1. Meat Science 02421- Unit 16 Created by West Central High School Ag Education Hartford, South Dakota Revised by Billy Moss and Rachel Postin GA Ag Ed Curriculum Office To accompany Georgia Agriculture Education Curriculum Lesson July 2002

2. Slaughter Process w Immobilization w Animal is rendered unconscious w does not feel pain

3. Kosher Slaughter w animal is slaughtered under the regulations of the Jewish religion w animals slaughtered for Kosher markets do not have to be stunned.

4. Methods w Carbon dioxide chamber w electric shock w cartridge or mechanical bolt

5. Immobilization w allows the heart to pump in order to drain the animal’s body of blood

6. Exsanguination w process of bleeding the animal w usually done by severing the jugular vein with a sharp knife

7. Exsanguination w bleeding must be done quickly to avoid hemorrhaging w hemorrhaging can cause blood spots in the meat

8. Hemorrhage w escape of blood from ruptured blood vessels w caused by a rise in blood pressure

9. Hide and organs removed w liver w brains w pancreas w intestines w heart and kidneys

10. In the US w there are over 5000 plants that slaughter animals

11. Hogs w are dipped into scalding water and placed on a machine that scrapes the hair from the hide w some plants may skin hogs

12. Organs used for food w liver - most common w brains, pancreas, intestines, and heart w kidneys may also be used for human consumption

13. Inspectors w are present to inspect carcass and internal organs w detect any health concerns

14. Inspectors w if a problem is found with the carcass, the entire carcass may be condemned w each carcass to be sold must be inspected

15. Cooling w carcasses may be wrapped in a shroud w carcass goes through rigor mortis w carcass may be aged

16. Cooling w beef carcasses are split down the middle w sides of beef are created by sawing down the backbone

17. Carcasses w may be divided into quarters by cutting each side in two pieces. w Sides are divided at the 12th and 13th rib to form quarters

18. Carcasses w lamb carcasses are usually sent to the cooler whole as they are much smaller w hog carcasses are split into sides by cutting down the backbone.

19. Carcasses w beef and hog carcasses that have been skinned are covered in a heavy cloth soaked in salt water w called a shroud

20. Shroud w prevents the carcass from drying out

21. Carcasses w are cooled down rapidly w go through rigor mortis w muscles lock into place and carcass becomes stiff

22. Rigor Mortis w physiology is similar to muscle contractions in live animals w carcass muscles do not relax

23. Rigor Mortis w onset usually takes 6 - 12 hours for beef and lamb w 30 minutes - 3 hours for pork

24. Rigor Mortis w as enzymes and microorganisms begin to break down the muscle tissue, rigor mortis is partially relaxed

25. Cooling w Quick cooling of meat is important to minimize protein degradation w inhibit growth of microorganisms

26. Pork and Lamb w carcasses are usually cooled for 18-24 hours before cutting

27. Beef w cooled for 30 or more hours before cutting into wholesale cuts w may also be aged in the cooler for as much as a week

28. Aging w carcasses undergo a period of aging to allow enzymes and microoganims to begin the process of breaking down the tissue

29. Aging w improves tenderness and flavor w adds to the expense of processing meat

30. Aging alternatives w electric stimulation of muscles w current of 600 volts is sent through the carcass right after slaughter and before the hide is removed

31. Aging alternatives w stimulation speeds natural processes that occur after death w depletion of energy stores from the body

32. Electric stimulation w improves tenderness w improve color, texture and firmness w makes hide removal easier

33. Grading w carcasses are graded according to USDA standards w federal meat grading was established in 1925

34. Grading w administered by the AMS (Agricultural Marketing Service) of the USDA

35. Grade w certifies class, quality and condition with uniform standards

36. Quality grades w prediction of the eating quality (palatability) of the meat when properly prepared

37. Yield Grades w indicate expected yield of edible meat from a carcass and the subsequent wholesale cuts from that carcass

38. Grading w is voluntary and is paid for by the packer

39. Quality Beef Grades w prime w choice w select w standard w commercial

40. Quality Beef Grades w utility w cutter w canner

41. Grades w are determined by the age of the animal w amount of fat intermingled with the muscle

42. Age w determined by maturity of the cartilage and bones w cartilage hardens and turns to bone as the animal ages

43. Age w graders inspect the rib cage and vertebrae for the degree of bone and cartilage hardening - ossification

44. Age w as the animal ages, vertebrae in the lower end of backbone tend to fuse or grow together. w Animals older than about 42 months cannot receive the highest two grades

45. Age w younger animals are usually more tender than older animals

46. Fat w fat, known as marbling w shows up as specks of white across the rib eye w more specks of fat that are visible, the higher the grade

47. Prime w has the highest degree of fat in the muscle w fat gives meat its flavor and juiciness

48. Prime w fat is expensive to put on animals w leaner grades are less expensive

49. Feedlot operators w want their animals to grade low choice at slaughter w those raising prime animals usually cater to the restaurant trade

50. Beef w most beef bought in the grocery store is choice grade. w A few market chains are selling the leaner select grade as a low fat meat

51. Yield Grade w estimate of the percentage of boneless, closely trimmed retail cuts that come from the major lean primal cuts

