So THAT's Why Supermarket Sandwiches Have So Much Mayo

I had no idea.
Andia Andia/Universal Images Group via

We’ve written before at HuffPost UK about how Hobnobs got their name, as well as how Yorkies’ clever design actually only uses a gram more of chocolate than Dairy Milk.

But what about another food manufacturing marvel ― the supermarket sandwich? I love a meal deal, but hate mayo ― how come every offering seems to be brimming with it?

Thankfully, the Channel 4 documentary Food Unwrapped: Lunchbox has all the answers.

Speaking to Dan Silverston of the Soho Sandwich Company, which makes over eight million sandwiches a year (woah), they asked, “why so [supermarket] sandwiches have so much mayonnaise in them?”

What’s the answer?

Silverston ― who says his company gets through about two tonnes of mayo a week ― says that part of the reason is because it’s more spreadable than butter.

It’s also “great at providing that barrier” between bread and filling, Silverstone adds.

“There’s nothing worse than a soggy sandwich.. ’cause of the oil content in mayonnaise, [it] stops tomatoes leaching into the bread,” he explained.

The final reason why they use mayonnaise is that it’s a seriously effective flavour carrier. Silverston showed the Channel 4 presenter a litany of flavoured mayos, including gravy and chipotle-infused options.

When asked why he didn’t simply season the sandwiches with those flavours, Silverstone explained that because of mayo’s aforementioned spreadability, it gets the taste “corner to corner” in the sandwich.

“You’re getting a consistent result every time,” he shared. Instead of dry powders or hard-to-spread liquids which might disproportionately clump in some areas of sandwiches, infusing them into a mayo means every bite has the same taste.

What if I hate mayo?

I’m with you. And Channel 4 found that at the time of airing their documentary, “39 out of 46 [sandwiches] in Tesco” have mayo in them; as, they say, do “29 out of 36″ in Sainsbury’s.

Perhaps ingredients like pesto, whose fat content might also help to combat that annoying sogginess, could work as an alternative for us mayonnaise maligners; hummus may do the job, too. Both are also easy to spread.

But when it comes to the bulk of supermarket sandos, I regret to tell you this ― it doesn’t seem like mayonnaise is going anywhere in a hurry.