Life in a Dol House
Special Edition
2017 - Week 50

Oil in a day's work

Next time you are in your local supermarket and see the rows of bottles of olive oil, spare a thought for a moment, for the donkeys which once were used in large numbers across the Mediterranean, to produce the golden oil.

I have retained the donkey hitching stone in my Dol house courtyard, although I am not planning on re-populating my stables any time soon.​

Olive oil is produced from Spain in the west, across the Mediterranean to the Levant in the east. 

It is also produced in several other parts of the world with similar climates, but the olive tree originate in the Mediterranean basin.

The Olive has been a crop and staple of the local diet for thousands of years, with archaeological finds confirming production and storage for as long as there have been people present in the region. 

As long ago as 3,000 BC, olives were being grown commercially on the Greek island that today we call Crete.

There are several hundred varieties of olive tree, producing different kinds of drupe fruit. Most are used to produce the oil, but several varieties are "table olives", which after being soaked, pitted and sometimes filled with pieces of red pepper, are served on their own or as accompaniments to wine and cheese.

Farming olives takes time 

It is an all year round job - but at this time of year, when the harvest has been gathered in, the work in the fields stops and the focus transfers to processing the fruits into oil.

In the spring, tiny green buds appear on short stems,

​they swell and each of the buds opens to a quite insignificant creamish white flowers.

Once pollinated by bees and other insects, these go on to become the fruits.

Colours vary, but they are generally green or black when ripe, however red, yellow and brown can all be found.

The trees require minimal maintenance during the year. Orchards or olive groves can be carpeted with grass, with flowers or can be bare soil.

​The trees are generally low growing - which makes picking the olives easier - and trees grow to a great age. 

The olive tree of Vouves, has been documented as one of the 12 oldest trees alive in the world today, but it is just one of seven olive trees in the Mediterranean basin that are believed to be between two and three thousand years old - and they are still producing fruit and oil.

However it is the analysis of pottery vessel fragments recently discovered in present day Israel, that shows a Bronze age community was harvesting and processing olives into oil some 8,000 years ago.

Picking is a family affair here on Hvar, with several generations involved. There are none of the mechanical harvesters found elsewhere in the major producing areas. 

Generally the drupes are pulled by hand and placed into crates. Occasionally a tarpaulin will be laid under the tree and the tree will be shaken then the fruits will be collected from the sheet. 

Sometimes a type of comb or hand rake will be used to harvest the drupes from the branches. At the same time trees are pruned back.

Throughout the summer, aided by the summer sun and deep roots, reaching into the rocks for water sources, the fruits swell. 

Then in late September they start to change colour. 

Picking on the island begins towards the end of October and gets into it's stride in November.

Once harvested, all the drupes will be placed in huge plastic vats and will be covered with water and allowed to soak for several weeks. This softens the fruit and removes some of the bitterness.

​I found some blacksmith made hoops on one of the stable roofs at my Dol house, that are 1.25 meters in diameter. 

These would have held the staves of a wooden vat in place, and of course wooden vats have been used for centuries before plastic was invented.

The water is changed once or twice, then the drupes are collected in 25kg crates, 

sluiced down and left to drain before being bagged or left overnight before being taken to be processed.

Depending upon the quantity, the farmer may use a small trailer or a truck to move the drupes to the press. 

A booking will have been made some time in advance, and a time and date will have been allocated, with the first run of the day starting at 06:00. If you have the first slot, you will have to be up early!

Today there are two processes before the oil reaches the shelves in your store. The cold process produces the extra virgin oils, but a hot process is used to produce the virgin and regular olive oil. On the island, both hot and cold processes are used, but there is none of the chemical processes, which are used commercially, to extract every last drop of oil from the waste.

From the many different varieties of olive trees come different varieties and qualities of oil. 

Different countries have bred and refined the trees which grow well in their specific soils and climate, to produce the oil that people want. 

Each variety has a distinct bouquet and flavour, a different colour and when tasted, they will excite different taste buds in the human palette.

The International Olive Council lists and defines five types of olive oil, but different countries call their oils by different names. 

The one common denominator is that Extra Virgin and Virgin oils are the highest quality, and if they are certified organic as well, then you can be assured of their quality. 

There is a lot of information available now about how to pick the right oil for your kitchen, but if you buy oil in a local market, it may be supplied in re-purposed soft drinks bottles, with little information about its provenance. 

There are some small stalls which sell artisan oils, high quality and low volume, often with their own label. 

