Today, millions of people will assemble their favorite filling between two slices of bread in honor of National Sandwich Day.
There are certainly few snacks that capture the world’s heart like the sandwich, which is said to have been invented in 1762 by John Montagu, the 4th Earl of Sandwich.
It is known that he was playing cards and did not want to leave the gaming table to eat, so he asked for a portion of beef, placed between two slices of bread, which he could eat with his hands.
More than 250 years later, fierce debate still rages about the best fillings, the art of building it and even how to eat it.
To settle the debate once and for all, food scientists have revealed the formula for the perfect sandwich.
According to the academics, the perfect sandwich has a symmetrical arrangement, with the wetter elements placed in the center.
These wetter elements are usually the salad ingredients that provide an essential crunch – so tomato, lettuce, or perhaps some pickle or pickled onion.
‘Wet fillings, such as tomato slices, should be sandwiched in the middle and insulated to prevent the bread from becoming soggy,’ says Charles Spence, professor of experimental psychology at the University of Oxford.
According to scientists, the perfect sandwich has a symmetrical arrangement of the filling and a sturdy sandwich filling with butter at room temperature in between.
During construction, instead of building your sandwich from the bottom up, place both pieces of bread side by side and add each filling sequentially.
“The trick is to place both pieces of bread side by side, then spread them out, place primary fillers on each slice and finally add the salad in the middle and place them together,” says Alan Mackie, professor of nutrition and nutrition at New York University. Leeds.
When choosing your bread, you should choose one that will not easily become squashed or soggy, such as sourdough, whole wheat or brown.
Professor Spence says: ‘The fundamental purpose of the Earl of Sandwich’s invention is to keep hands clean, potentially excluding greasy breads such as focaccia.’
The two slices should not be so thin that they fall apart, but neither should they be so thick that they are too difficult to eat – about 2 cm is sufficient.
Then some kind of essential element of the fat emulsion must be spread to the edges of the bread.
This not only adds an unctuous fatty flavor, but also creates a seal that repels moisture – another trick to keep the bread from becoming soggy.
Professor Spence says butter is preferable to margarine, an ultra-processed food, while another alternative, mayonnaise, is ‘simply disgusting’.
You should choose a sturdy loaf that will not easily become squashed or soggy. While the choice of fillings is personal, scientists find it important to consider exactly how they are arranged
The butter should be at room temperature (20°C) so that it is soft enough to spread, otherwise it may tear holes in your bread.
The meat and cheese you choose, which also contain a lot of fat, further prevent unwanted moisture from getting anywhere in the bread.
Professor Mackie thinks it’s worth folding your meat if possible, rather than laying it flat, which creates a bigger barrier.
But an extra precaution to ‘prevent sagging’ is to make sure you pat your lettuce, pickle or onion dry with a kitchen towel or use a salad spinner.
Meanwhile, tomato is a risky addition because it contains so much water, which can also dilute the overall flavor of the sandwich – so you may want to reheat it in an oven or a food dehydrator.
If this sounds like too much hassle, Professor Spence emphasizes that the salad is an essential element in delivering the ‘sonic crunch’ when bitten into, with more sound associated with greater satisfaction.
“Since we all like crispy, crunchy and crunchy foods, make sure some fillings are appealing to the ear and help signal freshness,” he said.
“That’s where pickles come in, or a slice of fresh onion, although others cheat and throw in some chips right before they eat it.”
Few snacks capture the nation’s heart like the sandwich, which is said to have been invented in 1762 by John Montagu, the 4th Earl of Sandwich.
By including the widest possible range of colors in a burger, ‘what we eat can look more attractive’, from the green of the lettuce to the red of the tomato.
‘The more vibrant the colours, the better,’ Professor Spence told MailOnline.
“Imagine how boring a tuna mayo filling looks in a white sliced bun.”
Eaters should also make sure that their filling always visibly protrudes from the sandwich so that it is more noticeable.
Finally, Professor Spence, who has written extensively about how people perceive food, warns that “adding more layers is not always better.”
‘Never forget the narrow opening into which the sandwich should enter the mouth,’ he told MailOnline.
‘Make sure it all hangs together so that the filling doesn’t fall out of your sandwich from plate to mouth.’