8-Meat Tenderness

MEATS

Measurements of Meat tenderness

• Trained sensory panels:

  • 9=extremely tender….1=extremely tough

• Warner-Bratzler Shear (WBS):

  • -

Cold shortening

process whereby sarcomeres shorten dues to cold induced nervous response.

Temp with minimum cold shortening

16 degrees Celsius

Preventing cold shortening

speed up drop in pH (7-5.6) in muscle and/or slow down in the muscle temp

preventing cold shortening by increasing sarcomere length

• subQ fat thickness: .1 lamb and .25 beef

• high temp pre-rigor chilling: 16 degree celsius for 16 hrs

• electrical stimulation: 550V→ rapid decline in pH

stretching sarcomeres

• Texas A&M tenderstretch- suspension by obturator foramen

• Stouffer’s stretching devices- tamu tenderstretch plus clamps and bars

• tendercut-bones and connective tissues

calpains

**disrups myofibrils; inc activity of endogenous enzymes

stored in the cytosol near z-lines and require calcium to be activated

calpastatin

**disrups myofibrils; inc activity of endogenous enzymes

regulates calpains; the higher the calpastatin levels and activity, the less breakdown of myofibrils

Cooler aging

**disrups myofibrils; inc activity of endogenous enzymes

storage fro 1-6 weeks at 0-3 degrees celsius

species that doesnt cold-shorten because of “white” muscle fibers

pork/swine

0.10 inch in lamb; 0.25 inch in beef. Slows down temperature drop in muscle.

subcutaneous fat thickness

16°C for 16 hours immediately after slaughter.

pre-rigor chilling

suspension by the obturator foramen. Hindleg acts as a cantilever.

Texas A&M Tenderstretch

TAMU Tenderstretch plus clamps and stretching rods

Stouffer's Stretching Devices

bones and connective tissues are cut around muscles to allow stretching.

tendercut

apid pH decline ruptures lysosome and releases cathepsin with violent contractions cause myofibril tearing

electrical stimulation

re-rigor infusion or post-rigor injection of a solution of calcium chloride into muscle. Causes increased activity of calpain

Calcium chloride infusion/injection

machines with multiple blades and/or needles that penetrate meat as it passes through on a conveyor.

needle tenderizer

scoring, dicing, cubing, grinding or chopping.

mechanical severance

placing meat in a sealed water-filled chamber and setting off an explosion. Destroys most of the Z-lines to greatly improve tenderness

hydrodyne

water solution with 2% NaCl plus acetic acid.

Marination with salt and vinegar

use of fungal enzyme: Aspergillus oryzae.

Rhozyme

Mechanical severance and Blade or needle tenderization

Severance of stromal proteins

cook for a long time with steam generation: braise, stew, simmer which converts collagen to gelatin

moist heat cooker