What's the greatest extent (as in the most amount of time) to which you've eaten something past its expiration date with the food still being enjoyable?

Vinegar based hot sauces are basically immortal; I've had Tabasco that was like 10 years old before

Isn't it ten years old by default?
- I have no idea if it's an aged sauce. Regardless, I meant it was opened many many years prior
Does it lose any of its hotness?
- It separated out to half clear vinegar and half... Red
  
  You had to shake it back together but if anything it was even hotter than usual. It was wild
- I think heat typically intensifies over time: anecdotally, leftover hot food is always hotter a couple of days after it was freshly made

I have some spices that are probably pushing 15 years that are just fine.

In Europe we use expiration and best before dates.

With exp. dates, don't push it: they mean after that date, the food could spoil and there's biological risk on eating it. One day? Ok. 3 days... only if you have to and after looking closely for signs of spoiling. Cook it thoroughly.

With BBF dates, there is no risk unless evident contamination, meaning that after that date, the food will be edible but might have a different taste. Obviously, look for mold if the product was open, bwt it's generally safe to eat even after years. Except fresh uncooked food, almost everything else falls in this category here.

Edit: typo

Very good explanation! The wording varies, in Czech and German it's like "consume by" and "can be stored at minimum until".

A store in my country once had an apology sign on display saying something along the lines of:

Some products in [this section] on sale [this year] were labeled with a "Sell By" date. According to [this EU directive], such a date is identical to the "Best Before" date. This has been fixed and we apologize for any confusion."

I have no idea how the "mistake" happened (normally, no food items share packaging between Europe and other continents) but I'm glad they got it sorted. The "Sell By" bullshit causes industrial-scale food waste by US supermarkets. Here, items about to pass BB are marked down by about 30% instead, and mom-and-pop stores usually have a discount shelf dedicated to past-BB items at 50% or higher discounts.
Do things that have a BBF date expire if you wait years?
- As they said, generally no, they may just not taste as good.
  
  For example - a pot of chilli powder probably will be fine after 5 years unopened in a cupboard, but probably won't be as spicy as it used to be.
- If well stored and with undamaged packaging, it can go for years without trouble. With bff products i generally go to groceries stores and look for a section dedicated to these products. They sell them cheaper and are completely safe. Good way to save money and fight food waste.

i ate a pound of pistachios that were 30 years old, and couldnt stop eating them, so delicious.

That's older than I am. That's nuts.
- I see what you did there 😉
Unless stored in some unusual way, the nut oils would almost certainly have been rancid. Not very healthy for you, but wouldn't give you food poisoning. Salt can hide the taste of rancid oils.
- yea i believe you. these were in a jar without a lid and were dusty. Gen-X kids are hardcore, especially when hungry and broke.

Actual food? Probably yogurt at like one or two months. It had been sealed up until then.

I've had table syrup that was at least 4 years past the expiration (it actually still had the aunt Jemima on the bottle is how old it was).

A few days ago I finished some baking powder and my partner brought a big bottle home and I was like "oh it's okay that stuff doesn't expire!" Then I looked at the previous container I had and found out it had, in fact, expired in 2017. Don't think it affected my baking though.

I mostly just eat stuff without looking at the dates unless it smells bad or is moldy.

Syrup I always thought was like honey. It comes from tree sap and that can even be fermented.

Aunt Jemima be like "I'm still here, critics!"

There's some mayonnaise in the fridge a couple years old I'll use on sandwiches. After family holiday get togethers there's always leftover ham or turkey, that's about the only time I'll use mayonnaise. Every year I'll pull it out, look at the expiration date and make a choice. Go get a new jar that will only get a third used or live life on the edge and slather on the old stuff. I call it refrigerator roulette

Some brands of mayo actually say on the jar that you don't need to refrigerate them. In the fridge, I'd probably keep that 2 or 3 times longer then the jar claims it should last.
That moment when mayonnaise is an instrument.

This depends on the type of food.

Fresh meat? Don’t push it.

Tofu? What, is the bean curd going to curdle?

Tofu will go bad, it will turn sour and slimy. Or at least the soft tofu will. Pretty sure all tofu will be eventually.

I think a lot of people are confusing the “best by” or “sell by” etc. dates on foods (in the USA anyway) with an “expiration” date. The only foods in the US that actually have expiration dates are infant formula. NO foods expire exactly on some arbitrary date stamped on the packaging. The dates are listed to give consumers an idea of when they should think about consuming the product, many with a large amount of useable time after the date printed.
Don’t believe me? Here is the USDA’s FSIS explanation of their own regulations.

