What was it all about?

The best quality dried grapes are plump, golden and uniform throughout the batch. Light coloured fruit is worth significantly more than dark fruit, so the colour grade of fruit directly affects how much the grower is paid. Currently, experienced assessors grade dried grapes using defined criteria, but there is an element of subjectivity to the process.

In 2016, this project developed and tested a number of different methods for objectively measuring the colour of dried grapes.

One emerged as the most viable: capturing images of a bin sample using a simple office flatbed scanner, then analysing the images and determining a grade based on colour using a software program. This proved to be quick, cheap, easy for operators and consistently reliable.

Tests at Sunbeam’s facility in Red Cliffs, Victoria, supported the system’s usability and showed that the standard light source within the scanner allowed reliable assessment.