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Lecture+16 - Lecture 16 Lecture 16 Meat Steer Steer Meat...

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Unformatted text preview: Lecture 16 Lecture 16 Meat Steer Steer Meat Meat Most expensive food consumed by Americans. Requires knowledge of meat cuts and methods of preparation to determine what cut of meat to purchase. % of Income Spent on Meat % of Income Spent on Meat Role of Meat in National Role of Meat in National Economy Livestock production linked to westward expansion of U.S. Beef as an economic commodity Livestock industry is a powerful congressional lobby Organoleptic Quality of Organoleptic Quality of Meat Depends on type and quality of meat purchased and preparation technique. Meat Meat Considered a central focus in American meal planning. – USDA Nationwide Food Consumption Surveys over the past 25 years have indicated a decline in meat consumption, particularly beef. – May be due to shift from eating meat as a whole, such as a roast or a steak, to eating it as a part of a mixture, as in a stir­fry. U.S. Per Capita Consumption of U.S. Per Capita Consumption of Pork, Beef, and Chicken Boneless Consumption Boneless Consumption Projection to 2010 Adding Fish to the Mix Adding Fish to the Mix Composition of Meats Composition of Meats Structure of Meat Meats are composed of a combination of: – Water – Muscle – Connective tissue – Adipose (fatty) tissue – Bone The proportions of these elements vary according to the animal and the part of its anatomy represented by the cut of meat. Meat Nutrients Meat Nutrients Source of complete protein Iron Zinc B­complex vitamins Fat soluble vitamins Fat – Saturated fat – cholesterol – Heme iron Dietary Sources of Iron Dietary Sources of Iron Heme Iron Heme Iron Meat Composition Meat Composition Protein—about 20% of weight – Muscle tissue—composed of muscle cells (fibers), segments contain actin and myosin which contract – Connective tissue—part of ligaments and tendons, bind muscle tissues together Collagen Elastin Reticulin—precursor of collagen Water­­~ 75% Fat­­~5% – Subcutaneous (finish) – Marbling (intramuscular) You cant trim this away Under the hide Muscle Cells (Protein) Muscle Cells (Protein) Tube­like rods or fibers tapered at both ends – Varying diameter from 1/200 – 1/1100” – Up to 2 inches long – Larger cells can be seen with the naked eye Shreds of chicken breast Texture of London broil Texture of pot roast Many nuclei Cytoplasm filled with water containing proteins, emulsified fat, fat­like substances, minerals and vitamins Grouping of Muscles Cells Grouping of Muscles Cells Muscle cells grouped together by connective tissue Tendrils of connective tissue may enter cells Heavier mass of connective tissue surrounds each bundle At ends of muscles, long ends of connective tissue join to form a tendonous mass to attach to bone. Types of Connective Tissue Types of Connective Tissue (Protein) Collagen – 3 polypeptide strands, arranged in a braid­like 3­D structure – White – Soluble in hot water – Collagen ___MOIST HEAT___> gelatin – Responsible for increased tenderness when conversion is complete – Collect as pan drippings Collagen Collagen Structure of Collagen Structure of Collagen Types of Connective Tissue, Types of Connective Tissue, con’t Elastin – – – – – – – – Yellow Strong fibers, used to support weight of the body Heat and moisture have no effect Tenderized mechanically or chemically Grinding Marinating Swissing Cutting against the grain Tenderize Elastin Tenderize Elastin Grinding meat physically cuts elastin fibers Create a tender product All ground meat products are considered tender Elastin Elastin Development and Deposit of Development and Deposit of Collagen – Deposited throughout the body – Increases with age – Increases with use (activity) – Greatest concentration in muscle groups used in locomotion and grazing neck, shoulders, front legs, back legs more collagen Development and Deposit of Development and Deposit of Elastin Strong fibers Deposit along underside of body – brisket – Short plate – flank Beef­­Chuck Beef­­Chuck Beef—T bone Beef—T bone Beef Round Beef Round Beef Sweetbreads (thymus) Beef Sweetbreads (thymus) Fat Fat Layers under hide and around organs— subcutaneous and serve as stress cushion Within and intermingled in muscles— marbling Amount of fat in cut responsible for “juiciness” and flavor of meat Fat terms Fat terms Larding – – – Piquing Purpose to make dry meat juicy Inserting long strips of lardoons through muscle Meat that is low in fat has fat added back to eat Barding – Same as larding, but small strips – Wrap cut with thin