16 Burning Questions You've Always Wondered About Common Ingredients

Are heavy cream and whipping cream the same thing? Not exactly. All cream contains at least 18 percent milk fat, and "whipping cream" is made up of 30 percent. Cartons labeled "heavy cream" or "heavy whipping cream" must contain 36 percent or more. Any of those will work in a recipe that requires cream, but regular half-and-half won't (it contains less milk fat).

Refrigerating butter is a bit of a debate, but here's the best practice. Unsalted butter is best left in the fridge at all times, but salted butter is less prone to bacterial growth because of its sodium content, so it can be kept out of the fridge (in a butter crock or airtight container) for about two weeks. If room temperature in your kitchen reaches above 70°F, however, it's best to refrigerate ASAP.

Raw eggs will last four to five weeks in the fridge, but hard-boiled eggs will only last about a week.

Yes! If your maple syrup is in the pantry, you'll want to move it to the fridge. Keeping maple syrup refrigerated prevents it from growing mold, and nobody wants moldy buttermilk pancakes.

If you're unsure how long your eggs have been in the fridge, there's an easy way to tell if an egg has gone bad. Drop an egg in a bowl or glass of water. If it sinks but stands upright, it's still fine to use but it's a little older. If it floats, it's bad and you should not use it.

You might be surprised to know that you should not refrigerate onions. The chillier temperatures can cause the onions to become soft and soggy. It's best to store them in a cool, dry place (like the pantry), and they'll have a much longer shelf life.

There's no need to refrigerate soy sauce. Ever notice that restaurants keep it out on the tables? While refrigerating opened soy sauce will extend the shelf life to up to three years, it's also OK to leave out of the fridge.

Shiny apples look pretty, but you're better off choosing the organic variety, bruises and all. Shiny apples have a shellac coating placed by food producers to prevent bruising and extend shelf life.