meat science

safety

risk of hazard when eating

quality

sensory acceptance

wholesomeness

impact on health

hyperplasia

increased number of muscle cells

hyperplasia occurs …

prior to birth

hyperplasia is __ management

materal

problem with hyperplasia

often causes dystocia

example of hyperplasia

belgian blue cow

is there regulation around hyperplasia?

no

hypertropy

increased muscle cell size (diameter/length)

hypertrophy occurs …

after birth (some in-utero)

hypertrophy is __ management

exercise/nutrition

example of hypertrophy (gene)

callipyge gene in sheep

think, dairy cattle = __ & beef cattle __

marathon runners; sprinters

we say muscle when we refer to a …

live animal

we say meat when we refer to a …

carcass

meat

any animal tissues that are suitable for food (skeletal muscle, organ meat)

categories of meat

‘red’ meats aka 4 footed livestock, poultry, fish/seafood, game

esophagus/GI tract is __ muscle

smooth

heart is __ muscle

cardiac

muscle is __ muscle

skeletal

composition of skeletal muscle

75% water, 18.5% protein (varies by species/type), 3% lipids (varies by muscle), 1% carb, 1% inorganic materials (minerals)

muscle → meat processing, immobilization

stunning the animal making it brain dead

muscle → meat processing, exsanguination

bleeding the animal out from the jugular vein & carotid artery; the step where animal truly becomes a carcass; cause of death: blood loss & lack of oxygen

muscle → meat processing, metabolic shift

cells switch to functioning aerobic to anaerobic which leads to a build up of lactic acid

build up of lactic acid leads to

a pH decrease

if the pH were to drop too fast, you get

pale, soft meat

if the pH were to drop too slowly, you get

dark, firm meat

eventually, rigor mortis occurs meaning

no more muscle “sliding”, body is stiff

PSE stands for

pale, soft, and exudative

quality problems for pork

PSE

quality problems for beef

dark cutters

PSE is caused by __ stress due to …

acute; poor animal handling

PSE results in

excessive protein denaturation, poor water-holding capacity, very dry and pale meat

dark cutters result in

limited protein denaturation, exceptional water-holding capacity, dark (ugly) meat, juicy but lacks flavor

quantity (loss) problems are caused by __ and __
they increase when new animal groups are combined due to __ __
this results in __ loss but is not a __ issue

bruising; broken bones
re-establishing dominance
money; food safety

meat is most tender where is the

least locomotion

any meat from __ will be the least tender due to __

limbs; locomotion/strain

livestock cover/deposit fat from __ → __

front → back (head → tail)

principles of meat cutting, separate __ from __

tender cuts from less tender cuts; lean from fatter cuts; thick from thin cuts; valuable from less valuable

small ruminant carcasses are kept __

whole

pork & beef carcasses are kept __

in halves

25% of value is coming from __ & __ parts of the beef carcass

rib; loin

5 main sausage types

1. fresh

2. uncooked, smoked

3. fully cooked (RTE)

4. luncheon loaves

5. dry & semi-dry

what characterizes fresh sausage

raw product; must be cooked before consumption

why might fresh sausage be declining in popularity

requires cooking (less convenient), shorter shelf life, higher food safety risk compared to RTE products

uncooked, smoked sausage is more popular in

Europe

what are luncheon loaves

similar to RTE products but made in larger diameter formats (e.g. boneless ham)e

examples of dry & semi-dry sausages

snack sticks, salami, summer sausage

why do dry and semi-dry sausages have long shelf life?

reduced moisture (low water activity) and curing

ingredients added in meat processing

water, salt, phosphate, sweeteners, flavorings, nitrite

why are water & salt added during meat processing

the salt denatures the proteins, allowing them to bind to more water improving the water-holding capacity making the meat more juicy

function of phosphate in meat processing

increases pH, improve water-holding capacity, enhance tenderness and yield

why are sweeteners (e.g., dextrose) added to processed meats?

counteract saltiness, balance flavor, sometimes support fermentation (in dry sausages)

in which products is nitrite used?

cured products (e.g., bacon, ham).

what minerals are in meat

iron & zinc

what B-vitamins are in meat

B1-3, B5, B6, B12

recommended consumption (varies by age group)

5-7 oz. of meat daily (eggs as well)

list the 3 food safety hazards

physical, chemical, biological

examples of physical hazards

glass, plastics, wood, rubber, metal

examples of chemical hazards

allergens, cleaning solutions, mechanical lubricants

examples of allergens

soy, peanuts, wheat, seafood(fish)/shellfish, dairy, tree nuts, eggs, sesame

examples of biological hazards

vacteria, fungus, parasites

danger zone

40-140°F for more than 4 hours (bacteria reproduce)

what are the two main strategies for controlling foodborne illness?

keep microbes out & kill or control the microbes that get in

how do you keep microbes out of food?

good hygiene, proper sanitation, avoid cross-contamination

what is cross-contamination?

the transfer of harmful microorganisms from one surface, food, or person to another (e.g., raw meat to ready-to-eat food).

refrigeration & freezing __ microbial growth but __ kill everything

slow; do not

manage microbial growth through

refrigeration, cooking, proper thawing

safe thawing methods

in the fridge, in cold water, in the microwave

thawing at room temp is

unsafe due to microbial growth

primal cuts of beef

chuck (shoulder), rib (upper mid-back), loin (short loin + sirloin) - lower back, round (hindquarters/rump & thigh), flank (lower belly/abdomen), short plate (lower chest/belly — below the rib), brisket (breast/chest), shank (upper leg — fore & hind)

most important/valuable cuts of beef

rib & loin (+sirloin)

retail cuts of pork

loin → pork chops & tenderloin

belly → bacon

primal cuts of pork

butt (upper front shoulder), loin (back, from shoulder to hip), ham (hindquarters/hind leg), belly (belly), sparerib (lower ribs/side, connected to the belly), picnic (lower front shoulder), jowl (cheek/jaw)

primal cuts of small ruminants (sheep & goat)

shoulder (front leg & shoulder), rack (upper mid-back ribs), loin (lower back, behind the rack), leg (hindquarters/hind leg), breast & foreshank (front lower)