slices of fat – Usually bacon – Originally used “lard” but any fat can be used. Barded with a strip of bacon Barded with a strip of bacon Mad Cow Disease Mad Cow Disease Incidence in England ~200,000 cases Bovine Spongiform Bovine Spongiform Encephalopathy Degenerative disease affecting CNS of cattle TSE (Transmissible Spongiform Encephalopathy) – Group of brain diseases that cause sponge­like abnormalities in brain cells – Associated with accumulation of abnormal PrP in the brain PrP (Prion Protein Cellular) PrP c Naturally occurring protein found in CNS and other tissues Changes in structure results in an abnormal shaped protein that accumulates in the brain of subjects affected TSE in Animals TSE in Animals Scrapie in sheep and goats Transmissible milk encephalopathy BSE Chronic wasting disease in deer and elk TSEs in captive wild ruminants, cats, and monkeys in Europe Transmission of BSE Transmission of BSE Contaminated feed containing TSE meat and bone meal. Scrapie infested sheep or cattle. Practice of feeding entrails of slaughtered animals to live animals. TSE in Humans TSE in Humans Creutzfeldt­Jakob Disease (CJD) Fatal Familial Insomnia Gerstmann­Straussler­Scheinker Disease Kuru nvCJD – Neurological disease which usually affects people over 55 years of age U.S. Safeguards for Mad Cow U.S. Safeguards for Mad Cow Disease Import of beef from Great Britain banned since 1985. Since 1989, ban extended to all beef products, including tallow and bone meal. Practice of feeding ruminant animal remnants to cattle banned since 1997. 2004 2004 “On 1/19/04 USDA completed selective depopulation operations on the facility in Mattawa, Washington.” USDA USDA investigation into 81 cows that came from Canada. – 1 of 81 was infected with BSE March 23, 2006 March 23, 2006 USDA reports that the incidence of Mad Cow Disease has dropped worldwide. Incidence has been dropping 50% per year over the last 3 years In 2005—474 animals died worldwide, compared to 878 in 2004 and 1646 in 2003 5 people died of CJD, all in Great Britain March 14, 2006 March 14, 2006 Third bovine in the U.S. was euthanized due to Mad Cow disease Alabama Examination of the teeth appear to suggest that the animal was more than 10 years old, older than the ban of scrapie in the U.S. in 1997. Sources of Meat Sources of Meat Domesticated animals used for food – – – – – Beef (bovine) Veal (bovine) Lamb (ovine) Pork (porcine) Game – Note, poultry is not classified as meat by USDA Beef Beef Produced primarily from steers and heifers of Angus or Hereford cattle Large 1000 lb.+ on hoof, ~600 lb. trimmed Usually slaughtered between 30­42 months of age. Red meat, hard fat—white to yellowish­white Veal Veal Young bovine Usually male offspring of milking cows, but some cattle are used Veal is less than 3 months of age – Light pink meat, very little fat, small muscle groups, little connective tissue – Tends to fall apart when prepared Calf is 3­8 months Baby beef is 8­12 months. Lamb Lamb Most imported from Australia or New Zealand – Lamb is less than 14 months of age – Over 14 months, mutton Dark red meat, very hard fat Flavor strengths with age of animal Tenderness decreases Loin Lamb Chop Loin Lamb Chop Pork Pork Hogs or swine Grey­pink meat, soft, greasy pink fat – Barrow, gilt, sow, boar, stag Marketed between 10­12 months usually. March 27, 2006, Star Ledger March 27, 2006, “This sounds fishy—pigs with omega­3” U of Pittsburgh School of Medicine, U of Missouri­Columbia National Swine Resource and Research Center and Mass General Hospital collaborated Pigs have better cardio­vascular function and live longer Created a gene, fat­1, which creates an enzyme that converts omega­6 fatty acids to omega­3 fatty acids. Finding these hogs in the food supply is a long way off—or maybe not, since FDA is considering Fresh Ham Fresh Ham Federal Meat Inspection Act Federal Meat Inspection Act Mandatory inspection for wholesomeness of meat from domestic sources Imported meats subject to same standards Conducted by USDA—FSIS – – – Prior to slaughter (with accompanying documents) Carcass—at various stages of handling Package materials and labeling USDA Symbol USDA Symbol Circular symbol affixed to inspection certificate and run along carcass over finish fat Meat Inspection Meat Inspection Meat Legislation, con’t Meat Legislation, con’t HACCP Rule 1996 – Identification of hazards – Setting critical limits – Describe procedures at steps in meat handling – Mandatory testing for E. coli Quality Grade Quality Grade Voluntary, but most likely done, since meat must be inspected Major factors – – – – Color of flesh, bone Grain of meat Texture Fat distribution