A plain clothes police officer stops a vendor on the Barceloneta beach on Wednesday. Massimiliano Minocri

In the mojitos, for example, there was an E. Coli count of 720, a figure which, according to European regulations should be under 10, while some sandwiches had a count of 6,000 – a level which should legally not be above 1,000.

Meanwhile, down at the beach, little has changed, despite intense media coverage. The hawkers continued to play cat and mouse among the towels and parasols with the 90 officers assigned to Barcelona’s beaches on Wednesday.

Meanwhile, down at the beach, little has changed, despite intense media coverage

One group of men was mixing drinks on the beach before they were interrupted. “This is where they make their mojitos,” said one officer, pointing to the plastic glasses, ice, mint and bottles of rum and lemonade left behind on the sand. Along with the 7,217 reports filed during June and July, authorities have seized as many as 133,622 drinks, according to City Hall, 20% up on last year.

“These guys know that their clients are the millions of foreigners that come to the city,” says an officer on the Barceloneta beach. Nearby, a plain-clothed policewoman stopped a young Pakistani man bearing a tray of lurid green drinks. “Come with me,” she tells him and, away from the crowds, she proceeds to empty the cups and the contents of a bottle of rum onto the sand before filing her report.

It wasn’t the policewoman’s first catch of the day. Several hours earlier, she had fined another hawker, though as she admits, the fine is little more than a formality.

The young man she has just stopped, for example, admits that he has around four to five run-ins with the police a day. Now, he is waiting for this latest encounter to be over so he can return to the waterfront with a fresh tray of drinks.

If we seize the money they have made during the day, that really gets to them Plain clothes police officer

According to City Hall, in June and July, police officers were able to seize €10,151 from the hawkers, 44% up on last year. But police sources say it is a tiny slice of the illegal beach economy.

The same sources explain that hawkers carry as little money as possible on them. As soon as they make a sale, they take the money to a colleague whose sole purpose is to guard the cash. “They know they will be stopped,” says the spokesman. “They get annoyed when we bin their products, but if we seize the money they have made during the day, that really gets to them.”

Other unlicensed vendors sell sarongs, give massages and braid hair. Once these activities are included, the number of reports filed by the police in June and July rises to 12,721, compared to 11,547 last year.

Samuel Portaña, head of food safety at Barcelona’s Agency for Public Health, says the problem with unlicensed vendors is that no checks are made on the environment in which the food is prepared, noting that fairground stalls are subject to inspections from the authorities.