…that is the question.
Does it really need to be put in the fridge?
I worked in a restaurant for over 5 years and we never refrigerated ours. Come to think of it, my bottle doesn’t say anything about refrigeration.
When my room mate saw said bottle, she yelled at me for not refrigerating it.
So who’s right? Me for keeping my bottle out of the fridge or my roomie for keeping her bottle in the fridge?
When I worked at restaurants they never refrigerated them either.
But, probably you and I keep ours longer than the restaurant does (theirs gets used up faster). So to be on the safe side, I put mine in the fridge.
Definitely in the fridge. Ketchup (or any one of the alternate spellings) will go rancid. Probably, in the restaurant biz, it gets used so quickly there’s no danger in this. Also, restaurants are much more temp-controlled than my house, which gets damned hot in the summer!
Strangely, the opened bottle stays in the cupboard, we also have a ‘squeeze container’ which gets refilled from the bottle in cupboard, but the squeeze bottle stays in the fridge.
So, we swing a little both ways.
On occassion we have had a little mould around the top of the bottle in the cupboard, so it will spoil, but I’m sot sure how long it takes.
Oh, and then we throw that bottle out.
We keep our’s next to the sofa. We go through about a half litre per month, and no known cases of food poisoning yet!
I’ve noticed that the flavour goes off after a while if I don’t refrigerate it. It takes me forever to use up a bottle of ketchup, though.
Every restaurant I’ve ever worked in refrigerates the ketchup at night.
Of course, this is after it’s been sitting on the tables for up to eighteen hours at a time, and several people have handled it, and the servers have “married” half bottles (some of which may be older than others) and the insides of the bottle necks have been wiped with a damp cloth to look fresh and new. (Incidentally, condiment marriage is a practice that is frowned up on by health departments everywhere.)
Ours gets tossed in the fridge. I’d never considered just leaving it out.
We put ours in the fridge. Warm ketchup is just too strong-tasting for my taste.
Since they came out with the spastick squeeze bottle to the fridge they go. In fact, never had one go green. Till I saw one in the grocery store. I thought “what> green tomatos”!?!
Warm ketchup? YUCK!
I keep it in the fridge, so when I combine it with hot-from-the-oven tater tots, the temperatures seem to even out and I don’t burn my mouth as much. Then again, I’m from Indiana. 
Upon further investigation, my squeeze bottle of Del Monte Ketchup instructs to “refrigerate after opening.” So I’m simply following directions… 
And, LifeOnWry, you have just ruined restaurant ketchup for me. I am completely grossed out and horrified. The insides of the bottle necks? eeeewwww
Good question. I refrigerate. I tend to think it’s liable to stay “fresher” if it’s in the fridge although cupboard kept ketchup doesn’t really bother me. I’ve seen it done both ways.
I’ve had ketchup go bad (it actually fermented I think) in the bottle unrefrigerated (this was before we had children and a small bottle would last six months), so I always keep it in the fridge now, but it’s probably more a peace-of-mind thing than any real benefit - refrigeration only slows down the process (you can even prove bread dough in the fridge, it just takes a couple of days).
I refrigerate after opening - I like it cold.
When in doubt, refrigerate…
ok, seriously, I refrigerate. We don’t eat it fast enough for it to not spoil if I didn’t.
Growing up on the east coast, we always put the butter in the fridge and the ketchup in the cabinet. Went I went out west to college (Utah, to be exact) I met lots of people who did the exact opposite (they claimed that butter didn’t need to be refridgerated and leaving it out kept it soft, yet insisted that ketchup HAD to be refridgerated or it would go bad).
East is east, and west is west, and never Mark Twain shall meet…
Barry
It says “refrigerate after opening” on the bottle and that’s what I do. Come to think of it, I even refrigerate before opening. The Heinz consumer FAQ have the following to say about ketchup refrigeration:
Because it is a very acidic product, ketchup does not spoil easily. Once opened, in order to maintain the product’s quality more effectively, we do suggest that ketchup (and any other processed food) be refrigerated after opening because refrigeration retards spoilage.
I keep a bottle of ketchup in my desk at the office for when I work late or work on weekends. And also, believe it or not, a squeeze bottle of mayo. I have done this for over 4 years and nothing has spoiled so far.
Ketchup does not have to be refrigerated.
We refrigerate. Cold ketchup, hot curly fries! YUM!
I do have a bizarre soy sauce situation, though. I keep the huge bottle in the pantry, and the small bottle stays in the fridge.
Mayo on your desk, Khadaji? Weird 
My husband and I had to argue about the peanut butter. He won. It’s in the pantry.