Muscle Meats
Elastin ( effects of heat and moisture)
AKA silver skin. Found primarily in neck, shoulder and rump of land animals. When heated, it turns rubbery, shrinks and toughens. Must be mechanically removed or tenderized.
Rigor mortis & physiological changes
After slaughter, metabolism in cells interrupted, stiffening of carcass due to muscle contraction. The muscles accumulate lactic acid --> drop in pH --> ATP used up --> results in muscle contraction & permanent cross bridge in muscles between actin and myosin (actomyosin) muscle --> meat
Purpose of aging. Wet aging vs. dry aging
Aging: holding meat for a period of time (beef only), increases tenderness, improves flavor and juiciness and better browning. Wet-aging: packing into a vacuum bag under refrigeration, less shrink and trim loss, more yield. Dry-aging: hang under refrigeration for 2-4 weeks (34-38F, 70% humidity); more moisture loss --> concentrating flavor --> superior method
Role of connective tissue
Binds muscle cells together. More development of collagen in muscles used for movement. Increase in connective tissue = increase in tenderness.
Classification of poultry
Classified by age and weight; some by gender. Broiler/fryer: <13 weeks (most retail sold 6-8 weeks), 3-5 lbs, conventional supermarkets Roaster: 3-5 months, >7 lbs Cornish Game Hen: different breed cross, 5-6 weeks, <= 2 lbs Mature chickens: >10 months, best for moist-heat preparation/stewing; lots of flavor due to increase in collagen
Nutrient similarities of meats
Complete protein, B vitamins (especially B1, B2, and B3), iron, zinc, phosphorus, some copper and other trace minerals.
"Fishy" smell in fish
Deterioration of bacteria and enzymes in fish caused by trimethylanime found in phospholipid in fish fats
Inspection and Grading of fish
Finfish inspecting voluntary (based on wholesomeness of the fish and sanitary conditions). Only inspected finfish graded (appearance, texture, uniformity, good flavor, fresh odor and absence of defects.
Composition of muscle & connective tissue of meat vs. fish
Fish have less collagen than land animal meats. Collagen is broken down more easily in fish. Muscle fibers are shorter and arranged into myotomes and separated into myocomotta (flakes easier).
Labeling terminology of poultry
Fresh: never < 26F Hard-chilled: held below 26F-0F Frozen: 0F or below Percent water retained: result of washing the carcass, chilling, post-slaughter process
Inspection and grading of red meats
Grading voluntary, conducted by USDA, paid for by meat packer/processor. Prime meats have more fat content and are more valued in restaurants. Select meats have less fat and are more common in gorcery stores. Federal Meat Inspection Act makes inspection mandatory for all meat crossing state lines entering the U.S through foreign commerce. Inspectors look at animal before slaughter, the carcasses and observe the various stages of meat processing
Marbling fat and where it is found
Intramuscular fat, fat cells deposited between the muscle fibers.
Storage of fish and mollusks
Keep fish on ice to prevent rigor mortis from resolving. Purchase mollusks alive and don't suffocate. If mollusks don't close tightly, then throw out. If don't open once cooked then throw out.
Types of tenderization
Mechanical: grinding or cubing the meat Acids: break down the outside surfaces of the meat Enzymatic: proteates that hydrolyze surface proteins (papaya, pineapples, figs, etc.), pierce fork after adding to increase penetration
Collagen (effects of heat and moisture)
Most abundant type of connective tissue. When heated w/moisture, hydrolyzed into gelatin which increases tenderness on less tender cuts of meat (braising)
Cooking methods used based on amount of connective tissue
Most tender meats have the most connective tissue. Moist-heat methods are used to hydrolyze the collagen. Moderate-high, short-time dry heat methods used when there is less collagen. Carve across the grain
Safe storage and handling of muscle meats
Must be stored in refrigerator in temps. below 40F. Proper thawing: 70F or less cold running water for 2 hrs max or microwave on defrost, must cook immediately. Meats must be cooked to 160F. Whole beef, veal, lamb, pork, and ham cooked to 145F w/3 min rest. Poultry cooked to 165F.
Oxymyoglobin vs. Metamyoglobin
Oxymyoglobin: the purplish-red myoglobin is exposed to oxygen --> turns cherry red. (*nitrates and carbon monoxide used to keep in this phase. Metamyoglobin: further oxidation of the oxymyoglobin --> brown color
Biological and chemical contamination of fish and what groups should avoid them.
Parasites, Vibrio vulnificus, Norwalk virus, hepatitis A are seafood toxins. Ciguatoxin in reef fish. Red tide transferred to humans through shellfish. Scambrotoxin is allergic rxn from histamine due to fish deterioration. Pregnant women & those susceptible should avoid these fish.
Myoglobin
Pigments of color, similar in structure to hemglobin. Carries oxygen to muscle tissue. The more exercise and the older the animal gets, the more red the myoglobin is.
Nutrient Differences between red meats, poultry and fish
Poultry & fish have less cholesterol and fat (depends on species of fish and where the meat was taken from) Red meats, dark poultry and some fish are better sources of iron, zinc and other trace minerals. Marine fish are better sources of iodine.
"Warmed over flavor" in poultry and cause
Result of oxidative rancidity in UFA. Chicken has higher amounts of UFA than other meats. Results in off-flavors
Trimmable fat & where it is found
Subcutaneous fat, fat cells deposited under skin of the animal.
Inspection and grading of poultry
The Wholesome Poultry Products Act made inspection for meat across state lines mandatory. Poultry sold within state lines slightly different. Poultry inspected for wholesomeness before and after slaughter. Grading is voluntary: grades A, B, C. Graded on appearance, conformation, fleshing, and amount of fat distribution.
TSP and irradiating in poultry processing
Used as a antimicrobial agent. Irradiation used to treat uncooked poultry and reduces pathogenic bacteria
