There seems to always be a contentious debate between the pantry crowd and the fridge crowd. The pantry crowd insists with almost religious zeal that you can store pretty much everything in the pantry. Why did they even invent refrigerators for, anyway? Heck, even your eggs can be left out at room temperature, according to the pantry police. Then there are the folks who throw everything in the fridge, including onions, old gym socks, and half-eaten tuna sandwiches. So, of course, there are passionate debates taking place right now about whether you should store America’s favorite condiments, ketchup and mustard, in the refrigerator. I’m going to settle this debate. After all, if you can’t trust Culinary Lore, who can you trust?
Does Ketchup and Mustard Need to be Refrigerated?
So, my ketchup bottle, Heinz, of course, says ‘for best results, refrigerate after opening.’ And my mustard bottle, French’s, tells me ‘for best flavor, refrigerate after opening.’ You’ll find similar statements on most of the other brands. The manufacturers are not saying that you MUST refrigerate the products, but that you probably should if you want them to taste the way you expect. Maybe you don’t trust Culinary Lore, but shouldn’t you trust the manufacturers?
Both ketchup and yellow mustard are highly shelf-stable. They can both be left at room temperature (with the container closed) for long periods of time, safely. They both contain vinegar, an acid, and this acidic environment will retard bacterial growth. The tomatoes in ketchup are also acidic in their own right. As well, ketchup is highly sweetened, and this high sugar environment also retards bacterial growth. Mustard seeds themselves exhibit antimicrobial effects and the powdered mustard used in the prepared mustard will retard bacterial growth. All in all, both condiments are unfriendly to the well-being of a microbe.
But let’s remember that almost everything, especially things that are wet, goes bad. When you store your ketchup and mustard at room temperature, as in the pantry, it is quicker to undergo changes due to oxidation, which will break down the product and cause color and flavor deterioration. This is why manufacturers want you to refrigerate them, so that you get the best experience possible.
In general, an unopened bottle of ketchup will last about a year in the pantry. After opening, if left at room temperature, it will start changing for the worse within a couple of weeks and after a month or two at most, it may not make you sick but will taste strange. On the other hand, ketchup will last about six months after opening in the fridge.
According to most sources, mustard doesn’t fare as well in the pantry, only holding up for one or two months, while it is still good for up to one year, after opening, in the refrigerator.
You are Not a Restaurant
A favorite argument of the pantry-worshippers (stop with your dirty mind) is that restaurants don’t store their ketchup in the fridge. Well, some restaurants do refrigerate their ketchup at the end of the day. And even if they do not refrigerate the bottles of ketchup on the table, they may keep the bulk bottles they use to pour from in the fridge.
But, also, restaurants go through those small bottles of ketchup much more quickly than we do at home, so they know that the quality will be maintained for the short time the bottle is used.
One drawback is when restaurants continually refill half-empty bottles so that some of the ketchup is never used and sits at room temperature for extended periods. All bets are off.
You do not have to store ketchup or mustard in the refrigerator and if you really like them to be warm, go ahead and keep them in the pantry. I’d recommend for best results, though, that you buy smaller containers that you can go through quickly. For the best overall results, however, just like the makers say, refrigerate after opening.