lostzombies.com said:
sniff test, you can tell with the vast majority of food/drink if they are off by sniffing it
This is a bit of a misnomer, as some highly acidic foods like marinara sauce can smell almost the same after 4 weeks as they can after 4 days, but be crawling with gut-displeasing microbes. Would you eat month-old leftover spaghetti sauce?
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Because I'm bored, I'll share this stuff and pretend I'm being helpful.
Canned vegetables, or so I hear, are good for a very long time, as long as the can isn't bulging or dented. A lot of people confuse "Best taste by" with "Do not eat after." They're still perfectly edible, for several years past the date.
Eggs have a very long shelf life. Eggs can be good for a few weeks past the sell-by, which are generally a couple weeks to begin with.
Even Low-Temp Pasteurized-Process milk that has a slightly tart smell is still technically good, if it's only slightly soured. It's pretty much just buttermilk, and is great for cooking. And probably won't cause discomfort to drink, even if it is slightly unsavory. If it's starting to form larger chunks and smells VERY tart, it's pretty much unpalatable and inedible.
Some people cut the mold off of cheeses and breads and eat the unfruited part. This is not smart. All you see on the surface is the fruiting body of the mold. By the time it is fruiting, pretty much the entire food is infiltrated by almost invisible strands mycelium, which is largely invisible, but still definitely fungal. Some of these can be unpleasant to eat.
...that's all I got on the subject.