I find the mustard-on-burgers thing fascinating. Outside of the US obviously ketchup is the default condiment of American food, whether on burgers or hotdogs or whatever. Mustard, if it's an option at all in the UK, is something you'd have to specifically ask for.
But it seems that (a) historically, mustard was the American condiment of choice for these foods, with ketchup a relatively latecomer, and (b) still to this day mustard much more common on burgers etc. within the US than outside the country. I see evidence of this in both burgers that you have mentioned thus far: the Damburger has mustard by default and ketchup as an extra, and the In-N-Out burger has mustard fried into the burger itself. Would be interested to hear if this is your perspective as well.
What's weird about this, to me, is that presumably ketchup was historically more alien to other countries than mustard? Mustard has been eaten for millennia, whereas ketchup in its current form is basically a nineteenth-century industrial product. It seems really odd that when American food made its way to e.g. Western Europe, such an emphasis was placed on the relatively-unfamiliar ketchup and the very-familiar mustard was dropped. Normally cross-cultural pollination of food involves changes being made to make foreign cuisines *more* familiar. But this change would seem to be the opposite. I'm sure there's some explanation, I just don't know what it is.
Do you have any sense of this as someone with experience of living (and, presumably, eating burgers and hot dogs etc.) both in and outside the US? For what it's worth, I would never have had mustard on my burgers until basically this year, but now I do it all the time.
Thanks for the thought-provoking (!) comment! ChatGPT gives the timeline as follows (apologies for my laziness):
"The use of ketchup on burgers became popular in the United States around the mid-20th century, although pinpointing an exact date is challenging. Initially, mustard was the more common condiment for hamburgers, partly due to its association with hot dogs, which were popularized earlier.
Here’s a brief timeline of the transition:
Early 1900s: Hamburgers started becoming popular in the U.S., especially with the rise of fast food establishments like White Castle, founded in 1921. During this period, mustard was often the condiment of choice, along with onions and pickles.
1930s-1940s: The popularity of ketchup began to rise, partly due to the influence of the Heinz company, which had made ketchup a household staple by standardizing its recipe and ensuring wide distribution.
1940s-1950s: Post-World War II America saw a boom in the fast food industry with the expansion of chains like McDonald's, founded in 1940. McDonald's originally served their burgers with mustard, ketchup, onions, and pickles.
1950s-1960s: As fast food chains proliferated and ketchup became more widely available, its popularity as a burger condiment grew. By this time, ketchup was becoming a common addition to burgers, sometimes replacing mustard entirely or being used alongside it.
1970s-1980s: Ketchup solidified its place as a primary burger condiment, often accompanied by mustard but sometimes as the sole condiment.
The shift towards ketchup can be attributed to several factors, including its sweet and tangy flavor, which complements the savory taste of burgers, and its widespread availability and marketing by major food companies like Heinz. Today, ketchup is a ubiquitous burger condiment, though mustard remains a popular choice as well."
My guess is that hot dogs and hamburgers were popularised in places like Britain after the transition to ketchup had taken place. So, other than in places where Bratwurst etc with mustard (or ketchup!) was a common street food, there was no precedent for converting the condiment of choice 'back' to mustard.
Also, while tomato ketchup is an early 19th-century invention, ketchup is much older, having evolved from Asian fermented fish sauces (soy sauce is still 'kecap' in Indonesian). In early modern England, mushroom ketchup was the most common version. Modern ketchup is very much not funky and fermented, like those sauces were. Its likely that its sweetness is just much more palate-pleasing to many modern palates than mustard. And mustard on burgers, while relatively common in the US compared to elsewhere, is definitely seen as the 'old-fashioned'/'traditional' option.
Wouldn't have had you pinned as a ChatGPT searcher! Not to say anything bad, just surprising how it's proliferated.
I have actually seen that (excellent) video on ketchup, which is part of why I said "ketchup in its current form": it's historically fascinating that ketchup evolved from the same place as Indonesian sweet soy sauce (and indeed I've cooked with kecap before, stir-frying tempeh). But equally, if you went back to what is now Indonesia two centuries ago with a bottle of Heinz, none of them would recognise it. Whereas I could take the hot mustard in my fridge back to Roman Britain and it would be basically familiar.
That's the particular variable I was playing on: familiarity. But I think you must be right, that in the case of ketchup the "very sweet, little sour, little savoury" taste combination is palate-pleasing enough to have outweighed its unfamiliarity to British palates. Normally you have to learn to love a new food; but ketchup takes no learning.