and amount Finish marbling USDA Prime – heavy marbling USDA Choice – moderate marbling USDA Select – spotty marbling Amount of Marbling will differ Amount of Marbling will differ Yield Grade Yield Grade Amount of edible tissue from a cut of meat after the application of heat, removal of bone and fat Highly variable USDA Grades 1­5 predict the amount of useable meat available from a carcass Yield Grades Yield Grades Aging Aging A process which allows for enzymatic activity to breakdown connective tissue (to tenderize) Improves flavor Hanging losses – Dry—carcasses are hung in refrigerator for 2­6 weeks – Fast—70o F and 90% humidity for 2 days (UV lights control microbial growth) – Cryovac—(vacuum packed)—carcass cut to primal or fabricated cuts and wrapped in heavy, shrink­wrapped plastic Increased shrinkage Tenderizing Tenderizing Mechanical processes Marinade – Oil/acid mixture (3:1) – Score, cube, pound, grind, slice thin (diagonal) Use of enzymes – MSG Commercial meat tenderizers Salts – Papain, from papaya; sprinkled on surface – K, Ca, or Mg—retain moisture and breakdown protein Purpose of Meat Preparation Purpose of Meat Preparation Make microbiologically safe – Clean cutting board, knife – Personal hygiene – Hot soapy water Increase palatability – Improve tenderness by reducing connective tissue – Improve flavor by developing extratives, lactones, S­ containing compounds, mercaptans and pyrazine Heating of Meat Heating of Meat Coagulation of protein at 160­175o F Denaturation (moisture loss) 140o F Both processes occur simultaneously as heat is applied Water is lost – Shrinkage Varies by cut Heating temperature (low is best) Characteristics of denatured protein Characteristics of denatured protein by heat: Change in characteristics of meat – – – Increased firmness Loss of solubility Straightening of coiled proteins and cross­linkages across the straight chains that are formed High heat increases firmness (almost solid texture) Moisture is more readily expelled at high temperature, causes dryness Protein denaturation Protein denaturation Heat application causes gradual process – – – – – Visual changes occur between 122­149oF Heme pigments and other pigments remain pink Meat is very juicy Tender Collagen begins to alter at rare stage – At high temperatures and longer heating: cross­ molecular bonding increases firmness Color Change in Cooked Color Change in Cooked Meats Cooking Loss Controls Cooking Loss Controls Cooking loss = shrinkage All meat shrinks, but can be controlled Factors effecting shrinkage: – Amount of fat – Heating temperature – Degree of doneness Degree of Doneness Degree of Doneness Determination of protein denaturation resulting from the application of heat. Determined by: – Time/weight—table of minutes per pound of heat applied – Color changes—rare= red interior, medium = pink interior, well done = brown interior – Internal temperature­use meat thermometer, inserted in thickest part of meat cut, away from bone and fat – Touch—firmness of meat, need to be well experienced. Effect of heat on fat Effect of heat on fat Melts (renders on heating) – Contributes to juiciness of meat by preventing surface evaporation of water – Improved by basting The higher the temperature, the closer the source of heat, or the longer the heating time will increase melting Melted fat in conjunction with some evaporation produces crispness Fat­soluble flavors are released Flavor Development Flavor Development Heating develops flavor – – – – Alters amino acids into flavorful products Free fatty acids (major source of meat flavor) Carbonyl fractions improve aroma The greater the heat, the more flavor Well done meat is most flavorful – Flavor develops for the 1st 3 hours of heating, then declines Protein Hydrolysis Protein Hydrolysis Most important in moist heat applications – Hydrolysis of collagen to gelatin increases tenderness of meat – Increases fragmentation of molecules to produce moisture loss through structural breakdownmeat may fall apart Dry Heat Methods of Meat Dry Heat Methods of Meat Preparation Application of heat to meat without added moisture to denature or coagulate proteins. As heat is applied, collagen unwinds to gelatin in the presence of the moisture in the meat itselftenderizing the meat Muscle tissue becomes firm Cooking losses occur. Roasting Roasting Used for larger cuts of meat (2 lb. +) Boneless or bone­in – Place roast (from refrigerator) on rack in shallow roasting pan – Insert thermometer into thickest part, not touching bone or fat – Do not add water and do not cover – Roast to 5 to 10 degrees below desired degree of doneness – Allow roast to