What was it all about?

The olive levy has supported a range of now-completed work into identifying, testing and removing potential impurities in Australian olive oil. These have included:

• Investigating olive oil quality improvement through filtration (OL16007), a short project that looked at the availability of technically and financially feasible options for removing any impurities that may be present in olive oil, including but not limited to filtration approaches. The project revealed a number of avenues suitable for further investigation, including the use diatomaceous earth as an adsorbent, the use of ‘ultrasonication’, and the effects of carbon-based adsorbents on olive oil composition and traits.
  
  
• Processing water treatment options to improve olive oil quality (OL16008), another short project that looked at processes that can be used to remove or reduce levels of any impurities that may be present in water used for olive oil processing.
  
  
• Olive industry pre-harvest water and oil quality testing (OL16005).
  
  
• Olive industry fruit, oil and water quality testing – phase 2 (OL17005), which was a project that continued industry research into possible impurities in olive oil products. The researchers explored potential impurity entry points, from on-farm treatments of olive fruit, to the water used in spraying and the equipment and steps in the processing of fruit and oil. The work didn’t find a clear single source of potential impurities, but pointed to the potential for accumulation of impurities across the entire growing to processing and packaging process (though the oils the project team sampled did not show impurities above acceptable levels). Recommendations for growers and processes from this work include:
  
  
  • Thoroughly cleaning and maintaining systems supplying water to the plant
  • Analysing water sources to check they are free from potential impurities
  • Monitoring levels in fruit throughout the growing season.

For more information on this research, olive growers and processors are encouraged to contact Hort Innovation at communications@horticulture.com.au.