Posted by Eric Troy on 05 Dec 2013 17:51
The basic definition of a marinade is a seasoned liquid that you soak meat to enhance its flavor and/or texture before cooking. This can be a cooked or uncooked liquid mixture. More specifically, marinades usually use some kind of acid, such as vinegar, wine, or lemon or lime juice. The acid helps break down the connective tissue in the meat, so it will be more tender once cooked.
At least, we have always been told that acid helps tenderize the meat. In reality, it could not really alter the overall texture of the meat that much since it is only really affecting the outer surface, unless you used an overwhelming amount of acid and then soaked it for a very long time. Yes, acid can help break down protein bonds, but a little acidification of the outer surface of the meat is not going to turn a tough piece of shoulder meet into something akin to filet Mignon. The acid might help to deliver some of the flavor from the seasoning you use, and they give a tang, so it's more the flavor of the meat that is changed and a tastier piece of meat can be perceived as more tender.
Another school of thought says that, since the acid breaks down the fibers on the surface of meat, cells collapse and thus pack more tightly together, resulting in tougher meat. This is mentioned in several recent and popular food science books. Peter Aitken, in his book Kitchen Myths1, even claims that this "tightening" of proteins will squeeze out the moisture in the meat. These high thinkers fail to explain how they can justify a marinades surface action not being deep enough to tenderize the meat, but deep enough to toughen it significantly and squeeze out the water. It could be that some people mistake a "firmer" feel with toughness. A cooked steak feels firmer to the touch than a raw steak, but a properly cooked steak is by far more tender than a raw one. There may be, as is often the case, simply a tendency to over-sell their point. All in all, don't expect acid to significantly alter the tenderness of meat, but that doesn't mean you can't add it for the tangy taste.
Some will insist that marinades must contain oil but unless you are making a stable emulsion with the oil and water, adding oil doesn't really do anything. The only reason to think that oil and water should be in the marinade is because some spices are water soluble and some are fat soluble, but if the oil remains suspended in the water as large globules, or droplets, the fat soluble spices will not be affected much. Some also think that oil will help the marinade cling to the meat, will keep the meat from sticking to the grill or pan when cooking, and will help "lock in flavor" but again, the fat droplets are not really going to coat the meat if they are suspended in water. If you throw such a piece of meat onto a grill, all you're really going to accomplish is flare-ups from the oily water dripping into the fire. If you want oil on the meat, you would still need to pat it dry and coat it with a bit of oil before grilling.
Meat marinating before grilling.
Meat marinating before grilling.
So marinades can contain oil, and they can (usually do) contain acids, but it is not required. Therefore, a marinade is basically a seasoned liquid that usually contains and acid. If you want oil to be an integral part of your marinade, then you'll need to use an emulsifying agent to create an emulsion. Otherwise, the oil is just going to float on top, not doing much of anything.
Origin of the Word Marinade
However, originally, marinades were really just salt water, which helped to preserve the meat or fish, and of course, imparted flavor though the salt. sometimes, sea water was used, or aqua marina. It was sea water which led to the word marinade, which derives ultimately from the Latin word for the sea, mare. We also get the words marine, and maritime from this root. The verb form of the word marinate, actually appeared in English in the early 17th century, earlier than the noun marinade, which did not appear until the early 18th century. Some sources contend that the word may not have originated directly from the sea water connection but via the French word mariner or the Italian word marinare. The French mariner means "to pickle," and the Italian marinare means "to marinate." Both these word, however, refer to similar practices, since the primary purpose was to preserve or pickle. No further cooking was necessarily done. Gradually, the picking or preserving process was changed to a flavoring and tenderizing process.
So what is the most surprising fact about marinades? The more people try to debunk myths, the more myths are created and most everything you read about marinades except "they deliver flavor" is basically a myth.
Some myths about marinades
Besides the "marinades must contain oil" thing, which I believe to be a myth, there are a number of mistaken beliefs about the purposes and affects of marinating meat. Marinading vegetables is a different subject.
- Marinating makes meat more juicy
Marinating, unfortunately, does not make meat more juicy. If anything, it lessens the meat's ability to retain moisture by breaking down the connective tissues before cooking. Still, the flavor and tendernous that can be achieved with less, well, flavorful and tender cuts, can be well worth it.
- Marinating is superior to a dry rub
Marinating is only superior if it helps a cut of meat in a way that a dry rub cannot, and this is mostly in the area of imparting flavor. With a dry rub, there is less penetration and the flavor is more in the crust itself, although a dry rub does add flavor to some extent, to the meat itself.
Some, of course, believe a dry rub is always superior. Again, it depends on the cut of meat. You should not need to marinate a prime steak, in which case a dry rub may be the perfect choice. But then again, a prime cut of steak doesn't need much help. Sometimes, both bringing and dry rubs are used (brining is basically salt water with some sugar), and this can really deliver a flavor bomb, as a salt and water solution can penetrate deeper than a marinade. For tougher cuts, it is the cooking method, ultimately that tenderize the meat, but this also means a very cooked result, which is all the more reason to deliver as much flavor to the end result as possible. Which is superior, marinades or dry rubs, may never be truly decided, but I personally tend to fall on the side of dry rubs, but a brine followed by a dry rub is the ultimate, in my personal opinion.
This leads us to a connected myth. Salting, and by extension, dry rubbing, before cooking, will dry out meat since salt leaches the moisture out. Salt can definitely leach out moisture but the small amount used on the outside of meat will have little effect on the overall moisture content. Presalting tends to give a more well-rounded flavor. However, salt does draw forth a little bit of moisture to the surface, and this can interfere with the browning of a steak, pork chop, etc. A dry rub solves this problem since it creates it's own "crust" and there is usually some kind of sugar that helps with carmelizaton of the surface. If you only want to use salt, and you prefer to pre-salt, all you need to do is to avoid salting to far in advance and letting the meat sit. Pat your meat very dry, and salt the last second before cooking on a high(ish) heat, assuming it's a nice cut of steak, and not something like chuck or round. What little water that comes to the surface at that point should quickly evaporate and the browning should proceed nicely. However, if you're using a pan and not a grill, don't overcrowd it! If too much water comes from the meat in an overcrowded pan, you'll be steaming your meat.
- Poking holes or injecting helps a marinade penetrate throughout the meat
This practice of poking holes or injecting the marinade into the meat with a syringe doesn't really do much, although it was all the rage for a time.
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