stand for 15 to 20 minutes before carving. Internal temperature will continue to rise during standing time. Beef Roast Beef Roast Broiling Broiling Used for ¾ ­ 1” thick cuts Boneless or bone­in (steaks, chops) Radiant energy source (direct flame, glowing electrical coil) positioned 2­6” from meat. – Place meat on broiler pan (slotted to allow fat escape) – Broil for half the recommended time – Turn and continue to desired degree of doneness – Season, if desired Broiled (London Broil) Broiled (London Broil) Grilling Grilling Used for thinner cuts, 1/2 “ or less (patties, minute steaks) Add fat to pan or grill surface Grill for half of recommended time Turn, continue grilling Internal temperature can be checked using instant read thermometer Burgers on the Grill Burgers on the Grill George Foreman Grill George Foreman Grill Panbroiling Panbroiling Used for cuts less than ½” Similar technique to grilling, but fat is removed – – – – – place meat in preheated, nonstick pan Do not add fat or water Do not cover Pour off fat as it accumulates Turn meat once Stir­frying Stir­frying Partially freeze meat to ease slicing Cut into thin, uniform slices, strips, or pieces Cook meat and vegetables separately, then combine – Stir­fry meat in about a tablespoon of hot oil or use nonstick spray – Continuously turn meat with a scooping motion – Combine cooked meat with vegetables and serve Stir Fry Stir Fry Deep Fat Frying Deep Fat Frying Used for cubed pieces of meat or poultry Fat is preheated (400o F or more) – Dry meat is added – Continue heating until pieces are golden brown – Remove from heat and drain. Fried Chicken Fried Chicken Moist Heat Methods of Meat Moist Heat Methods of Meat Preparation Used for cuts which contain large amounts of collagen Water present in the cut is insufficient to fully unwind collagen to gelatin Water is added to the recipe to facilitate conversion and the mixture is heated. Usually, time increases Braising Braising Used for less­tender cuts Meat is browned in a small amount of fat (may be coated with flour) Small amount of liquid is added Cover and simmer on range­top or in oven Simmered until fork­tender Braising medium is consumed with meat – – – Pot roast Beef stroganoff Veal marsala Beef Pot Roast (Braise) Beef Pot Roast (Braise) Stewing Stewing Similar to braising More liquid is used Liquid may or may not be thickened – Used to prepare soups, stocks – Long­time heat application Beef Stew in a Crock Pot Beef Stew in a Crock Pot Steaming Steaming Direct meat exposure to moist heat Steamed in a pressure cooker or a tightly covered pan. Covered in aluminum foil or cooking bag. – Meats “roasted” in bag are steamed, a moist heat application Ham in “Roasting” Bag Ham in “Roasting” Bag Microwaving Microwaving Difficult to complete accurately due to differences between microwaves and cuts of meats. Choice of power setting is key to success Overall, meat is not browned, unlessmicrowave has a browning unit, or a browning tray is used. – Use 50% (medium) or 30% (low) for larger cuts – 100% power (high) evaporation decreased juiciness Meat Preparation Meat Preparation Select method of meat preparation appropriate for the cut Tender vs. less tender Dry heat methods – Beef—tender cuts found along the spine; the rest of the carcass is less tender – Veal, pork, lamb—entire body is tender; animal is young – Used for tender cuts – Used for less tender cuts, but may be used for veal, pork and lamb to prevent dryness Moist heat methods Storage of Fresh Meat Storage of Fresh Meat Extremely perishable—short shelf life – Refrigeration (33o F) wrapped loosely, maximum 2 days, ground meat 1­2 days – Freezer (0o F) tightly wrapped, up to 12 months – Leftoversrefrigerated 2 days Processed Meats Processed Meats All meats changed from original “fresh” state to another form, resulting is different characteristics Curing Smoking Purpose: – – – Preservation Enhance flavor, texture Provide convenience Curing Curing Meat is rubbed or injected with salt, sugar, spices, etc. Changes flavor, texture, color Smoked Meat Smoked Meat Injection of liquid smoke Hung in a room with a smokey flame (smokehouse) Usually accompanies curing Treated with sodium nitrite to prevent clostridium botulinum growth. Varieties of Processed Meats Varieties of Processed Meats Major processed meat sausage, made from pork Ground meat­containing recipe enclosed in a casing – Natural or artificial – Artificial not edible, removed in factory to produce “skinless” sausage – Contains varying amounts of water, emulsifiers, cereals, starches, etc Meat and meat by­products ...
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