NEW YORK (PIX11) — It may not seem worth much, but used cooking oil is being referred to as liquid gold.

Suffolk County Police said they’ve seen “probably over 100 cases” countywide this year of thieves siphoning grease from restaurant storage containers in the dark of night to sell it for a profit later.

On Wednesday, police arrested 23-year-old Hector Castrol-Espinal of Queens for allegedly stealing used cooking oil on five separate occasions from the Chick-fil-A in Huntington Station.

Suffolk Deputy Chief William Scrima said, “They usually use a van with some type of barrel in the back of it. They’ll put the oil in the back of their van and take it to a reprocessing place.”

Christopher Herrmann, an Associate Professor in the Department of Law, Police Science and Criminal Justice at John Jay College of Criminal Justice, told PIX11 News the used cooking oil “can be recycled and filtered and put into biodiesel engines, so the cost of the diesel being over 5 dollars a gallon. A thirty-gallon container of oil is worth $150.”

John Musovic, the owner of Sojourn Social on the Upper East Side, has a contract with a company that pays him $50 to haul away a barrel of the grease. Still, he said people posing as the company’s workers have tried to trick him into giving it to them instead.

Musovic told PIX11 News he was approached by men who would say, “We would like to clean your grease traps, let us take your oil, and then random companies would show up, saying we’re with your company to check the oil, it was like a big mafia.”