The Polygyros olive oil cooperative does not seem a likely target for a heist. If anything, its setting, at the foot of the Holomontas mountain in Halkidiki, evokes the bucolic innocence of rural Greece. Certainly its breezeblock warehouses bear little resemblance to the modern premises that house the Mitseas olive mills in southern Messinia. But in recent weeks both have been targeted by thieves, who gained entry through a battered iron door in Polygyros and a hi-tech security portal in Messinia. “The oil has gone,” said Yannis Keliafanos, a farmer at the cooperative. “There is very little of it left.” With at least 37 tonnes thought to have disappeared from the cooperative’s storage facilities, and more than 100kg believed to have been taken from plastic barrels in Messinia, the raids have cast a new light on Homer’s enduring description of olive oil as liquid gold. “We’re talking about very big business,” said Manolis Yiannoulis, the head of EDOE, Greece’s olive oil industry association. “Thirty-seven tonnes in today’s market would be worth more than €300,000. When olive oil prices in the last year have increased by 200% because of low yields, there is a lot of money to be had.” From the Peloponnesian peninsula – famous for its purple Kalamata olives – to mountain villages in Crete, thefts of oil have proliferated. Yiannoulis, whose organisation represents every sector of the industry, from packers to producers, believes record prices for an ingredient that has long been a staple of the Mediterranean diet, but has increasingly been in short supply, have undoubtedly played a role. A large proportion of Greece’s workforce earns less than €1,000 (£870) a month, well below other EU member states. With the cost of living crisis hitting hard, the prospect of valuable oil has not only spurred thieves to break into remote village homes but raid graveyards – where, traditionally, stockpiles are kept by clerics for use in vigil lamps. “They don’t go for jewellery any more, they go for olive oil,” said Themis Kanellopoulos, a reporter based in Kalamata. “In upper Messinia there have been cases of houses being broken into with thieves only interested in storage areas, and for the first time we have seen olive oil stolen from cemeteries.” The prospect of another poor harvest has not eased the situation. Last week, Yiannis Iliadis, a producer in the region, said: “Olive mills have taken security measures, but our worry is it will be the trees themselves that are targeted next. There have been instances of fruit being stolen from orchards at night.” Greece is the world’s third biggest producer of “liquid gold” after Spain and Italy, although by proportion it produces unrivalled amounts of high-quality extra virgin olive oil: 82% of its annual 300,000-tonne output. As in Spain, it is climate breakdown that has intensified fears of severe shortages of olive oil, with growers speaking of groves experiencing a winter of very little rain before being hit by temperatures that this summer surpassed 47C. “We’re looking at Greek production rates being cut by half this year,” said Yiannoulis. “The imbalance in demand and supply is behind the very big price increases, which producers are enjoying but which are very much hurting consumers.” This reality is already being reflected at supermarkets. In the past year, domestic consumption of an ingredient no Greek would have previously done without has dropped by an unprecedented 30%, with many turning to less pricey alternatives such as sunflower oil. “Our biggest fear is the decline we have seen in Greece,” said Giorgos Oikonomou, director general of Sevitel, the Athens-based Association of Greek Olive Oil Standardization Industries. “People are opting for seed oils because they are one-third of the price. Then there is the hesitation of countries like Britain, which are now thinking twice about importing [our] olive oils because of soaring costs.” But the spate of thefts is a small matter next to the climate problems farmers will inevitably have to deal with, said Oikonomou, with global heating in the Mediterranean basin set to accelerate 20% faster than any other region. “People here will have to start thinking seriously of transferring olive groves further north to places like Thrace and Macedonia that are cooler,” he said. “We have been cultivating olives in Greece for 4,000 years and what we are seeing now is truly unprecedented.”