Food Unwrapped, C4, 8.30pm
JIMMY Doherty is on a mission to find out why jelly won’t set if you add chopped papaya to it. He could probably find out the answer in a kitchen or a laboratory in the UK, but as this series is nothing if not thorough, he heads to South Africa, where he discovers that it’s all to do with the fruit’s enzymes, which can be used to tenderise meat. But could they also help the human gut? Meanwhile, Kate Quilton is in Hawaii for a tuna auction to learn why some fish have dangerous levels of mercury and others don’t, before she heads to San Francisco to meets the people who are growing fish flesh in a dish. Finally, Matt Tebbutt asks why the ice cubes made in the freezer at home are usually cloudy while the shop-bought versions are clear.

Today at Wimbledon, BBC2, 8.30pm
CLARE Balding presents highlights of the opening day’s play at the All England Club, where the first round got under way in the men’s and ladies’ singles. Much of the attention will have been on the opening match on Centre Court, which saw Roger Federer begin the defence of his title, as he aims to triumph for an astonishing ninth time at SW19. The bottom half of the women’s draw also started, as the players looked to emulate 2017 champion Garbine Muguruza of Spain, who defeated veteran American Venus Williams in last year’s showpiece.

Versailles, BBC2, 9.30pm
MADAME de Maintenon is welcomed back to Versailles as a permanent member of King Louis’ council, shedding her moderate attitude to Protestants, while the queen’s erratic behaviour places further strain on her relationship with the king.

Inside the American Embassy, C4, 10pm
THIS episode follows consular staff as President Trump’s controversial travel ban comes into force. The executive order halted all refugee admissions and temporarily barred people from seven Muslim-majority countries from entering the US. At this time of heightened scrutiny, staff must sort through Florida’s sun-seekers and businesspeople to spot the would-be economic migrants, terrorists, money launderers and former criminals trying to convince the person behind the window that they should be allowed in.