Olive crops are poor this year, and some folks may not harvest them at all. They may not fruit due to factors such as insufficient sunlight, inadequate pollination, pruning mistakes, and nutrient deficiencies, but due to an off-year in the olive trees’ natural alternate bearing cycle, together with this year being difficult because of drought and high temperatures at the flowering time, the crops are not good. Mine are poor, thin and shrivelled, very few are full fruit. Maybe this year is not a good one for anybody – and the price of olive oil is consequently expected to rise.
Olives contain a bitter compound called oleuropein. Olives must be ‘cured’ to remove that bitterness in order to make them palatable, and the easiest and commonest curing processes for home use is brine – have a go, if you are lucky enough to have some olives this year.
The earlier you harvest, the more bitter the taste. All olives start off green and can be harvested then, or when fully ripened to black, or any stage in between. Most olives are ready to harvest when the juice turns cloudy, at the ‘green ripe’ stage in late September, and finally darken to the ‘naturally black ripe’ stage by early December. Olives in this stage have a high oil content and are easily bruised.
Why are olives pressed three times for their oil?
The first pressing produces the purest oil. In Biblical times, this was used to fuel the lamps in the temples, for anointing, and for meal offerings. The oil of the second pressing was used for medicinal purposes, and the third press produced oil used for soap.
Olives picked in October are typically ready to eat in the following May or June. Shelf life may be relatively short - one year or less.
The simplest for the novice is brine-curing, and this is how.
Cure Olives in Salt Brine
The process for curing olives takes patience but the effort involved is not difficult. Start by picking your olives. Choose the darkest, fattest olives that are unblemished. You can make a simple brine solution using a ratio of 1 part salt to 10 parts water, using an unprocessed salt such as rock or sea salt.
If you squeeze one, it should release a milky liquid if it's ready to brine. Slitting each olive will allow the water and salt to penetrate it faster and remove the bitterness, or you can carefully 'crush' your olives with a heavy object such as a meat tenderiser. Crush them enough to just break the skin but not to completely flatten them. If you leave them whole, they'll need to sit in a brine a lot longer, and if you have a real difference in colours, you can soak the greener ones away from the black ones, as the green ones are less mature and will need longer in brine.
Cover them with the brine and make sure they are completely submerged, and loosely seal your container. You may need to loosen or open it every couple of days for the first week to release some of the gases. If the olives stay submerged and there is no sign of mould, the brine doesn't need to be changed. If mould is growing, tip the brine out, rinse the olives really well and make fresh brine, but changing the brine weekly will leach out the bitterness faster. Taste them after a month or so, and keep soaking them until you are happy with the taste.
Olives are an excellent source of monounsaturated fats - which are considered heart-healthy fats - and can help lower bad cholesterol levels when consumed as part of a balanced diet.
If you're planning on pressing your own oil, you'll usually need 36-45 kg. of olives to make 3.8 litres of olive oil, but if you want to, I am told you can take your own to a commercial processor and they will repay you with bottles or jars of oil.
But cure your own – then add your own choice of flavouring yourself!
Marilyn writes regularly for The Portugal News, and has lived in the Algarve for some years. A dog-lover, she has lived in Ireland, UK, Bermuda and the Isle of Man.