If the packet is unopened and kept out of sunlight, it will last almost indefinitely. (At least 4 years, most likely more.) If the packet is opened but with an airtight seal (e.g in a tupperware box), it should last for at least a year. If the packet is opened and not resealed thoroughly, it will last a couple of weeks.

Once the dried milk has been rehydrated into milk, it will last approximately 3 days refrigerated.

Yes, it has milk products in it.

a pantry or someplace that is dry with low humidity

yes add a couple of ring dings and it is perfert to eat

I'd imagine that if the casserole contained dairy or dairy products such as milk, cream, or cheese, then it may have a hard time staying fresh without refrigeration. The lactic acid bacteria added to milk after pasteurization ferment lactose at room temperature, causing a sour taste and residual curdling. Refrigeration is never a bad idea if you're in doubt!

Salt has been used as a food preservative for thousands of years, so it will keep indefinitely unless it is contaminated with foreign substances or gets wet and/or hardens. Kept clean and dry it will keep indefinitely. You can keep salt dry from humidity by putting a few grains of uncooked rice in salt shaker with it.

Doritos have a "Guaranteed fresh by" rather than an expiration date. On the bags I have, it is an open code on the front of the bag listing the month and day, such as "JAN 3". There is no year since the recommended shelf life is only about 2 months from the production date.

It depends on how it was stored. In the freezer a couple more months. In a hot room, throw it out.

Actually, flour definitely expires and turns. Storage can affect it, but even in a dry, low-humidity, dark cabinet, it will eventually go bad. I wouldn't keep it more than a few months after the expiration date. I baked cookies with expired flour 8 months past the date, and they tasted bad.

This goes for pancake mix as well.

There are plenty of crazy stories out there about chemicals added to freeze dried coffee. There is no reason for anything to be added to coffee when it is freeze dried; the entire point of freeze drying is that it preserves the product naturally. The process is: they make some coffee; they freeze it; they dry it.

In short, whatever chemicals are in freeze dried coffee are only those - and exactly the same as those - found in "fresh" coffee.

It all depends whether it is a sell by date, use by date, or a best before date. If it is a sell by, then that would be an earlier date than an 'eat by' date so it would probably be OK. If it is a best before, then it probably won't taste as good but will still be safe; if it is after a use by date then it may not be safe so you shouldn't eat it.

Because bulgur is precooked, it has a very long - almost indefinite - shelf life.

Yes all mash poataoes go bad. i would keep it in the freeze make sure all the air is out

The espresso coffee bean is from roasted from the arabicaspecies that contains 60% fat soluble lipids responsible for the essential coffee aromatic oil. The aroma of the espresso bean on shelf preservation undergoes a slow chemical change like all coffees. Oxidation occurs and the bean/grounds will stale.

2 weeks

In an airtight container in a cool place, away from light.

If it is freshly made and that is part of the recipe's flavor profile, then it would be OK. If this has been sitting around for a while and it is an unexpected flavor, then I would not recommend eating it. When in doubt, throw it out.

Yes, if they are not protected from moisture, heat and light.

If properly stored, they could last for years. In a waterproof container, they can keep up to 2 years. If stored hermetically sealed and in the absence of oxygen, they can last even longer. See Related Links.

The expiration date on chocolate isn't due to food safety. It is a shelf stable product. The concern would be with flavor. Chocolate can become stale or rancid. Tasting it would be up to you.

Yes. It will be fine for about 5 years or so after the given expiration date. The given expiration date on the package is just concerning the actual color quality, not any health concerns. So your good to use it.

how old is bread Good Bread is not older than a day or two

If properly packaged, almost as long as you need. My grandmother is a testament to that. Although, I would say after 9 months or so freezer burn will begin to happen either way.

Depends on location. Different locations, different regulations apply.

Once opened, mayonnaise should be refrigerated. The same is true for homemade mayo.