In the supermarket you will be faced with a bewildering variety of oils and prices.

The day starts earl;y at the olive press. 

In one part of the building, which also contains the village Post Office, 100 year old machines quietly work for 1,260 hours every season. For sixteen hours a day, for seventy straight days, starting at 6am every day. 

This is a true cooperative. Work by the community, for the community.

At the start of the process, some 100 kg or more of olives are emptied into a large tank.

The shoot is opened and using an ancient blacksmith made tool, the farmer pushes his crop of olives down the shoot and under two continuously rotating 600 kg stones revolve, grinding and crushing the olives into a paste.

​Each batch spends around an hour being rolled into a slurry.

Hot water, at 120 C is mixed with the olives as they are crushed. 

Once thoroughly crushed and mixed into a brown sloppy brown paste, a second gate is opened and this slurry is part pushed by a blade between the wheels and part helped by gravity, down a second shoot into a tank with a rotating auger.

More rotating blades thoroughly mix the slurry, which gives off a not unpleasant, sweet, almost fruity scent. 

It is hard to say what it reminds me off - but I could not identify it as olive oil. 

This gentler process of mixing causes the oil in the paste to clump together and to separate from the solid material.

After some 40 minutes of mixing, workers then put a 1 1/2 cm layer of the paste onto circular wicker mats.

These are layered in fours between heavy concave circular stainless steel plates, onto a wheeled trolley.

This heavy cast iron contraption has a stainless steel central column two meters tall, perforated to allow the oil to escape. The base is a huge collecting tray shaped like a funnel with a valve where the oil and water runs out.

​Twenty four layers are put one on top of another, so 96 individual mats, until there is room for no more. 

Already oil and water can bee seen running from the lower layers, being pressed out by the weight of the upper layers. The concave shape of the steel dividers helps the oil to run to the outside, and just the sheer weight of the layers above pressing down, starts to extract the oil and water from the lower layers.

After some 30 minutes, the trolley is wheeled under a hydraulic press. It takes the combined strength of three men to move the trolley and guide it into position.

The press is then activated, a hydraulic ram lifting the trolley from underneath, compressing the layers and pressing the oil out. 

A hazy brownish yellow emulsion starts to run off the edges of the stainless steel plates, helped by more hot water.

​The oil and water emulsion is filtered through several stainless steel gauze plates and then is collected in a bottom tank.

The press reaches 380 BAR and maintains the pressure for an hour.

All the while the oily emulsion is collected.

A suction pump draws the emulsion up, mixed again with hot water.

​It is fed into a centrifuge where the oil is separated and the now pure but still cloudy yellow oil is collected into plastic containers.

The water pours down a separate shoot and into a settling tank, before being discarded.

​After an hour at sustained high pressure, the layers of matts are washed down with 120 C water, to remove the last clinging oily residues, then the trolley is lowered, the next one wheeled into place for the process to start again.

​The workers remove the layers of now dry residue, one by one, emptying them into a wheelbarrow and piling the mats up, ready for the next load. 

These have the consistency of cork and are dry and ready to burn.

An ancient water boiler is kept fed by the residue, which burns extremely hot because of it's high calorific value.

​The remainder is taken away by the farmer to be burnt in their fire at home over the winter.

​From some 1,250 kilos of olives, 270 litres of oil are produced. 

The farmer pays the cooperative for the number of pressings. In turn the cooperative pays the wages of the local men who run the press, and for the maintenance of the plant and equipment.

The substantial cast iron machinery is in its second home, having been brought up from Stari Grad in the early 1950's. 

Over time it has been modernised, but the basic machinery is around 100 years old. 

Originally the wheels were turned by donkeys and the press operated by hand.

Now although there is still a lot of human involvement, especially in the picking and handling, the heavy work of pressing is done by electric motors and hydraulic pumps.

Once separated, the oil will be stored in dark, air tight conditions and the solids in the oil will sink, leaving a clear liquid with colours from green through yellow and gold to ochre.

Early in 2018 at festivals from Japan to New York, producers will display the best of their 2017 crop. 

It will be sniffed and tasted by distinguished experts, and significant prizes will be awarded to the best vintages.

Here on the island, the oil will be bottled and used at home, in local hotels and restaurants and some will be exported. 

Next summer, small bottles will be for sale in the open markets on the island, and some will be given away to visitors who stay in farm cottages and villas.

Meanwhile, the farmers will soon be taking their rotorvators into the olive groves to prepare the soil between the trees, and so another year begins.