Phyllis Phua

• Bsc (Honours) Food & Human Nutrition (Newcastle University Singapore)
• A Comparison of Microbial Contamination Susceptibility in Organic and Conventional Lettuce

Microbial contamination is a concern to food safety. This is especially in raw foods such as lettuce, a common ingredient in salads. Organic vegetables are gaining popularity as a healthier option compared to conventionally grown vegetables. Yet there is limited information known about their susceptibility to microbial spoilage. This study compared spoilage due to microbial growth between organic and conventional iceberg lettuce.  Samples were swabbed and the resulting bacterial colonies were identified using different biochemical tests. All bacteria identified were non-pathogenic. The number of bacterial species grown were characterised, and no significant difference was observed in the number of different bacterial species grown on the lettuce from the different sources. The lettuce samples were stored in the fridge to monitor decay. Organic lettuce decayed about one week earlier than conventional lettuce. This could be due to the relatively chemical-free soil composition of organic vegetables.

 Funding source: Newcastle University

Supervisor: Dr Saloni Kaur Dang