Directed Research
Potential Sources of Microbial Contamination in Unpasteurized Apple Cider

Introduction

Unpasteurized apple cider was historically considered to be a safe product, free from microbial pathogens due to its high acidity. However, in the last two decades unpasteurized apple cider has been associated with several outbreaks of foodborne illness.

Objectives

This study was conducted to identify possible sources of microbial contamination and to assess the effect of good cleaning and sanitation practices on microbial quality and safety of unpasteurized apple cider.

Methodology

Raw unwashed apples, washed apples, cleaning water, fresh cider and finished cider samples were collected from five Ontario producers over four months and microbiologically tested.

Summary of Research Results

• The washing step was identified as a potential source of contamination possibly due to water in the dump tanks seldom being refreshed, and because scrubbers, spray nozzles and conveyors were not properly cleaned and sanitized
  
• Higher (p<0.0001) total coliforms counts and prevalence in fresh cider compared to both unwashed apples and washed apples indicated considerable microbial build-up along the process
  
• Results showed that producers with better sanitary practices in place had lower (p<0.001) total coliforms prevalence than the rest of the producers.
  
• Overall results show that good sanitation procedures are associated with improved microbial quality of fresh cider, in terms of total coliforms, and that operators who pasteurize and/or UV-treat their product should still be required to have a sound Good Manufacturing Practices Program in place to prevent recontamination.

For technical inquiries:
Toll Free: 1-888-466-2372, extension 64535
Local: 519-826-4535
Email: robert.blenkinsop@ontario.ca