of fresh-cut salad obtained in this study was similar with that of a recent study conducted under Food and Drug Administration (FDA) in the United States (US), where 100 bagged lettuce and spinach mixes were sampled. The mean total plate count was around 7.0 log cfu/g, with a range of <4e8.3 log cfu/g (ValentinBon, Jacobson, Monday, & Feng, 2008). Similarly, a study in the US conducted by Hagenmaier and Baker (1998) reported that 52 bagged salads were found to have a mean total plate count of 7.0 log cfu/g.…”

Escherichia coli Common Pilus (ECP) Targets Arabinosyl Residues in Plant Cell Walls to Mediate Adhesion to Fresh Produce Plants

“…coli O157:H7, one of the most important causative agents of fresh produce-associated outbreaks, is often linked with contaminated lettuce and spinach (11,12).…”

Microbial ecology of fresh vegetables

“…Vapor condensation could also lead to the accumulation of water inside the bags. Valentin-Bon et al (2008) sug gested that moisture (i.e., condensation) observed at the bottom of many bags may pro vide a better opportunity for microbial growth including that of any pathogens present. In a subsequent study, Kase et al (2012) noted an absence of moisture condensation in the bags, which may suggest industry advances in mois ture control and bag design (e.g., anti-fog film, perforated versus non-perforated, etc.…”