Operators have been advised to keep used cooking oil secure after two men were jailed for thefts from restaurants and supermarkets.
The two men jailed this week had been posing as contractors to steal the oil, which would then be turned into biofuel.
Stuart Bradley and Matthew Walker stole 220,000 litres from takeaways, restaurants and supermarkets including KFC and Tesco. They admitted conspiracy to steal and were each jailed for two years.
As a renewable energy resource, used cooking oil now commands a high price, but according to oil recycling firm Agri it is rarely stored safely. It estimates that 20% of the UK's used cooking oil is stolen, thought to be worth £50m.
Gavin Millar, group systems and procedures manager, at Agri said the case highlighted what is a growing problem for restaurateurs.
He added: "There is a substantial black market around the theft of used cooking oil. This is not a crime without direct harm to people and businesses. The increasing scale of the problem in the UK directly deprives people of job prospects and security. The illegal production of biodiesel can be highly dangerous to human life and to property. Businesses need to be aware of the value of their UCO and take the right steps to protect it from thieves."
The firm advises that operators keep used cooking oil in a secure area and ensure staff know who is supposed to be collecting it by asking for ID.
By James Stagg
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