Olive oil grading

One of the fascinating things about olive oil production in a co-operative is the paperwork and numbers involved.

Let’s take an example which relates to the olive oil press in Mairena, Alpujarras. This is a co-operative so basically operates with smallholders from in and around the village picking their own olives and bringing them to the mill where all the olives from the members are pressed together to produce what is essentially a village olive oil.

If life were simple,  Juan brings in 100kg of olives and Francisco brings in 150kg. We’ll allocate 40% of the oil to Juan and 60% to Francisco. The guy running the mill takes a percentage of the sale price in return for turning those olives into oil. That would be fairly simple.

Now turn two producers into a hundred. Then add in 75 days of harvest so Juan brings in 100kg one day but 40kg the following weekend and 200kg the Tuesday after that.

Add to this the fact that each grove and batch tends to have a different yield so Juan’s olives might only deliver 24% oil whereas Francisco’s deliver a whopping 29%. Though olives from different trees within a smallholding will deliver differently – age of tree is a major factor for instance.

Each delivery from each member has a sample taken from it to measure yield.  On the day I visited the olive oil press in Mairena, the yields varied from 26.69% to 29.83%. Yep, let’s throw in a couple of decimal places!

Then you have the acidity. Olive oil is graded by acidity – it can only be extra virgin if it’s below 0.8% acidity so each batch delivered by each farmer has to be sampled and tested for both yield and for acidity. The overall average acidity is that which can be assigned to the finished, collectively produced, product.

What you end up with is a remarkably complex set of data which ensures a fair distribution of the oil. What makes it all the more lovely is that the pressing and production and all of the data is managed by Adolfo, the local taxi driver.