Chapter 8 - Meat Tenderness ANSC 307

What are tenderness measurements in meat science research

~ Trained and/or consumer sensory panels

~ Warner-Bratzler shear (WBS) force

What scale do the Trained and/or consumer sensory panels test on?

9 = extremely tender; 1 = extremely tough

how does the Warner-Bratzler shear (WBS) force measure?

1/2-inch core removed from cooked steak, parallel to the muscle fibers, and mechanically sheared: lower values more tender than higher values

What meats are the relatively classified as tender?

~ Psoas major

~ Infraspinatus

~ Gluteus medius

~ Longissimus dorsi

~ triceps brachii

What meats are relatively classified as Intermediate?

~ Biceps femoris (sirloin)

~ Rectus femoris

~ Adductor

~ semitendinosus

~ Semimembranosus

~ Biceps femoris (round)

What meats are relatively classified as Tough?

~ deep pectoral

~ latissimus dorsi

~ trapezius

~ superficial pectoral

What bovine muscles are very tender? WBS < 3.2 kg

~ M. psoas major

~ M. infraspinatus

~ M. spinalis thoracis

~ M. serratus ventralis

~ M. biceps brachii

~ M. vastus medius

What bovine muscles are tender? 3.2 < WBS < 3.9 kg

~ M. longissimus thoracis et lumborum

~ M. gluteus medius

~ M. tensor fasciae latae

~ M. pectorales superficiales

~ M. teres major

~ M. rectus fermoris

~ M. rhomboideus

~ M, triceps brachii

What bovine muscles are intermediate? 3.9 < WBS < 4.6 kg

~ M. supraspinatus

~ M. gluetobiceps (M. biceps femoris)

~ M. semitendinosus

~ M. adductor

~ M. vastus lateralis

~ M. Latissimus dorsi

~ M. semimembranosus

What bovine muscles are tough? WBS > 4.6 kg

~ M. pectoralis profundus

~ M. trapezius

~ M. brachialis

~ M. extensor carpi radialis

~ M. flexor digitorum superficialis

Where are the is the tenderloin steak and top blade steaks ranked in tenderness

Tenderloin - First (5.7 lbs) and Top blade steak - Second (6.7 lbs) tender cuts

What steak is ranked as the toughest cut

Top round steak (9.0 lbs)

(T/F) Roasts are typically more tender than steak counterparts

True

What are some key differences among muscles

~ Actomyosin effect

~ Background effect

~ Bulk density/lubrication effect

What characteristics of the meat does the actomyosin effect cover?

~ Sarcomere length

~ Muscle fiber diameter

~ sarcomere/fragment

What characteristics of the meat does the background effect cover?

~ Concentration of stromal proteins

~ Size of elastin fibrils

~ Solubility of collagen

What characteristics of the meat does the bulk density/lubrication effect cover?

~ Amount of marbling

~ Distribution of marbling

(T/F) the longer the sarcomere the more tender the meat

True

What are some additional factors affecting tenderness

~ Breed type

~ Locomotive versus support muscles

~ Quality grade effects

~ Degree of doneness

(T/F) Bos indicus breeds tend to have tougher meat bos taurus breeds

true

Why does bos indicus breeds (Brahman, Sahiwal, etc.) tend to have tougher meat than bos taurus (Angus, Hereford, etc.)?

greater amounts of calpastatin, a protein that interferes with postmortem degradation of muscle.

Why does Locomotive versus support muscles affect tenderness?

less connective tissue in support muscles.

Why does Quality grade effect affect tenderness?

Prime has more marbling than Choice and Choice has more than Select.

Why does the degree of doneness effect affect tenderness?

as meat is cooked to more advanced degrees of doneness, the tougher it will get. Marbling helps to “insure” acceptable tenderness at higher levels of doneness.

(T/F) it’s easier to chew fat than protein

True

What’s the difference in diameter between a tough steak and a tender steak

Tough - 80 µm

Tender - 40 µm