I find the mustard-on-burgers thing fascinating. Outside of the US obviously ketchup is the default condiment of American food, whether on burgers or hotdogs or whatever. Mustard, if it's an option at all in the UK, is something you'd have to specifically ask for.
But it seems that (a) historically, mustard was the American condiment of choice for these foods, with ketchup a relatively latecomer, and (b) still to this day mustard much more common on burgers etc. within the US than outside the country. I see evidence of this in both burgers that you have mentioned thus far: the Damburger has mustard by default and ketchup as an extra, and the In-N-Out burger has mustard fried into the burger itself. Would be interested to hear if this is your perspective as well.
What's weird about this, to me, is that presumably ketchup was historically more alien to other countries than mustard? Mustard has been eaten for millennia, whereas ketchup in its current form is basically a nineteenth-century industrial product. It seems really odd that when American food made its way to e.g. Western Europe, such an emphasis was placed on the relatively-unfamiliar ketchup and the very-familiar mustard was dropped. Normally cross-cultural pollination of food involves changes being made to make foreign cuisines *more* familiar. But this change would seem to be the opposite. I'm sure there's some explanation, I just don't know what it is.
Do you have any sense of this as someone with experience of living (and, presumably, eating burgers and hot dogs etc.) both in and outside the US? For what it's worth, I would never have had mustard on my burgers until basically this year, but now I do it all the time.
Thanks for the thought-provoking (!) comment! ChatGPT gives the timeline as follows (apologies for my laziness):
"The use of ketchup on burgers became popular in the United States around the mid-20th century, although pinpointing an exact date is challenging. Initially, mustard was the more common condiment for hamburgers, partly due to its association with hot dogs, which were popularized earlier.
Here’s a brief timeline of the transition:
Early 1900s: Hamburgers started becoming popular in the U.S., especially with the rise of fast food establishments like White Castle, founded in 1921. During this period, mustard was often the condiment of choice, along with onions and pickles.
1930s-1940s: The popularity of ketchup began to rise, partly due to the influence of the Heinz company, which had made ketchup a household staple by standardizing its recipe and ensuring wide distribution.
1940s-1950s: Post-World War II America saw a boom in the fast food industry with the expansion of chains like McDonald's, founded in 1940. McDonald's originally served their burgers with mustard, ketchup, onions, and pickles.
1950s-1960s: As fast food chains proliferated and ketchup became more widely available, its popularity as a burger condiment grew. By this time, ketchup was becoming a common addition to burgers, sometimes replacing mustard entirely or being used alongside it.
1970s-1980s: Ketchup solidified its place as a primary burger condiment, often accompanied by mustard but sometimes as the sole condiment.
The shift towards ketchup can be attributed to several factors, including its sweet and tangy flavor, which complements the savory taste of burgers, and its widespread availability and marketing by major food companies like Heinz. Today, ketchup is a ubiquitous burger condiment, though mustard remains a popular choice as well."
My guess is that hot dogs and hamburgers were popularised in places like Britain after the transition to ketchup had taken place. So, other than in places where Bratwurst etc with mustard (or ketchup!) was a common street food, there was no precedent for converting the condiment of choice 'back' to mustard.
Also, while tomato ketchup is an early 19th-century invention, ketchup is much older, having evolved from Asian fermented fish sauces (soy sauce is still 'kecap' in Indonesian). In early modern England, mushroom ketchup was the most common version. Modern ketchup is very much not funky and fermented, like those sauces were. Its likely that its sweetness is just much more palate-pleasing to many modern palates than mustard. And mustard on burgers, while relatively common in the US compared to elsewhere, is definitely seen as the 'old-fashioned'/'traditional' option.
P.S. History of ketchup from one of my favourite YouTubers: https://www.youtube.com/watch?v=iWlqxGQXZx8
Wouldn't have had you pinned as a ChatGPT searcher! Not to say anything bad, just surprising how it's proliferated.
I have actually seen that (excellent) video on ketchup, which is part of why I said "ketchup in its current form": it's historically fascinating that ketchup evolved from the same place as Indonesian sweet soy sauce (and indeed I've cooked with kecap before, stir-frying tempeh). But equally, if you went back to what is now Indonesia two centuries ago with a bottle of Heinz, none of them would recognise it. Whereas I could take the hot mustard in my fridge back to Roman Britain and it would be basically familiar.
That's the particular variable I was playing on: familiarity. But I think you must be right, that in the case of ketchup the "very sweet, little sour, little savoury" taste combination is palate-pleasing enough to have outweighed its unfamiliarity to British palates. Normally you have to learn to love a new food; but ketchup takes no learning.