This is a final research report from Hort Innovation’s historical archives. Please note that as these reports may date back as far as the 1990s, the content and recommendations within them may be superseded by more recent research.

What was it all about?

Fruit quality and handling conditions varying considerably between consignments of melons was one of the key findings from the project “Improving melon supply chain handling systems”. The aim of the project was to investigate the impact of handling practices at the time and conditions from harvest to retail sale on melon quality. The project was funded by five melon businesses, Australian Melon Association, Horticulture Australia Ltd and the Queensland Department of Primary Industries and Fisheries.

Consignments of rockmelons and seedless watermelons were monitored from production districts throughout Australia to retail or processing warehouses in Brisbane, Sydney and Bairnsdale in Victoria. The monitoring involved observing and documenting handling practices and monitoring fruit and air temperatures in cartons and bins. Quality was assessed for fruit sampled from cartons and bins at the time of packing and at the destination point.

The monitoring found that each consignment had a different temperature profile and fruit may have been exposed to both high and low temperatures. The external appearance of rockmelons deteriorated before any loss of internal quality while the reverse occurred with seedless watermelons. Sunken, discoloured areas and rots start to appear on rockmelons after 2 to 5 days at 20°C. For seedless watermelons, the symptoms of quality loss were floury texture and orange flesh colour.

Simulations trials were undertaken to investigate the impact of handling conditions and practices on melon quality. Damage to the netting of rockmelons during harvesting, grading and packing increased the incidence of skin deterioration at the other end of the supply chain. Holding seedless watermelons at 30°C for longer than 3 days reduced saleable life but fluctuations in temperature between 30°C and 12°C did not affect quality.

Quality guides for rockmelons and watermelons were produced to provide a common language to describe and assess melon quality and to improve communication about quality between members of the supply chain – from seed companies through to retailers.

A survey of project collaborators and non-collaborators found that most respondents (74 per cent) had made changes or planned to make changes to the way they handle melons. Common changes were improving the harvesting system to minimise net damage of rockmelons, increased monitoring of watermelon temperatures to decide when to shift from non-refrigerated to refrigerated transport and using the melon quality guides to improve communication.