In a world-first, Industry & Investment (I&I) NSW scientists are exploring how long olive oil can be confidently stored and still taste great.

Consumers are set to benefit from the Rural Industries Research and Development Corporation funded project which aims to boost the science which predicts the shelf-life of olive oil.

I&I NSW principal research scientist, Rod Mailer, said while the tests to predict oil shelf-life exist this project is taking the chemistry a step further.

"We’re already testing oil to authenticate that it is extra virgin olive oil, now we’re looking at the factors which cause oil to oxidise and recording the reactions of a range of oils during the three-year project," Dr Mailer said.

"The chemical composition of each oil has been analysed and we are exposing them to light, temperature and oxygen   all of which cause oxidation."

Oxidation eventually produces off-flavours and bad odours in oil and the aim of the project is to identify how to extend oil stability so that the fruity olive oil flavour lasts longer.

Dr Mailer said that oils with high levels of polyphenols, which are antioxidants, and low levels of polyunsaturated fatty acids can last 18 months or two years.

"Some of these oils made from younger, early-harvest olives have a pungent, bitter flavour which is not popular with some consumers and while oils from older olives taste mellow they may have a shorter shelf-life," he said.

"The research is examining how to get the best of both worlds.

"We can take oil which is high in antioxidants with a stable fatty acid profile and blend it with less pungent, softer oil to produce a mellow, fruity-tasting oil with an increased shelf-life."

Crop management, olive variety and harvest techniques also impact on how long oil will last.

"The amount of water trees get during the growing season also affects shelf-life water-stressed trees produce more polyphenols resulting in pungent, longer-lasting oil."                                                                                              

Dr Mailer can be contacted at the Australian Oils Research Laboratory Wagga Wagga Agricultural Institute (02) 6938 1818.