Garlic PowderGarlic powder isn't a true substitute for fresh garlic - nothing could be - but it does have its advantages. It usually lasts for a long while and a little goes a long way when cooking, so some people buy it as an alternative to minced garlic for keeping in the kitchen store cupboard.
What Is Garlic Powder?In theory garlic powder is very simple: it's just dehydrated garlic cloves that have been ground to a powder. Some of the high quality brands you can buy are just that, pure garlic.
Not all of the brands on the market are pure garlic. Sometimes artificial ingredients are added to "improve" the colour or flavour. As always, it's worth checking the ingredients before you buy.
Sometimes garlic powder is included in other dried spice blends in the stores. The most common of these is garlic salt which is usually just salt plus powdered garlic. Obviously if you're using the powder as an alternative food seasoning in order to cut down on your salt intake, there isn't much point using garlic salt!
As with most things, if you have time then probably the finest quality garlic powder comes from making it yourself in your own kitchen. Home made usually wins out when compared with shop bought.
Powder vs FreshThe instructions on packets of garlic powder often talk about using equivalent amounts in place of fresh garlic when cooking. Personally I don't do that. Even when it's pure, I find that the powder doesn't taste exactly the same as fresh garlic. Good garlic powder can be very pleasant - but to me it is a taste of its own. For this reason I prefer to use it as a seasoning ingredient in place of salt or in slow marinades.
There's no reason not to have both fresh and powdered garlic in the kitchen at the same time.