Grading and Factors affecting quality

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

What are quality grades?

palatability, tenderness, juiciness, flavor, overall acceptance of meat

What determine quality grades

marbiling- intra muscular fat, maturity- psycological age

How are marbling and maturity measured

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

What are quality grades for beef

PSE, RFN, DFD

what are quality grades for pork

not used by commercial pork packing industry

USDA prok quality grades

Acceptable vs unacceptable

what does industry use for pork quality grades?

color

prok grading standards

Temperment, pre-harvest stress, breed/genetics, feeding systems, calf management, growth enhancement technology, best management practices

Pre-harvest factors

chilling rate, electrical stimulation, postmoretem aging, product enhancement, cooking method, degree of doneness

Post harvest factors

moderatelt hertiable, bad temperment causes dark cuttinf carcasses, lower marbling, less tenderness

temperment

a drop in pH causes PSE

what is the relationship between quality grade and pH values

caused by antemortem stress

PSE and Stress

dark cutting beef

DFD and stress

enter retail chain, dark cutter excluded from USDA prime and premium marketing programs, PSE excluded from grade 1-4 classified as utility,

PSE and DFD are unable to

malignant hyperthermia (halothane gene)

Genetics and PSE

is a natural inhibitor of calpain

what is calpastatin

an enzyme responsible for protein breakdown

what is calpain

calpastatin

Bos indicus have a higher level of

grain fed produce more marbliing and improved tenderness

Grain vs Grass Fed

marbling, fat thickness, loin muscle area, carccass weight, and yeild grade increases. improves thenderness and flavor

the amount of time an animal is fed a high concentrate diet increases

implants can have a negative impact on tenderness

growth enhancement tech

ractopamine hydrochloride (Optaflexx)- marbling, quality grade, tenderness, lean color, maturity. Melengestral acetate (MGA)- supresses estrus in heifers no negative impach on marbling or tenderness

feed additives

affects of chemical reaction

effect on post-harvest temp

prevention of cold shortening through acceleration of glycolysis

electrical stimulation

holding carcasses or meat at refrigeration temps for extended periods, improves tenderness and flavor

aging-what does it do

marinatinf, injecting, mechanical tenderization, other value added factors

other meat enhancements