Exam 2

Dressing Percentage

The percentage of the live animal's weight that becomes the carcass after slaughter. Average is different for different species

Humane Method of Slaughter Act of 1978

Legislation requiring humane treatment of food animals during slaughter, ensuring freedom from fear, stress, and pain.

Mandates a quick and effective death for these animals

act applies to all livestock except poultry

Stunning Methods

Mechanical, chemical, and electrical stunning techniques used in slaughter to render animals unconscious before slaughter.

Specific Risk Materials (SRM)

Tissues in cattle prone to prion contamination, such as tonsils and distal ileum, requiring removal to prevent disease spread.

By-products

Secondary products from slaughter, including edible (e.g., kidneys, heart) and inedible parts (e.g., hides), processed in rendering industry.

Curing

Process involving the use of ingredients like salt, sugar, and nitrate to preserve and flavor meat through dry, injection, or combination methods.

Sausage Manufacturing

Process of creating uniform meat products through emulsion of fat particles in water using salt-soluble heat coagulable proteins.

Meat Tenderness

Quality influenced by factors like species, breed, fat content, age, and water holding capacity, measured by Warner Bratzler shear force.

Why are values so different for dressing percentage?

Weight of hide

Head and skin left (hogs)

Weight/volume of intestinal content

Muscle mass of different species

Pre slaughter management

freedom from fear/stress and freedom from pain

12-24 hour fast

makes evisceration easier

food safety- less bacteria from GI tract to meat

free access to water

helps with blood and pelt/hide removal

Mechanical stunning

concussion or penetration of the head used in cattle or sheep to render unconcious

Chemical stunning

uses CO2, used for hogs and poutry, essentailly puts them to sleep

electrical stunning

varies in voltage, amperage and time parameters, used for hogs and poultry (sometimes does not work fully)

Pros/cons of stunning methods

stun to bleeding time varies with each method

some dont always work

slower per animal (electrical)

Injuries to workers can happen

What are the steps to the slaughter process after stunning?

exsanguination → scalding/skinning → evisceration → carcass manipulation → antimicrobial intervention → electrical stimulation

exsanguination

bleeding the animal/removing the blood

scalding/skinning

removing feathers/hair/hides from specific animals (poultry, hogs, cattle, sheep)

evisceration

removal of internal organs (GI, heart, lungs, liver, etc) (for by product use)

Carcass manipulation

removal of head, foreshanks, hind shanks, bruising etc.

what is SRM

Specific risk materials

Why remove SRM’s

to prevent prion contamination that may cause TSE or BSE. Getting to the problem areas before they cause problems.

What are SRM’s

tissues in cattle that are considered high risk for prion contamination (TSE and BSE) areas are mostly the tonsils and distal ileum

after 30 mo of age other SRM’s are removed

How do you determine if a cow is older than 30 mo?

one of the 2nd set of permenant incisors have erupted

30 months and older tooth age determination

younger than 30 months

What are variety meats of a beef carcass?

kidneys, heart, liver, tongue, etc.

what is the most valuable byproduct of a cattle carcass?

the hide

what is further processing?

converts waste animal products/tissues into stable, value added materials

what are some primary byproducts

hides, fat, bones, internal organs

In what ways can you further process

rendering, drying, freezing, salting, smoking, curing

what is the curing reaction?

myoglobin + nitric oxide = nitric oxide myoglobin + heat = nitrosylhemochromagen

what does salt do for curing

gives product flavor, preserves, dehydrates meat

what does sugar do for curing

adds flavor, counteracts the salt, provides energy for bacterial conversion, lowers acidity

what does nitrate do for curing

adds flavor, prevents “warmed over” flavors, slows rancidity, slows growth of clostridium botulinum, contributes pink color

dry curing

rubbed into meats surface, good flavor/texture minimal equipment, no refrigeration of curing products, controlled bacteria, slow process, can go rancid, storage is costly, increased shrinkage, salty

injection curing

curing solution goes directly into meat (Stitch pumping, artery or machine), rapid penetration, reduces spoilage, adds alkaline phosphates, low salinity, flavor profile is diminished, texture is different

combination curing

both dry and injection methods (injection with dry cure or injection with low salt liquid and high salt pickle)

what is sausage?

any meat chopped, seasoned and formed into a uniform shape

what is emulsion?

a dispersion of fat particles in water held by the actions of salt soluble heat coagulable proteins (SSHCP)

what are the SSHCP protiens

actin, myosin, actomyosin

why are the SSHCP proteins salt soluble?

its released within muscle during emulsion by salt solution being added to mixture

why are the SSHCP’s heat coagulable

they have the ability to harden during the cooking cycle

What do the SSHCP’s do

during emulsion they coat the fat, by doing so they prevent fatting out

What is tenderness and how is it measured?

measured on a grading scale (beef and lamb) and is measured by palatability (tenderness, flavor, juiciness, collagen content etc.)

Warner Bratzler Sheer force

the pounds of force it takes to cut a ½ in core from cooked steaks and roasts

how many pounds of sheer force does it take for tough meat

12+ lbs (unacceptable)

how many pounds of sheer force does it take for marginal meat

8-12 lbs

how many pounds of sheer force does it take for tender meat

less than 8 lbs

what factors contribute to tenderness?

species, breed, fat, type of muscle (support/locomotive), age, water holding capacity,

how do you determine a carcass’s sex class

determining if the carcass has a pizzle eye (male) or a different semimembranosus

what are the 8 quality grades?

prime, choice, select, standard, commercial, utility, cutter, canner

What are the maturity groups and what are the chronological ages related to the maturity groups?

A, B, C, D, E (A being the youngest and E being the oldest)

What part of the carcass is marbling measured?

ribeye area

What degree of marbling classifies a carcass as prime, choice, or select?

Chronological age of cattle (A B C D E) Feedlot cattle (30 42 72 96) Younger cows Older cows Step-wise procedure for Quality Grading Beef Carcasses

What are the steps to quality grading?

1- determine sex class of carcass

2- determine carcass maturity

3- evaluate marbling

4- combine marbling and maturity to defermine USDA QG

How do you determine carcass maturity?

Degree of skeletal ossification in the thoracic, sacral and lumbar vertebrae

color and shape of ribs

What are the yeild grades of beef cattle

range from 1-5