MEAT PT 1

Question 1

define meat

Answer 1

skeletal muscles of mammals; may also include organs and glands and technically excludes flesh of non-mammals (poultry and flesh)

Question 2

whats the problem with beef cattle lymph nodes

Answer 2

undesirable parts of cattle get grinded up and spreads; product has more H2O and surface area; quality lower

Question 3

whats meat composed of

Answer 3

water, muscle tissue, connective tissue, adipose (fatty) tissue + sometimes bone

Question 4

do proportions of meat composition vary according to animals source and cut of meat

Answer 4

yes

Question 5

what does muscle tissue structure

Answer 5

bundle of muscle fibers, myofibril (contractile unit), muscle (muscle cell); wrapped into membrane and filled with liquid

Question 6

what is each muscle fiber (cell) surrounded by

Answer 6

outer membrane called sarcolemma

Question 7

what is each muscle fiber cell filled with

Answer 7

cellular fluid called sarcoplasm that contains thousands of myofibrils

Question 8

what do smaller + more numerous muscle fibrils result in

Answer 8

smaller muscle bundles, which creates delicate/velvety meat

Question 9

what are the contractile units of muscle

Answer 9

myofibrils

Question 10

what are fibrils separated into units called

Answer 10

sarcomeres

Question 11

what are sarcomeres bordered by

Answer 11

Z-lines

Question 12

what proteins do sarcomeres contain

Answer 12

actin and myosin

Question 13

describe actin + what minor proteins it contains

Answer 13

thin filament; contains tropomyosin (stabilizes actin structure) + troponin (contains Ca-binding protein)

Question 14

describe myosin

Answer 14

thick filament

Question 15

what initiates contraction

Answer 15

nerve impulse

Question 16

what happens when Calcium ions are released into sarcoplasm

Answer 16

bind to troponin, moves tropomyosin so myosin can bind; actin and myosin form actomyosin cross-links and myosin pulls actin towards center and the sacromere shortens

Question 17

describe relaxation of muscle contraction in three points

Answer 17

nerve impulse stops when Ca is pumped out of sarcoplasm; actin myosin cross-links break; sarcomeres return to original length

Question 18

whats rigor mortis

Answer 18

“stiffness of death,” within 24 hours of slaughtering, muscles enter temporary stiff state (reverses after 1 - 3 days)

Question 19

what happens to blood flow during death

Answer 19

stops blood flow, no O sent to cells, which enter anaerobic glycolysis at last resort to make ATP; glucose turns to lactic acid and pH is decreased

Question 20

what happens when glycogen stores are used up

Answer 20

no more ATP, so actin and myosin cannot dissociate which causes maximum stiffing (aka stuck in contracted state)

Question 21

what happens during gang (holding meat after slaughter)

Answer 21

endogenous enzymes degrade sacromere framework, which makes tenderness increase

Question 22

are pH and moisture retention correlated? how does this impact meats

Answer 22

yes; pH decreases when cell enter anaerobic glycosides so moisture retention decreases during rigor mortis

Question 23

are glycogen levels in animals before they’re killed important

Answer 23

yes

Question 24

what happens to glcoygen levels when animals are kinda at rest

Answer 24

go up before kill which contributes to quality

Question 25

what does the decrease in pH do

Answer 25

decrease in ph from lactic acid accumulation influences meat quality

Question 26

what leads to water loss

Answer 26

decreased microbial growth

Question 27

whats water holding capacity (whc)

Answer 27

the ability of a matrix to physically entrap water; decreases at pH approached during rigor mortis

Question 28

describe pH and meat quality

Answer 28

if pH too high. microbial growth will occur and if pH too low, there will be too much water loss; its important to maintain optimum pH to retain quality; if pH is not in right range, meat won't hold water

Question 29

describe the composition of meats

Answer 29

connective tissue, with collagen, elastin, reticulin

Question 30

whats connective tissue

Answer 30

mixture of proteins and polysaccharides that act as glue and hold muscle cells together

Question 31

whats collagen

Answer 31

most abundant CT protein; tough and fibrous but softens upon heating; has unique triple helix structure held together by H bonds and covalent cross links

Question 32

whats elastin

Answer 32

protein in CT; has elastic properties

Question 33

whats reticulin

Answer 33

protein in CT; forms interlace around muscle cells for support

Question 34

how do the proteins and polysaccharides in CT form a glue

Answer 34

by forming covalent bonds

Question 35

what happens to meat composition as animals age

Answer 35

2 things: collagen content increases + more covalent cross-links are formed within collagen helixes (which leads to toughening)

Question 36

what happens to tenderness as animal age decreases

Answer 36

tenderness decreases

Question 37

describe tougher cuts of meat from older animals

Answer 37

less expensive and require slow, moist-heating at low temps to hydrolyze collagen to gelatin

Question 38

whats adipose tissue

Answer 38

fat serves as insulation and padding for sensitive organs; cover fat + marbeling

Question 39

whats cover fat

Answer 39

appears on outside of meat

Question 40

whats marbling

Answer 40

intramuscular fat seen as white streaks; well marbled beef more expensive + higher quality; contribute to flavor and jucness

Question 41

what does marbling depend on

Answer 41

animals, diet, lifestyle, etc

Question 42

what does fat content depend on

Answer 42

animal genetics, age, diet, exercise, cut of meat

Question 43

whats Kobe beef

Answer 43

special grade of beef from wagyu cattle

Question 44

what are bones used for

Answer 44

used to identify meat cuts

Question 45

what is bone marrow

Answer 45

soft fatty material in the center of bones; valued food in many cultures and can provide flavor to soup

Question 46

describe antibiotics in composition of meats

Answer 46

given to ensure health and promote growth; may contribute to development of antibiotic-resusttant bacteria

Question 47

describe hormones

Answer 47

given to encourage rapid weight gain; reduces production cost; concerns over safety of residues in human health and environment

Question 48

whats organic beef based without

Answer 48

antibiotics and hormones

Question 49

whats the color of meat primarily from

Answer 49

very important; from pigment-contains protein myoglobin

Question 50

whats the pigment portion of myoglobin

Answer 50

heme

Question 51

what happens when meat is exposed to oxygen

Answer 51

changes color

Question 52

whats color is internal meat and what happens when exposed to oxygen

Answer 52

internal meat: purple - red myoglobin when cut from carcass + exposed to O - bright red oxymyoglobin

Question 53

what happens when to meat color during storage time

Answer 53

may be further oxidized and become brownish-red metmyoglobin

Question 54

whats the number one fact influencing consumers when purchasing meat

Answer 54

color

Question 55

what does beef originate from PRIMARILY

Answer 55

cattle of various sex/age and breeds; primarily heifers (F that haven't had calves) and steers (young, castrated males)

Question 56

whats veal

Answer 56

m or f young calves; 3 weeks - 3 months

Question 57

what are yearling beef

Answer 57

older calves

Question 58

what are veal fed

Answer 58

milk-based diet + restricted in movement

Question 59

describe veal in three ways

Answer 59

- unique flavor (influenced by presence lactic acid) - fine/tender muscle fibers - free-range veal is slightly less tender