The olive tree ( Olea europaea) is steeped in history, with humans having used it as a food for at least 5,000 years, and as a symbol of abundance and peace (branches), and purity, wisdom and fertility (fruit). Today the fruit is used to create table olives for eating, and the amazingly useful olive oil. Of additional interest is the leaf which is a valuable medicine, with anti-inflammatory, antimicrobial, anti-atherogenic, and blood pressure regulating activity.As a member of the Boundary Bend Olives Expert Scientific Steering Committee, I have been fortunate to work with some passionate experts in the field of olive science. Over the last 18 months, the Olive Wellness Institute has funded my research examining the chemical profile of different olive leaf extracts on the marketplace. Since March this year, I have been presenting the results of this research at multiple conferences, and in May they invited me to co-host two tours of the Boundary Bend olive groves, and provide invited health professionals with a summary of my research findings.The harvest tour commenced with a private plane from Sydney, straight into a small airstrip in the groves located just south of the New South Wales/Victoria border. Our 16 May trip included Dr Simon Poole, a GP and health educator from Cambridge, UK, and Dr Tassos Kyriakides, a researcher from Yale University, USA, and we all had a fascinating conversation about olives and health care on the flight down! For the 21 May trip, I was joined by fellow Endeavour academics Julie Cantwell (Senior Lecturer – Naturopathy) and Lisa Phillips (Senior Lecturer – Nutritional Medicine).Upon arrival, we were welcomed with a morning tea consisting of olive leaf tea blends, fruit and nuts, before setting off to see the harvesters in action. The harvesters are custom built and designed to emulate the traditional methods of shaking the trees to dislodge the fruit. The machines run 24 hours a day during harvest season, with the olives reaching the processing facility no more than four hours after coming off the tree.We followed the olives to the processing facility, where we got to see them being cleaned, screened, and pressed to release their wonderful oil. The smell of fresh olives was mouth-wateringly strong! True extra virgin olive oil is defined by its chemical and flavour profile, and to achieve this standard the processing must be entirely mechanical, and the attention to detail at this facility is amazing. One of my favourite examples is the machine which screens for "mummified" and rotten olives, which even in tiny amounts can ruin the flavour profile. A conveyor drops the olives in front of combined optical and infrared cameras, which sense colour and temperature changes consistent with suboptimal olives. When one of these olives was detected, we heard the hiss as a jet of compressed air knocked that olive out of the falling cascade into a reject bin!We were able to taste fresh oil coming straight out of the vertical separators. In this case, it was from the Picual varietal (one of my personal favourites!) – a robust tasting oil, rich in antioxidant and anti-inflammatory biophenols such as oleuropein and oleocanthal. It is amazing to think that earlier the same morning this oil was still fruit on the tree.After the tour, we were led through a tasting of different types of extra virgin olive oil, from the mild oil produced from the Arbequina varietal to the more robust oils from Picual and Coratina olives.At the end of this tasting, I presented a summary of my research on olive leaf extracts to the attendees. Having used olive leaf clinically in my own practice for more than 25 years, a question I have often asked is "which particular product should I be using?" To answer this for myself and other practitioners, I chemically profiled 12 different olive leaf extracts from Australia and North America. The results were interesting, showing that extracts varied enormously, meaning clinical results are not likely to be consistent between different products. It also showed clearly that extracts made from fresh leaves (as opposed to first drying the leaves) had a more favourable oleuropein level, an important constituent in olive leaf extract.Finally a lunch from Californian chef Kevin O’Connor, who served up an olive oil-themed feast on outdoor tables set in the groves, explaining to us which type of oil he used and what it contributed to the flavour of each dish. Lunch was also an amazing opportunity to connect with other researchers, clinicians and educators, and exchange knowledge and share our diverse expertise. Great food, amazing olive oil, stimulating conversation, and olive trees all around!At the end we flew off, looking behind us at more than a million olive trees, and leaving with a far greater appreciation for the wonder of the olive tree, and the effort needed to produce quality extra virgin olive oil, and olive leaf extract.