Contrary to popular belief, almost none of a marinades flavoring penetrates into the center of meat. However, a 2010 article in the Journal of Food Science documented that salt and glutamates do. Glutamates are naturally occurring flavor enhancers. As a result, there are three crucial ingredients in a marinade – salt, tomato paste, and beef stock.
Salt – Not only does salt penetrate foods to flavor the interior, it also swells and dissolves some proteins allowing them to hold more juices.
Tomato Paste – This marinade ingredient is high in glutamates that will significantly increase the savory flavor. Just 3 tablespoons will help a lot.
Beef Stock – Many commercial beef stocks contain yeast extract. Check the ingredients list. Yeast extract is high in glutamates and nucleotides, both of which are flavor enhancers. Only 1/3 cup can have significantly impact.
Glutamates were discovered in 1909 by Kidunae Ikeda, which he extracted from seaweed. This substance has been found to stimulate taste receptors on the tongue and the sensation was named umami (sensation number five after salty, sweet, sour, and bitter). The English translation of umami is “delicious” or “savory.” In addition to tomato paste and yeast extracts, soy sauce is very high in glutamates and is included in many marinades.
Many items are marinated for a period of only 2 hours or less to thoroughly coat the meat’s surface. Marinades penetrate very slowly. A liquid marinade such as described above should be placed in a zip-top bag with the meat. Zip the bag almost closed, expel as much air as possible, and zip the bag fully closed. Marinate refrigerated for 1 to 4 days to allow the seasonings to penetrate.