Why we use marinades? Principally there are two reasons. One is to add flavor, and the other is to tenderize. Usually, we are trying to do both.

It’s worth bearing in mind that marinating is a cooking process, even though heat is rarely applied. The importance of recognizing this is that, like any other cooking process, you can overdo it.

It’s not just a case of putting the meat or fish in a sauce and leaving it there until you are ready to use it. Many of the fruit juices we use in marinades, such as lemon and pineapple, contain enzymes that break down proteins. In essence, what they do is digest them.

Leaving meat in them for too long would result in an unpalatable mush. If you want to try this for yourself, leave a piece of pork in fresh pineapple juice overnight and then see what happens when you cook it.

You probably won’t like the result.

It’s a tragedy that although we are killing our animals at an earlier age in order to satisfy the demand for fresh meat, the end product still tends to be tough.

There are good reasons for this and it is useful to have a working knowledge of them if only to avoid potential disasters.

It is not, as some cooks would have you believe, simply a matter of finding a butcher who will take the trouble to discuss your needs with you, if indeed such a person still exists outside of the more fanciful cookbooks.

Our meat is tough because it started out that way. And here’s why (if you are squeamish, skip this section):

When an animal is killed its muscles (protein) go into spasm caused by the injection of the well-known fight or flight chemicals released by the brain.

Under normal conditions, that is to say in the natural world, this would be followed by rigor mortis setting in, followed by a gradual relaxing of the proteins back to their normal state.

However because of the speed at which the slaughter and preparation of carcasses is carried out, this vital, natural step is rarely if ever completed. The animal is killed, cooled and frozen in one continuous process.

The result is toughened proteins.

A butcher who hangs his meat can, to some extent, reverse this effect. If you ever find one, hang on to him for dear life. You have found a rapidly disappearing treasure.

The alternative is to use marinades.

Marinades can be wet or dry and you can add just about any flavor you desire to them.

When a marinade is liquid, the base is usually acidic. As I said earlier, this may be fruit juice, but wine, vinegar or even beer may also be used. As a matter of fact I know of one cook who uses Coca-Cola.

If it marinades meat, just think what it’s doing to your insides.

Steeping in the marinade may take anything from a few minutes to several hours, and even overnight in the refrigerator.

Source: http://www.pinoyrecipe.net