Meat Tenderness

When heat is applied to meat, two general changes occur: muscle fibers become tougher and connective tissue becomes more tender. During cooking, actin, myosin and other muscle fiber proteins undergo changes. During heating, peptide chains composed of ammo acids (the basic components of proteins) unfold (denaturation) and then reunite in a new form (coagulation): the end result of that process is shrinkage, moisture and fat loss, and toughening of the muscle fiber. The tenderizing effect of moist heat on connective tissue results from the conversion of collagen, a type of connective tissue, to gelatin. The extent to which these changes occur in a piece of meat depends on time and temperature of cooking.

For muscles or cuts of meat with a considerable amount of collagen-containing connective tissue (e.g., the beef chuck), the toughening of the fibers is of less importance to tenderness than gelatinization of collagen. When heat is applied, the collagen is transformed into a water­ soluble gel and the muscle softens. Maximum connective tissue softening is achieved using moist heat, a low temperature and a relatively long cooking period.

Cuts of meat such as loin steaks or pork chops, which contain small amounts of connective tissue, are most tender when cooked rapidly, with dry heat and at a higher temperature. These cuts are also more tender when cooked to 145°F rather than at the well done stage because toughening of muscle fibers is minimized.

Meat can be tenderized in the home with limited success by application of food acids. Most marinades contain some form of very weak, organic acid (lemon juice , tomatoes, wine, vinegar) which tenderizes the meat surfaces. Marinades penetrate only about 1/4" into the interior of the meat, and thus contribute more to flavor than to tenderness.

Natural enzyme tenderizers are more effective in tenderizing than are acid marinades. Enzymes of vegetable origin that are used as tenderizers include papain, from the tropical papaya; bromelin, from pineapple; and ficin, from figs. These are available as powders or in seasoning compounds. Care must be taken to avoid over-tenderizing the meat (by using too much tenderizer or by allowing the meat to remain too long at the temperature optimal for enzyme activity). Individual steaks and chops may be sprayed or dipped in an enzyme solution, but use on very thick cuts of meat such as roasts does little good because the enzymes only penetrate about 1/4" into the meat surface.

Another method of tenderizing is to break or cut the muscle fibers and the connective tissues. This can be done by grinding, chopping, pounding or with the use of a special instrument which pierces the meat with multiple, thin needles (the terms, “needling” “blade tenderizing” and “Jaccarding” are used  colloquially to describe this process).  The holes made from the needles can be seen (on very close inspection) in the uncooked meat but are not visible after cooking. A version of the needle tenderizer is available for home use.  A steak macerator is used by retail stores and restaurants to make cubed steaks. Cubed steaks are made from cuts from less tender areas such as the chuck or bottom round. Sometimes steak trimmings and end pieces are formed together in a macerator to produce high-quality cubed steaks.      

Source: Lessons on Meat


Video Podcasts and Webinars

  • Grass or grain? Is there a definitively sustainable beef production system?

    03/22/2016

    The webinar examined the science relating to grass-fed and grain-fed beef in terms of sustainable... read more »

  • 2015-2020 Dietary Guidelines for Americans Update

    01/12/2016

    Kris Sollid, Registered Dietitian with the International Food Information Council and Sarah Romo... read more »

  • Meat in the Diet

    08/10/2015

    read more »

Social Media