Food-grade avocado oil is increasingly making its mark on international shelves. South Africa’s Da Gama Oil is the world’s largest, and a pioneer producer of, edible avocado oil. Da Gama’s CEO, Koos de la Rey, says avocado oil has only become well known on the world food market during the past two years. But he says it will always be a niche product that will never be able to compete with other edible oils in price, availability or popularity.
"I do foresee, however, that its popularity, due to its fantastic quality, will eventually outstrip its availability," he says.
But this does not mean that any grower with an orchard can start producing his/her own edible oil, as olive oil producers do.
De la Rey says the high quality of food-grade oil that is demanded on world markets requires centrifugal extraction and batch refining in state-of-the-art capital-intensive equipment that is custom-made.
Only ripe, but not over-ripe, fruit is used. In the first stage of the process the fruit is crushed, preheated and pumped into centrifuges, where oil is extracted.
The oil is then subjected to the refining process, in which it is degummed, neutralised, bleached and filtered to ensure removal of all impurities. The oil is then winterised at 4°C to ensure stability under colder temperatures, and the winterised crystals are filtered out. The next step is to deodorise the oil, ensuring minimal peroxide levels. Thereafter, the oil is cooled and drummed.
Finally, the oil is analysed by independent laboratories to ensure that it conforms to the strictest specifications; this includes a 24-hour cold test. The oil is finally despatched to international clients in drums and bulk tankers, preserved with nitrogen.They repackage and market it.
There are, however, options for small to medium-sized avocado oil producers, as the oil can also be extracted through pressing. Small units costing about $20,000 are capable of pressing up to 2t/day of fruit. These presses would have to be adapted to crushing dried avocado – the cost of drying the fruit, which has to be done thoroughly, is a factor to be considered.
Furthermore, the product is only suitable for cosmetic and medicinal purposes because of the unacceptable taste, smell and colour, which is imparted during the drying process.
Also its vitamin content is destroyed in the process – though called "cold" pressing, it involves heat exceeding 100°C.
An option for medium-sized growers or co-operatives wishing to produce edible oil is to extract the oil centrifugally, then sell it to refiners.
There are, for example, three medium-sized processors in Kenya. One of them recently invested around R23m in centrifuges to do extraction for groups of small growers. The oil will be sold either to South Africa or to a refiner in the Netherlands.
De la Rey says almost all edible avocado oil on the world’s markets currently originates from South Africa, though small quantities of edible oil are now also produced in Australia and New Zealand.
The larger avocado growers of Mexico and Brazil generally produce (inedible) pressed oil.
It is generally accepted that an avocado fruit produces around 10% of its weight in oil. An orchard of one hectare can carry up to 550 trees, which can bear around 5t fruit per year, to produce 500kg of oil.
GEA Westfalia Separator SA: Tel 011-805-6910; firstname.lastname@example.org ;
Barry Hannah, Olive & Wine Specialists: Tel 083-357-5007.