• Develop or improve flavour, colour, aroma.
• Make it delicious and appetising to eat.
• Make it more tender.
• Make it easier to digest.
• Make it safe to eat - kill any harmful bacteria it may have picked up during handling.
In the process of cooking many chemical changes occur, affecting the appearance, taste and texture of meat.
How meat changes during cooking
• Muscle proteins shrink and moisture is lost - As meat is heated, muscle proteins coagulate and shrink, squeezing out water. The longer you cook meat, the more water is forced out.
• The loss of juices through drip, evaporation and cook-out (along with its marbled fat content) determines the meat’s juiciness, the amount of shrinkage and thus the final cooked weight or portion yield.
• Prolonged cooking, or overcooking, results in meat that has lost so much moisture that it becomes dry and tough to eat.
Heat affects the pigments and changes the colour of meat. The red colour of uncooked beef changes to light pink, and finally to a brown/grey shade as the 'degree of doneness' increases.
Connective tissue softens
During long, slow cooking, some of the connective tissue softens, and gelatinises.
Fat melts, browning occurs and flavour develops
Heat causes fat to melt. Slightly browning fat develops flavour, the more you brown it, the more flavour is developed.
Searing develops flavour
• Searing or browning the outer, lean surface of meat, usually at a fairly high temperature, develops flavour and colour through caramelisation. It is an important step in several cooking methods, producing tasty meat.
• The myth about searing. Searing meat does not seal in the juices.
• A browned surface will not stop the loss of juices from meat as it cooks. As meat is heated, bundles of muscle fibres contract and force out moisture, especially from cut surfaces.
• The sizzle you hear when meat hits the hot pan is water turning to steam. Of course melting fat can sizzle too. Lean meat, totally trimmed of all visible fat, sizzles and spatters as its juices evaporate. And the longer it cooks, the more water it loses.
• When cooking meat, sear it to a good brown colour to improve appearance and flavour, and keep in mind that overcooked lean meat will be dry meat, and therefore not as good to eat as properly cooked lean meat, which is succulent and juicy.
• It goes without saying the best way to ensure the meat you cook is tender is to choose a cut you know to be tender, from a reliable source. By selecting Quality Mark meat from from your butcher or supermarket you are guaranteed meat which is lean, tender and safe to eat.
• It is also true that meat toughened during processing can never be made edibly tender.
However, less tender cuts can be made more tender by the following means:
• Acids - Marinades containing a mild acid ingredient such as lemon juice, wine or wine vinegar help to tenderise meat. The meat may be soaked in the marinade for several hours or days in the chiller. The use of a tenderising marinade is more effective on thinner cuts of meat.
• Enzymes - Some raw fruits contain protein-splitting enzymes, which act on raw meat to tenderise it. Examples include paw paw, kiwifruit, pineapple and figs. The enzymes break down and soften muscle tissue. Mashed raw fruit, liquid or powder may be spread over the meat, or mixed with other marinade ingredients to coat the meat, some time before cooking.
• The tenderising effect acts mainly at the surface, so a marinade or powder works better on small, thin cuts of meat.
• If left too long on raw meat, marinades containing these tenderising enzymes spoil the texture of meat, causing it to become mushy on the surface. Note: not all marinades have a tenderising effect. Many marinades have no acid or enzyme ingredients and are used simply to add flavour and colour to the meat.
Blade or mechanical tenderisers
• Mincing, chopping or grinding - Meat is put through a chopper, mincer or grinding machine to break up connective tissue and muscle tissue into small pieces.
• Batting out, or hammering - Meat is pounded with a meat mallet (the mallet may have a rough, toothed surface) to break down muscle and connective tissue. This method is used for individual portioned cuts, steaks or schnitzels, not whole joints.
• Cutting or needling by machine - Steaks can be tenderised using a revolving machine with tiny blades, which make very fine cuts in the meat, breaking up less tender tissue. This may be used on boneless beef steaks such as topside, silverside, thick flank or blade.
Dry and moist methods of cooking beef and lamb
There are two basic types of meat cookery:
• Dry heat methods.
• Moist heat methods.
Dry heat methods do not use liquid, but can use fat or oil. Dry heat suits tender or medium-tender meat cuts.
Dry heat methods include:
• Grilling (includes fan-grilling, pan-grilling, barbecuing).
• Shallow frying (pan-frying, sautéing, stir-frying).
Moist heat methods use liquid, and are suitable for less tender meat cuts.
Moist heat methods include:
• Braising (includes casserole cooking), pot-roasting, stewing.
• Poaching, simmering.
• Steaming, pressure-cooking.
