I use my judgment 100%. I spent a few years working in a health food store and everybody there took home the food that was "bad." The sniff and taste test seem to work fine.

I don't know, I've been hearing all this stuff about "don't trust the expiration date", so I've started to rely on smelling the food to see if it's good or not, and lo and behold... the expiration date is usually right. My milk smells sour right on the dot...

sarahisme: If you're buying the typical ultra-pasteurized stuff that most grocery stores carry, it should be good well past the expiration date (usually at least a week). Unless you're getting fresh/raw milk from your local dairy/farmers market, you might want to check the temperature settings on your fridge!

It's way off for some things. Buttermilk, for example, last a lot longer than it says.

Like my Nana always says.....it's best before, not sh*t after!

I smell the milk. When in doubt, I make my "stomach-of-steel" husband drink it. No waste, and I don't get sick! :)

And geography plays a part - NYC stuff seems to spoil faster than anywhere else in the world, and I've always wondered if that's a matter of so much food sitting on a sidewalk as it's unloaded from the truck to the store. I swear my dairy expires BEFORE the date 9 times out of 10.

I go by smell too but on testing milk or cream when I'm stuffed up with allergies or a cold, I fill a clear glass with some water (1 or 2 inches should do) and pour a little of the milk/cream in there. It's clear cut! If it bubbles up to the top and curdles it's a goner. If it swirls in with the water normally, it's fine.

I recently opened a yogurt that was over a month past it's date. It smelled fine but when I considered the potential embarrassment of explaining my choice to emergency room staff as they pumped my stomach, I decided to toss it out! :)

sarahisme: for the most part, my food does that, too.

And honestly, my digestive issues do not need to be worsened by potentially expired food.

I have to throw away a lot of milk and yogurt BEFORE its expiration date. Ewwww. Go figure.

i do check the dates on things but only to determine how fresh it is (if the milk is "expiring" in 4 days vs a week). With 2 people doing groceries sometimes you dont know how old something is! especially on things that hang around our fridge for awhile the date can be a helpful reminder when approx it was purchased. but otherwise i just use my judgement if it looks/smells bad its bad.

kren makes a good point about how the food is handled prior to purchase, it seems like my food lasts forever, but I know my usual stores dont leave food laying out they unload it right inside, probably to where it belongs. I also live just a 2 minute drive from the store. I always get refrigerated and frozen items last, they barely have time to cool before im putting them in my own fridge.

Smell test all the way. Sometimes milk spoils before the expiration date; sometimes it seems to stay good for ages.

Store-bought yogurt is a classic case. That stuff lasts forever (preservatives?). I ate a Dannon yogurt that had been in my desk drawer for six months once. It tasted normal and there were no ill effects.

Of course, you do have to be careful with some things. But typically, if it looks and smells good, food is fine.

I tend to "demote" dairy, not throw it out. I sometimes notice a very faint off note in milk well before its expiration date and well before it start to look or act spoiled. I'll use that milk in cooking that day, just not for drinking.

I notice that the grocery-store eggs get loose and unlovely well before they spoil, and well before the "best by" date, but that's a bit unfair: I'm comparing them to the gorgeous nest-fresh eggs from my sister's hens or from the farmers' market. And in 30 years of cooking (some of it at large-scale professional level, where I'd be breaking ~50 eggs in a session), I've never cracked a bad egg.

If your milk is going bad before the sell by date, your fridge probably isn't cold enough. I was having that problem for a while and it turned out our fridge was dying. Now we have a new fridge and the same milk from the same store lasts a whole lot longer.

I never keep things past their expiration date. Period. The sniffing thing makes me squirm just thinking about it.

I often eat yogurt weeks after the expiration date. They've never smelled "off" or caused me any problems.

For most foods, I'm willing to go past the expiration date if the package is unopened (even things like lunch meat). But once I've opened it, I'm much more careful and am more likely to toss.

I've eaten yogurt and eggs months after their expiration dates and never had a problem.

I always sniff, smell, and see. Companies set the dates so conservatively because they don't want lawsuits and they know a lot of people don't have commonsense about food.

We get raw milk, which has no marked expiration date. I've learned to watch it and know. Thing is, with raw milk the bacteria in it are good. Sometimes the cream I've skimmed off is thicker, which then makes it sour cream and perfectly digestible. Raw milk sours, it doesn't rot like pasteurized until much later.

Yogurt can go for a long time past if it's been properly refrigerated. The good bacteria in the yogurt fight off the bad.

I think the delivery thing makes a difference too. If something's been left out in the heat, it just doesn't stay good as long.

I meant the the cream I've skimmed off becomes thicker as it sits in the bottle I keep it in.

I always go by the theory that things will look or smell bad if they're rotten. I occasionally have to toss milk if it smells, but have never thrown out an egg, or yogurt. If cheese is really moldy I'll throw it out, but if there's just a little mold starting I'll cut it off and eat the rest of the cheese.

@Slow Lorus: That's exactly what my Dad does! Years of working in the engine rooms of large ships has killed his sense of smell but he swears by that test. He also shakes milk containers .. if they foam once shaken the protein is intact enough and it's still good. No foam, no good. That's what he claims anyway!

(Anyone else's crazy-semi-genius-engineer father do this too?)

I find that the dates are fairly accurate on milk.

I rely on my evaluation of the product. Sight and smell seem to work just fine--and result in less food waste.

I _can't_ use the smell test b/c milk always smells spoiled to me, even if it's ok (and since I live alone, it's difficult to get somebody else to test it for me). So I have to go by expiration dates. And having had food poisoning one too many times, I pretty much live by them. I wish it wasn't that way though.

I use the sniff test with food at home (with just about everything unless it's a boxed good over 6 months old) but I never buy food from the grocery store with an outdated sell-by or expiration.

Eggs ALWAYS last longer than the expiration date. I was taught to test them by filling a glass 2/3rds full with room temp water, and then putting the egg in. If it floats, it's bad. If it sinks, it's fine. I think it is because it starts to make carbon dioxide or something, and that fills the little sac inside the shell, when it goes bad, so it floats.

For milk, I am VERY cautious, as I don't really like it to begin with. Any slightly off smell, and I will not even put it on cereal.

I usually do the tea or coffee test with milk... if it's going off it tends to curdle in the hot water. I shop at Waitrose (in the UK) and they reduce everything the day before its 'sell by' date... I get milk for about .30p and it lasts ages. Sell by dates are definitely guess work.

Waste is a pretty interesting book about this subject as well... written by Tristram Stuart, I think.