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Friday, November 12, 2010

Totally unprofessional olive mill repost

It is shameful to do this, but time is short. So, this is a repost. It is my repost but a repost all the same. We harvested a little over a ton of Tuscan blend olives today. The Arbequinas are about 2 weeks out. Did not get any cool pictures or glam shots. So, in the interest of olive season, we present "A trip to the olive mill, 2008":

The story of the olive goes back a few years, about 6,000. From Phoenicians to Athena to your favorite earth-toned Tuscan Villa (that actually bought theirs from Spain), the olive is a classic, kind of like Bottle Caps. Fast forward to the golden age of Kelseyville, Ca., and take a (very) brief trip through the processing of our 885 pounds of olives by Father Emilio Rafael.

Step 1. Dump picked olives into hopper, where a conveyor takes them through a brief fan-driven leaf remover and a very quick rinsing cycle. The water will centrifuge off, so that is not a problem. Then they enter:

The hammer mill that grinds them up, seeds and all, into an emulsified paste that will be worked for about 45 minutes, until the emulsion starts to break down and the water and oil start to separate, sort of like when your Bearnaise dehydrates or gets too cool or hot. This allows full oil release from the solids. It then will be pumped to the:

Horizontal centrifuge (notice the 2" hose full of olive paste coming in on the lower left of the picture). Spinning at 45,000 rpm this gives a rough separation of the solid matter, the oil, and the watery components that are pumped out through the screen in the middle of the picture. The partially processed oil is then moved to a final centrifuge

moving at 55,000 rpm that gives a final separation of oil from water and a final particulate removal down one micron! Here the beautifully green stuff trickles clean as a whistle into a receptacle that is far too large for the tiny crop. Actually, the oil still needs to settle for a couple of months. Like wine organic solids and components have just been altered, beaten, and traumatized. They they need to do their chemical dance of oxidation, precipitation, and general new life cycle type stuff. Out of the horizontal centrifuge burps the watery paste that remains after extraction, kind of an almondy smelling gross but kind of appealing gray sludge without a trace of olive oil essence.

Olives are slow work. In four days of picking we managed a lowly 885 pounds, yielding a grand 13.2 gallons of oil. Like Nick says, you can imagine in the old days that parents were always yelling at their children to turn off the damn oil lamps whenever they left the room. And a final picture of all three machines together, processing left to right.

Well, there youy have it. Of course yield should be three tons this year (we hope) which is hopefully in the 90-100 gallon range. The oil can actually vary quite a it depending on the growing conditions of the year, harvest time, potential insect damage (olive fly is always a concern) and other agricultural vagaries.

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