So you're saying meat doesn't have an expiration date?

In 2011 I was in an unfamiliar kitchen and had some porridge in the morning. I put some ground cinnamon on it that was in the cupboard and noticed that it was particularly good cinnamon, much more flavoursome than I was used to. I looked at the bottle again and it was the same brand I always use myself at home so I didn't see why it should be so much better but I noticed that the although pretty similar the labelling seemed subtly different than I was used to. I looked at the expiry, it expired in 1986 and the label was different because they'd updated the design since. I don't know why the 25 hear old cinnamon seemed to taste so extra good, I would have thought that if it wasn't somehow rotten and sloiled it'd at least have lost basically all its potency but somehow it was super nice. I even had extra after this discovery.

Was it a certain brand? If nothing bad happened due to eating cinnamon older than I am, that's amazing.

Maybe I should do this for my 25th birthday next month, celebrate with 25-year-old cinnamon that may have been born when I was.
- Yeh it was Masterfoods ground cinnamon if I recall. It really defies intuition because things like nice aromatic spices should get progressively weaker flavoured over time. I feel compelled to say this may have been a freak occurrence and it's probably unwise to seek out 25 year old spice.

I've eaten pasta from a sealed, unopened bag that was 4 years past the date. The only difference I noticed was a few pieces breaking apart after cooking and it maybe cooked a tad faster.

Imagine a bag of minute pasta saying "warning, after expiration, pasta may cook in 59 seconds".
- I've had the opposite experience. The older the pasta, the longer it takes to cook. If it cooks faster, that suggests to me that it has absorbed water during storage, which allows harmful bacteria to grow and the pasta might actually be expired.
- "Reduce cooking time by 2 seconds for each month past expiration."

I understand in some cases it may be wasteful, but I'm super strict about expiration dates. Food poisoning is truly awful, and I don't fuck around. All that barfing, shidding, and farding.

It is wasteful, the expiration date is very conservative. You can push it 20% or more for sealed, correctly stored items. Just check for signs of rot or mold. Food waste is a serious problem in first and second world countries.
- No thanks.
- Which is cheaper — composting food after its expiration date, or the copay at the doctors office when you get food poisoning?
If it's meat, I typically follow that advice, though they make the expiration dates otherwise super difficult to find (if at all) and I usually find out in hindsight, and so over time, I have become used to just not thinking of the expiration dates unless an actual issue. I was with some friends the other day and they were amazed I was eating a nutrient bar that was almost a year past the date (still waiting for the side effects, which in a way surprises me as that would be my answer). Usually for them, once the expiration date comes, they just throw a thing outside for the animals (which I do very infrequently; typically I employ foods I don't trust as art materials as I discovered it helps that hobby).

I just used up a bag of dried dates that were a couple years past the date on the bag. They weren't noticeably different from when new. (They went into something baked so also seemed less of a big deal.)

been drinking liquor, that "expired" in 1937

I found oatmeal from 2001 in the pantry a few months ago and it was still good so I ate it.

The 1kg Vegemite jar that was hand down to my by my father, and I hope to someday pass it down to my children when they are worthy

Pasta, 12 years. Yoghurt, 1 month.

I'm impressed in a way that anything could be good up to twelve years past the expiration date.
- Dry and sealed, it can last decades. Honey can last centuries but will usually expire after 1 year for legal reasons.

I'm thinking about this and not sure but have made fruit syrups for cocktails, recipes said they last a week in the fridge, but still tasted great after a year. I always just use those until they are gone, but all I had were lost in the hurricane as we had no refrigeration for a week.

Buttermilk always seems to have like a one week expiration, but always seems to be fine up to maybe 2 months surprisingly

Assuming it's cultured buttermilk, you can keep it going by adding milk when it's almost gone, then leaving it on the counter overnight. It's like yogurt but more robust, less fussy.

Rice, 10 years. Beef, hmmmmmmm 2 months? Mushrooms at least a year. Got to let them be fun guys.

The kind of mushrooms from the grocery store or the kind of mushrooms likely secretly sold under the grocery store?

About 15 years. I can't remember exactly... something from the "small things corner" of our fridge :)

I haven't even had a fridge last that long.
- Oh. You poor slave to consumption.

Permanently Deleted

I rarely press my luck either, though mostly because the fact I know how to use what I buy and buy what I use makes it so I'm not used to finding something that's past an expiration date. It used to be (and this is still slightly the case) I had to be "urged" to be afraid of it by people who were amazed I'd happily take anything regardless of a date.

Maybe a day by accident at most.