52. Beef Yield grades w 1 over 52.3 % lean primal cuts w 2 50 - 52.3% w 3 47.7-50.0 w 4 45.4-47.7% w 5 less than 45.4%

53. Wholesale cuts w Primal cuts w beef w chuck, loin, rib and round

54. Wholesale cuts w pork w shoulder, loin, sides and ham

55. Wholesale cuts w lamb w shoulder, rib, loin, and leg

56. Retail cuts w primal cuts are divided into retail cuts w cuts of meat that the consumer buys at the grocery store

57. Retail cuts w sized into portions that can be easily cooked and eaten without further cutting or trimming

58. Retail Cuts w most expensive usually come from the loin area w most tender of the muscle groups w chops and steaks such as the T Bone

59. Trimmings w are made into sausage or ground meat w sausage is spiced and preserved by drying or smoking

60. Palatability w how food appeals to the palate - taste w depends upon: appearance, aroma, flavor, tenderness, and juiciness

61. Palatability w depends upon the combination of qualities and the way it is cooked

62. Appearance w beef, pork and lamb vary in the shades of red color w darker meats are associated with either a lack of freshness or meat from older animals

63. Appearance w bright red gives the appearance of being fresh and wholesome

64. Fat w that is yellow instead of creamy white is less appealing to consumers w yellow fat is found in certain breeds of animals that are unable to convert carotene

65. Fat w grain fed cattle generally have white fat and considered to taste better than grass fed beef w grass fed may have yellow fat

66. Tenderness w components of muscle that contribute to tenderness: w connective tissue, state of muscle fibers, amounts of adipose (fat ) tissue

67. Connective tissue w connects various parts of the body w is distributed throughout the body

68. Collagen w most abundant protein the animal w more activity - more collagen w as the animal ages, collagen becomes less soluble

69. Elastin w elastic like protein found throughout the ligaments, arterial walls, and organ structures w fibers are easily stretched, unaffected by cooking

70. Fresh Meats w When selecting, avoid extremes in apparent juiciness

71. Flavor changes w often occur after extended storage w chemical breakdown of nucleotides give a desirable aged flavor

72. Flavor changes w Oxidation of fats results in a rancid flavor and a sharp unpleasant aroma

73. Preservation and Storage w meat is highly perishable w spoils quickly w create conditions that are unfavorable to growth of spoilage organisms

74. Preservation and Storage w drying w smoking w salting w refrigeration

75. Preservation and Storage w freezing w canning w freeze-drying

76. Preservation and Storage w meat provides an ideal environment for microbial growth w molds w yeast w bacteria

77. Molds w multi-cellular, multicolored organisms w have fuzzy, mildew-like appearance

78. Molds w spread by spores that float in the air or transported by contact with objects

79. Yeasts w large, unicellular bud and spore forms w spread by contact or in air currents

80. Yeasts w most colonies are white to creamy in color w usually moist or slimy in appearance or to the touch

81. Microbial growth w affected by temperature w moisture w oxygen w pH physical form of the meat

82. Temperature w can influence the rate and kind of microbial growth

83. Psychrophiles w grow in cooler temperatures w 32-68 degrees F

84. Thermophiles w grow best in warmer temperatures w 45-65 degrees F

85. Mesophiles w growth optimum between psycro’s and thermo’s

86. Microbes w temperatures below 40 degrees F greatly retard the growth of spoilage microbes and prevent growth of pathogens

87. Moisture w greatly affect the growth of certain microbes w must have moisture to reproduce

88. Oxygen w availability determines the type of microbe that grows w aerobic - require free oxygen w anaerobic - grow in the absence of oxygen

89. Oxygen w facultative - grow with or without free oxygen w vacuum packaging helps to inhibit growth of aerobic organisms

90. pH w optimum pH for most microbes is near neutral (pH 7) w Molds - 2.0 - 8.0 w Yeasts 4.0 - 4.5

91. pH w bacteria 5.2 - 7.0 w meat and meat by-products range from 4.8 - 6.8 w meat conditions favor the growth of molds, yeast and acidolphilic bacteria

92. Curing and Smoking w documented as far back as 850 B.C. by the Chinese w smoking and salting (curing) only methods of preservation known

93. Curing and Smoking w imparts a particular flavor w few people in the US still rely on curing and smoking to preserve meat

94. Curing and Smoking w salt and nitrite - two main ingredients w sugar, ascorbate, erythorbate, phosphates, and delta gluconolactone

95. Curing and Smoking w salt is used in amounts to give flavor as opposed to amounts needed to preserve the meat

96. Curing and Smoking w nitrates used to impart the cured color and flavor and inhibit bacteria action w cannot amount to more than 120 ppm

97. Curing and Smoking w oldest method is dry curing w cure ingredients are rubbed onto surface of meat

98. Curing and Smoking w injection curing w pump curing solution (brine) into meat w shortens curing time

99. Curing and Smoking w combination curing w dry curing and injection curing

100. Refrigeration w fresh meat, under home refrigeration conditions should be consumed within four days of purchase

101. Freezing w blast freezing - use high velocity air and temps of –10 to -40°C w freezes meat very quickly

102. Freezing w length of time meat can be kept frozen depends on temperature, species, type of product and the wrapping material on the product

103. Freezing w wrap using vapor proof materials w keep oxygen out and moisture in w moisture loss causes freezer burn

104. Freezing w beef - 6-12 months w lamb - 6-9 months w pork - 4-6 months w cured meats - 1-2 months

105. Drying w low moisture foods contain less than 25% moisture w Beef Jerky is an example of a low moisture food

106. Drying w intermediate moisture less than 50% w dry salami