Animal Products quiz 1

Skeletal muscle

mammals and avians, long multinucleated unbranched thread like cells that taper at the ends, volentary muscle, attached directly or indirectly to bones

Each muscle is covered in a

connective tissue sheath

The connective tissue sheath

extends to the interior of the muscle, has nerve fibers and blood vessels

6 myofibirl proteins

myosin, actin, titin, tropomysin, troporin, nebulin

Contractile

Myosin and actin, responsible for shortening or relaxing

Regulatory

Topomysin and troporin, allowing or permitting muscles to retract

Cytoskeletal

titin and nebulin, structural support or integrity

Myofiliments

Actin-thin filament, myson-thick filament

Muscle contraction process affects

meat quality, loss of the ability to contract and relax, affects palatability

Biochemical processes that provide energy cause ____ that affect ____

accumulation of metabolities, tenderness water holding capacity and color

Rigor Mortus

"stiffness of death" muscles continue to contract

In rigor mortus relaxation is impossible due to

no energy from no detachment of actin and myosin

What are the phases of rigor mortus

onset of rigor, rigor completion, resolution of rigor

Onset of rigor

When muscle loses extensibility

rigor completion

max contractions and max toughness, ATP exhusted and all binding sites have formed cross linkages

Resolution of Rigor

Actomyosin bonds not broken, Proteolytic degradation of myofibrillar proteins results in loss of ultrastructure integrity

what would be needed to maintain a relaxed state?

Mg2+ and ATP

Contraction

20% binding sites filled

Rigor

100% binding sites formed

Muscle contraction process affects what

meat quality

Live muscle

aeorbic and or anerobic metabolism can occur, lactic acid produced "shipped out"

Post-Mortem Muscle

metabolism will continue in short term, no circulation lactic acid can not be "shipped out"

accumulation of lactic acid

drop in pH

rapid or prolonged pH decline

pale color meat

PSE is

pale, soft, exudative

DFD is

dark firm dry

water holding capacity (WHC)

The ability of meat to retain naturally occurring or added water during application of external forces such as cutting, heating, grinding, or pressing

pH and WHC

H+ ions flood the system and PM proteins collapse onto themselves

net charge effect

pH nears isoelectric point, less capable of binding water

isoelectric point

Point at which a compound is electrically neutral

low pH

low WHC (exudatitive and soft)

high pH

high WHC (dry and coarse)

decreased WHC

increased shrink

purge

accumulated moisture exuded from meat

PSE =

low pH

DFD =

high pH

PSE and DFD are

unmarketable as high-end retail product, issues with quality and shelf life

Why is it important to reduce stress?

meat quality

AMI

American Meat Institute, authored by temple grandin

low stress handling

eaiser to handle, use flight zone and point of balance

Bruised meat

has to be cut out and cant be used for human consumption

Transportation issues

fitness for travel, cold stress, heat stress, hauled over long distances, overload vehicles, bruises or death

unfit animals for transport

weak cull animals, lame, freshly weaned, downers (BSE)

By law animals can not be transported for more than __

28 hours

What is lariage

time of rest, no less than 2 hours, hours before are most critical (hormones)

Restraint

V-boss restrainer, pigs V-belt system

Immobilization

renders animal unconcious and insesnible to pain

what if immobilization is done improperly

death, small hemmoriges, broken bones, poor bleeding

signs of effective stun

head limp and floppy, no volentary blinking, no rythmic blinking, no response to ear or nose pinch, no arched back, no vocalization

Why are animals restrained in a stunning box

provides percise placement of stunning gun

Stunning in Hogs

Electrical (epileptic like seizures and cardiac arrest) or CO2 (imporves meat quality)

Captive Bolt

Cattlie, sheep, goats, trauma to the head with a steel bolt, placement is very important

Stunning in poultry

electrical- saline solution electrified, decapitation, cervical dislocation, blunt head trauma

exsanguination

removal of blood, severing the carotid arteries and jugular veins

What is sticking?

knife penetrating sternum

When is exsanguination done?

Quickly after stunning, most hung vertically

when is Scalding and skinning done?

immediately after exsanguination

What is skinning

removal of skin or hide in sheep, goats, cattle

Scalding

hair removal in pigs and feathers in chickens, animals placed in hot water, loosens hair/feathers for removal

Removal of hide beigins with

removal of feet

Evisceration

removal of internal organs for heigene

How is Evisceration done?

Rectum is loosened by cutting around anus, esophagus is seperated from trachea befpre severed from head

After animal is dresses

Must be USDA inspected

How is Evisceration different in birds

giblets are harvested (heart, liver, gizzard)

Carcass Manipulation

split down midline (cattle, sheep, goat), pig caul fat removed

what are caracasses evaluated for

contamination and hemmorages

why are spinal cords removed in cattle

to prevent the spread of BSE

How do we define animal products?

foods or goods (raw, processed, semi processed), medicine, clothing

Animal products

meat, fiber, leather, dairy, service, recreation

What meat is eaten the most?

small rumninant

what meat is eaten in the largets amount

beef

mutton or lamb

sheep

chevon

goat

beef

cattle

milk

produced by mammals, goats, sheep, cattle, camels, yaks

Palatability

Taste, Tenderness, Juiciness and Flavor attributes

Highest species # in the world

chickens

highest specied # in the US

chickens

Concerns

ethics, green house gases, water use and quality, technology, health and quality