Research has shown that the method of cookery - moist heat versus dry heat, or slow versus fast cooking - can have a dramatic impact on the ultimate taste and tenderness of beef and lamb.
Since different cuts of beef and lamb vary in composition (eg some having much more connective tissue than others), it is important to choose the cooking method which is suited to the cut to give the best results in the final dish.
The cooking method you use depends on:
• The natural tenderness of the meat cut.
• The amount and type of connective tissue.
• The leanness of the meat.
• Size and thickness of the cut of meat.
Meat cuts with a lot of connective tissue are the tougher cuts that need moist heat and longer, slower cooking to make them tender. But not all connective tissue will become tender.
Two main components of connective tissue are collagen (white) and elastin (yellow).
Collagen will become soft, tender and gelatinised, so long as a slow, moist cooking process is used.
Elastin is very tough tissue that will not become tender with cooking. Heat makes it shrink and harden. It is important to remove tough elastin tissue before cooking to help to reduce the level of toughness in some cuts.
Cuts with large amounts of collagen and elastin
Shank, shin and shoulder cuts of beef and lamb contain collagen and elastin. They should have visible connective tissue cut out, and be cooked by slow, moist heat to gelatinise the collagen.
Cuts with less collagen
Meat cuts such as fillet and striploin contain little connective tissue so suit dry heat cooking methods such as grilling, or searing and short high-temperature roasting.
Dry heat methods
Meat is cooked uncovered, in hot air, in an oven. Meat may also be roasted revolving on a spit over a fire.
Quick cooking by direct heat from a gas flame or an electric element. Meat may be placed under or over the heat source.
Barbecuing: Meat is cooked on a grid or spit over glowing coals or gas flame.
Cooking in a multi-function oven using radiant heat from the grill (upper) element and heated air circulated by a fan. A thermostat controls the temperature and the oven door is kept closed. Suitable for tender grilling cuts and some roasts
Meat is cooked on a pre-heated heavy, dry frypan or ridged iron grill pan (griddle pan), or metal hot plate. This is not frying. The cooking surface may be lightly greased, or the meat brushed with oil before cooking, but no further fat is added. Any fat drippings should be poured off as they accumulate. The meat is cooked uncovered.
Pan-frying (shallow frying):
Meat is cooked in a small amount of hot fat or oil (usually about 3-12mm depth), in an uncovered pan. A suitable method for thin cuts of tender meat.
"Sauté" literally means "to jump". Small pieces of food are tossed (either by shaking pan or using a spatula or similar utensil) as they cook in a little hot oil or fat in a sauté pan (like a frypan but slightly deeper). A suitable method for thinly sliced, small pieces of tender meat. A sauté may be finished with a sauce cooked in the pan.
Finely cut food rapidly stirred and tossed as it is fast-cooked in a little hot oil, usually in a wok, over high heat.
Food cooked by being immersed in hot oil or fat.
Moist Heat Methods
Meat is first browned in a minimum of fat or oil, then cooked gently with vegetables and a small amount of liquid in a tightly covered pot or casserole on the stove top or in the oven. Used for serving-sized pieces of meat as well as for larger cuts.
The term used for larger cuts or joints of meat cooked as for braising, but without any (or with barely any) liquid. A good method for less tender roasting cuts such as fresh beef silverside, topside and chuck roasts.
Stewing or Casseroling:
Meat cut into small pieces or cubes is cooked at a low temperature or gentle simmer in liquid, usually with vegetables, in a covered pan on the stove top or in the oven. The meat may be browned first.
Gentle cooking in liquid just below boiling point so that the surface barely ripples. Meats for simmering may be cut small, or in large pieces, e.g corned beef silverside.
Food is cooked very gently in liquid below simmering point. Liquid is hot but should not exceed a mere tremble, ie less movement than simmering.
Pressure Cooking: Cooking in liquid and steam under pressure, which increases temperature and reduces cooking time to about one third of normal time. A suitable method for less tender meat cuts, which normally need long, moist heat cooking, e.g ox tongue and beef shin.
Methods combining moist and dry heat
Microwave cookery is electro-magnetic. It is neither a dry nor moist technique, but the microwave oven can be used to roast, simmer, braise and casserole meats. However, it gives different results from conventional cooking methods and it is not always a time saver. Generally, meat cooks better, and more evenly, at lower power settings. Size and shape of the meat cut affect evenness of cooking and the time required.
This is not true roasting as the meat is enclosed, either in an oven-bag or covered roasting pan, thus trapping in some steam, and cooked in the oven
A variation is fry pan "roasting", eg small lamb leg cuts are first browned in a hot fry pan. Heat is then reduced, the lid put on, and cooking is completed.
Information supplied by the New Zealand
Beef and Lamb Marketing Bureau.