NFS 53 1st Edition Exam 2 Study Guide Lectures 11 17 Lecture 11 February 19 I Meat Structure a Meat is made up of muscle fibers i Made up of myosin and actin ii These proteins when activated slide past each other to shorten the entire fiber and thus thicken and shorten or contract b Fat i Muscles use fat as an energy store in particular red ii Fat contributes to richness and mouth coating smoothness c Carbohydrates mostly glycogen i Some muscle tissues use glycogen a carbohydrate stored directly in the cells for anaerobic metabolism which produces lactic acid Lecture 12 February 24 An introduction to Grass based Dairy and Beef a Beef i Grain 6 12 months pasture feedlot CAFO ii Grass on pasture only b Dairy i Grain a confinement barn ii Grass come back to barn from pasture for milking II System Perspective sun rain grain grass cow milk a Grain Crop i Purchase a lot of equipment ii Buy seed other growing supplies iii Runoff is a huge problem 1 Sediment nitrogen phosphorus b Grass Crop i Perennial forage c d e f g h ii Only plant once iii Easy cheap iv Cows eat and fertilize v Cows congregate in one area thus creating management grazing Rotational grazing i Great infiltration of water into the soil ii Decreases pollution runoff iii Reverse atmospheric carbon build up Animal Health i Better digestive health 1 Lower stomach acidity 2 More beneficial microorganisms ii Less lameness mastitis iii This means a total lower monetary cost Downsides i Milk yield is lower ii Size up time takes longer iii Price for consumer is higher 1 Cow pooling a way to cut cost Buying a cow with other people and splitting it USDA Grass fed definition i Must be fed only mothers milk and forage ii Forage can be pasture or stored ie hay iii Definition is needed because producers were falsely marketing their beef iv Weakness of the definition 1 Can be confined to a pen and fed dry hay 2 Does not prohibit antibiotics or hormones USDA organic certified i No antibiotics or hormones ii Pasture Rule 2010 1 Free access to pasture 2 At least 120 day grazing season 3 30 dry food must be from pasture American Grass Fed Association i 3rd party certification ii Stricter than USDA iii Requirements 1 Fed only grass forage III IV I II 2 Raised on pasture 3 No antibiotics or hormones 4 Lives on an American Farm Health benefits of grass fed meat and dairy a Less overall fat and calories b Healthier composition of fats c More omega 3 conjugated linoleic acid d Less omega 6 e More antioxidants ie beta carotene vitamin E zinc Flavor profile a Deeper flavor b More beefy c Mineral notes d Flavor depends on environment e Cleaner earthier flavor f More lean less oily mouthfeel Cooking consideration a Pan sear the meat b Be careful not to overcook because it has less fat c Best cooked rare medium rare d Cook 70 as long as regular beef e Add moisture Meat structure Skeletal tubular muscle fibers connected together Smooth more flattened out fibers connected Cardiac spaced out tubular fibers connected by small horizontal fibers a Connective tissue i Connects individual cells and tissues to each other ii Holds muscle fibers together that organize into sheets b Protein filaments i Run through connective tissues ii Collagen 1 Found in tendons 2 Makes up 1 3 of protein 3 Hydrolyzed to gelatin in water and becomes tender iii Elastin 1 Found in ligaments and blood vessels 2 Tough c Fat i Fatty tissue or cover fat ii Marbling intramuscular fat d Bone i May help identify location on carcass e Texture and taste i Tough meat is really a resistant texture ii Tough meat can come from muscle fibers amount of connective tissue and amount of marbling fat iii Tender cuts from back of animal less active muscles Examples rib tbone wedge iv Less tender cuts from shoulder and hip more active muscles Examples blade and round bone Lecture 13 February 26 I Cuts of meat a Most tender cuts i Rib T bone or loin and wedge or sirloin b Medium tender cuts i Chuck or arm shoulder area rump hind leg area and round c Least tender cuts i Flank plate brisket neck shank ii II Tenderizing techniques a Enzymes digest proteins and cause Tenderization papain bromelin ficin Caused by general hydrolysis b Mechanical pounding grinding cubing III IV V Accomplished by breaking fibers c Acid hydrolyzes proteins such as a marinade d Salts retain moisture and break down compounds surrounding muscles which causes the release of protein e Hydration of connective tissue by cooking in moisture Storage a Best if stored below 36 F or at least refrigerator temperatures Maximum refrigerator storage is 3 5 days however ground or variety meats should be used in 1 2 days b Should be wrapped as not to absorb odors from surrounding foods Poultry a Turkey chicken goose duck Meat cookery a Dry heat used on tender cuts of meat that contain a high proportion of muscle tissue Examples roasting or baking broiling saut deep fat frying b Moist heat used for less tender cuts of meat that contain more connective tissue like collagen and elastin which soften in moisture Examples braising stewing boiling slow cooking VI Fish classification a Vertebrate versus Invertebrate b Salt or Freshwater c Lean or Fat VII Vertebrate fish with fins a Lean 5 fat in edible flesh i Examples cod flounder bluefish sole haddock pike perch b Fatty or not lean 5 fat in edible flesh i Examples eel trout salmon shad mackerel lake bass sturgeon VIII Shellfish or Invertebrates a Mollusks partially or wholly enclosed in hard shell i Examples oysters clams abalone scallops mussels b Crustaceans covered with crust like shell and segmented bodies i Examples lobster crab shrimp crayfish IX Composition a 18 20 high quality protein b Low in fat and cholesterol c Fat is most unsaturated d 30 45 omega 3 fatty acids with 8 12 being eicosapentanoic acid EPA e Fish are good sources of zinc iron and copper with marine fish being a good source of iodine X Storage a Store below refrigerator temperatures 30 F for only 1 2 days and covered tightly to prevent contamination of other foods XI Market Forms a Drawn fish entrails removed b Dressed scaled eviscerated heads tails fins removed c Steaks cross section of dressed fish d Fillets side cut off fish lengthwise away from back bones e Butterfly fillet both sides of fillet f Fish sticks cut from fillets or steaks or made from minced fish XII Cooking Finfish a Both dry and moist heat methods are used although due to delicate structure of tissues and low amounts of connective tissue dry methods are