Mangoes Made in Australia

Abstract

Australian food products have a reputation for exceptional quality and are valued for by consumers for high safety standards. Recently, there have been several high profile incidents where Australian products “made from local and imported ingredients” have resulted in negative health outcomes which were traced back to produce that was not locally sourced. Local processing company Tropico Fruits produces an extensive range of fruit based products and list an Australian Kensington Pride mango puree among their flagship products. In light of the recent health issues arising from composite products using imported ingredients, the ability to test a processed product and identify the country of origin of it constituents is of great value to commercial enterprises that promote their products as locally sourced. Processed mango products are great candidates for assessing the feasibility of applying DNA-based identification methodologies for a number of reasons. DNA profiles have been determined for over 300 mango accession sourced from around the globe, including all the major domestic and overseas commercial varieties. Within all the commercial varieties, unique combinations of DNA markers exist such that a specific DNA profile can be traced back to the source variety. This means that even in composite purees, the major constituent varieties would be detected. To this end, four commercially produced mango purees were provided by Tropico Fruits and samples were subjected to a number of DNA extraction methodologies. While several of the methods produced workable quantities of highly degraded DNA, none of the extracted samples produced any results in the DNA fingerprinting steps. The objective of this project was to produce a set of reliable protocols that could determine the constituents of a processed product on the basis of a DNA profile. Unfortunately, while DNA was isolated using several techniques, the level of DNA degradation arising from the pureeing and sterilisation processes meant that DNA profiles could not be generated