Organised gangs are becoming increasingly sophisticated in their use of technology to perpetrate widespread food fraud, according to experts.

A rise in criminal targeting of the food and drink sector is being blamed on the huge mark-ups that can be made by passing off inferior products as premium goods, coupled with the fact that there is little oversight and lenient penalties for those caught.

Concerns about the role organised crime is playing in the endemic diluting of virgin olive oil has seen the UK government appoint a specialist testing company to establish if the grade declared on the label is genuine. Olive oil is recognised by the EU committee on the environment, public health and food safety as the product most at risk of fraud by gangs, in particular Italian crime syndicates. Other foods attracting the interest of organised crime, according to the committee, include fish, milk, honey and rare spices such as saffron.

The committee has warned that it "is concerned about signals indicating that the number of cases is rising and that food fraud is a growing trend reflecting a structural weakness within the food chain." In a draft report, it claims that "recent food fraud cases have exposed different types of food fraud, such as replacing key ingredients with cheaper alternatives, wrongly labelling the animal species used in a meat product, incorrectly labelling weight, selling ordinary foods as organic, unfairly using origin or animal welfare quality logos, labelling aquaculture fish as wild, counterfeiting and marketing food past its use-by date."

Hilary Ross, a lawyer who specialises in food security issues and has contributed to the government's forthcoming Elliot review into the integrity of the UK's food chains, produced in response to the horsemeat scandal, said that the nature of the threat posed by criminal gangs to the food chain was changing.

"In terms of criminal activity they are becoming ingenious," she said. "If one thing is detected they move on to another. But there is not one magical science cure that tests for everything. You have to know what you are looking for."

Stuart Shotton, a former trading standards officer whose company, Foodchain Europe, advises clients on food security, said the baby milk scandal in China had shown that criminals were increasingly clever in their use of technology to deceive regulators.

"A lot of Chinese infants ended up seriously ill and died," he said. "When you look at the science behind it, someone was clever enough to work out that the way they test to ensure milk is the right quality is through the protein content. Then they figured out that the way protein is measured is by looking at the amount of nitrogen produced, and then figured out that melamine is an excellent source of nitrogen. This is not happening by chance. Someone's actually thought about it."

Shotton pointed out that a recent global crackdown on organised criminal gangs perpetrating food fraud, Operation Opson III, had uncovered tens of thousands of fake chocolate bars: "This shows that they are moving beyond just substitution – changing one element of a food. It's making something look like something else altogether."

Experts say the new threats posed by criminal gangs meant regulators needed to change their game.

"We have to think like a criminal," said Jenny Morris, principal policy officer at the Chartered Institute for Environmental Health. "If you know a crook is going to be looking for opportunities to make maximum money, then you have to look where that might be." She warned that a failure to act could have serious health consequences.