"I always leave the squirrel monkeys until last," explains exasperated Senior Keeper Hannah Duprey, as she meticulously prepares a breakfast.
Recipes are chalked up on the wall. For these monkeys, aubergine (100g), courgette (100g) and potato (200g) must be chopped and lightly steamed. Half a kilo of broad beans and sweetcorn, still frozen, are served in a separate tub. Snacks include pecan nuts, wax worms and soft fruit.
As you might imagine, feeding the animals at London Zoo is a fiendishly complex logistical operation. Each creature has their own nutritional needs, quirks and foibles.
Menus are changed regularly - to maintain their interest - and the fruit and veg must be seasonal and represent good value.
On the day of my visit, some animals dine on fresh asparagus and radicchio. And there are, of course, zero days off for the staff: the inhabitants of London Zoo are ravenously hungry 365 days of the year.
Catering supply company Covent Garden Supply won the tender to supply both London Zoo and Whipsnade Zoo. "Serving the animal kingdom is a challenge but one that we relish," says account manager Nicolette Davidson. "They are a unique customer."
The company delivers pallets of fruit and veg several times a week, each carefully pre-packed for distribution to the various animal sections.
"Covent Garden Supply do a lot of work with our nutritionist to suggest alternative foods that are in season and offer the same nutritional value," explains the zoo’s Procurement Manager Gwynne Morgan.
In recent years, the team at the zoo has worked hard to reduce the amount of fruit in the animals’ diets. "The primates are like children - they go for their favourites foods first," says Duprey.
"The fruit we have over here is cultivated for human taste – very sugary and very watery, which is not what they would get in the wild." Duprey explains how wild fruit is often more fibrous and sour, eaten at different stages in its development.
She adds: "So the fact that we give them carrot, sweet potato and corn on the cob – there’s lots of nice sweetness in there but it’s not the fruit sweetness. And actually the root vegetables and all the leafy greens are much better for them nutritionally."
Animals on her section (Mammals South) include western lowland gorillas, bearded pigs, monkeys, kangaroos, tapirs and emus. Their menus included asparagus, radicchio, chicory, kohl rabi, curly kale, Savoy cabbage, Chinese cabbage, carrots, broccoli, lettuce and sweet potato.
Meals are not just a single serving. "We don’t just present them with a tray of food," states Duprey. The zoo also provides "scatter feed" such as popcorn, which are snacks that the animals have to forage and find.
Inventive additions include lollies made with Twinings fruit tea and seeds. For the pigs, the keepers bury soaked fruit berry tea bags to snuffle and forage.
Sustainability is a feature of this work. American Signal Crayfish, an invasive species caught from the capital’s waterways, are fed to animals such as the otters.
"Browse" is another element: leafy material grown and harvested by the zoo’s horticultural team from the zoo grounds. "For a lot the animals that would be much closer to their natural food sources," says Duprey.
This glimpse behind the scenes of London Zoo was a real eye-opener. Keeping the animals happy and healthy is gigantic team effort and the market plays a vital role.
ZSL London Zoo
0344 225 1826
Covent Garden Supply
C6 - 11 Fruit and Vegetable Market
New Covent Garden Market
020 7720 8888