Would you like to know how to make olive oil ? well start with an olive tree that produces an olive with a high percentage of oil.In the last decade the trees used for high density orchards such as Arbequina, or Arbosona is a good place to start,if you are trying to grow commercially.
Or maybe a Tuscan or more traditional tree like Lucca, maybe right for you back yard landscaping and you would get olives to process for your time spent.
After the trees mature and produce olives, harvest either by machine or by hand. Here is where we start effecting the oil to be made.Olives start fermenting as soon as they are picked.So best to get the olives to the mill within eight hours.also, do not use a grape harvesting bin they stack the olives to high, we don't want the olives in bins higher than 12 inches.
Clean the olives with with fresh water,removing twigs,leaves and dirt.At a commercial mill this will be done by machine, or the hobbyist can use a 5 gallon plastic bucket with holes drilled in it to rinse the olives.
Next we crush the olives, pit and all. The olives are either crushed in a stone press,hobby mill or in the grinder of a commercial mill.Always avoid heating the crushed paste,this would effect the flavor of the oil.
Now we need to press the olive paste.The press starts the water separation process, and this is were we get "olive pumice" it is a by product of the press.we are separating the oil and water from the fruit.
We now have oil and water mixed together, we need to separate the oil from the water.A hobbyist might just let the oil and water naturally sit and settle in a container .
And the commercial mill will use a decanter or centrifugal separator,discharging the water and capturing the oil in a drum.
Finally the oil is bottled, remember that light , heat and oxygen will damage the oil.The oil should keep between 12 to 24 months before starting to go rancid.