ANSC 107 1nd Edition Lecture 10 Outline of previous lecture I II III IV Muscle color Marketing a Changes Vertical integration Natural vs organic Outline of current lecture I II Evaluation of slaughter animals a Yield grade b Quality grade c Dressing Factors influencing value of slaughter animals a Dressing percent b Fatness c Marbling d Muscling e Carcass weigh and age These notes represent a detailed interpretation of the professor s lecture GradeBuddy is best used as a supplement to your own notes not as a substitute Evaluation of Slaughter Animals Learning objectives To understand the purpose of evaluating slaughter animals o To determine value To understand the differences between grading and inspecting o Grading giving it a value optional o inspecting mandatory To be able to calculate yield grades of beef pork and lamb o example 17 adjusted fat thickness What is the yield grade 1 7 4 2 1 Most livestock are sold on a live weight basis based on carcass merit o beef cattle and sheep most of the time o swine all the time grade and yield o Buyers must estimate dressing percent carcass quality grade and yield for bid Dressing percent Yield Efficiency How much fat Quality grade Determines value Industry moving to grid system o Get paid based on what you are We sell livestock on the average we would like to sell them on value based marketing Cattle Trends 1940 s o Yield 4 5 1980 s too large lost efficiency present o in the middle body muscle growth all marketing Carcass Value depends on Age Weight Sex Fatness Muscling Factors influencing value of slaughter animals Factors affecting carcass value Dressing percent Fatness Marbling Muscling Carcass weigh and age Dressing percent Carcass wt live wt x100 Factors influence DP o Fill contents of viscera gastric intestinal tract o Fat increases DP also increases o Muscle increases DP also increases o Mud Animals are often excessively fattened when DP pays a major role in pricing equation Fatness finish Excessive fat will have a negative effect on curability Enough fat is needed to provide for adequate quality and to prevent carcass shrinkage As an animal gets fatter their shape changes and they become o Squarer they lose the muscle definition o Deeper bodied lay fat in low 1 3 o Smoother in their muscle lose definition o Wider Of the major fat deposits marbling is the last deposited Animals will deposit fat from front to rear with marbling beginning in the lasts Marbling Marbling is the fat dispersed within muscle groups contributes to palatability Primary factor influencing quality grade Difficult to estimate in live cattle o Breed o Frame size small medium large o Time on feed No fat is good right Quality grade odds of poor steak o Prime 1 in 26 o Upper 2 3 of choice 1 in 19 o Lower 1 3 of choice 1 in 7 o Select 1 in 5 o Standard 1 in 2 Muscling Goal in red meat production in high quality lean muscle Muscle has shape is expressive Muscle can be measured with ultrasound A lot of variation in muscularity o Most common indicator of muscling is Longissimus Dorsi LD muscle Weight and Age Meat from older animals is less tender with more flavor Age Weight extremely variable Problems o Light animals discounted cost same as large o Over weight animals discounted due to too large cuts Wont fit in box Appropriate weight ranges o Beef 1000 1300 o Sheep 100 150 o Swine 200 270 o Weights have fixed costs in terms of processing Buyers protective system Young cherry red Mature darker Break joint determines age of sheep carcass o Lambs Sex and Sex condition Intact males are leaner than females and male castrates o Testosterone At the same weight gilts are leaner than barrows At the same weight steers are leaner than heifers wethers are leaner than ewe lambs Heifers generally discounted 1 50 3 00 due to possibility of pregnancy DP and increased seam fat At the same weight bulls are leaner than steers but have lower quality grade By products Major portion of value of slaughter animals o Hogs 7 cattle 13 and sheep 9 12 Hides are highest value o Brands cause discounts o Scratches cause discounts Large of liver loss from feed yard cattle due to abscesses Injuries and Health Bruises represent a loss of value that can be avoided through proper handling and use of proper equipment Animals found to be sick and in ante mortem inspection are not allowed into food chain Carcasses are inspected post mortem and certifies to be free of disease filth etc Inspection vs grading Inspection required o First line of defense against adulterated meat and poultry products o Responsible inspection of animals before and after slaughter Grading optional o Composite evaluation of carcass maturity firmness texture color of lean and the amount and distribution of marbling within the lean Summary Weight is determined by as scale but in some situations its is estimated Dressing Fat thickness a muscling parameter yield grade and quality grade 30 accurate is estimated A value is estimated based upon the above o Yield grade 5 smooth and round Better quality grade o Yield grade 1 has shape More efficient Calculation of yield Grades Lamb o Leg loin rack and shoulder o Yield grade 0 4 10 x adj fat thickness Adj fat 22 YG 0 4 2 2 2 6 YG 2 Pork o Ham loin Boston butt picnic shoulder o Last rib backfat LRB 12th and 13th rib o Muscle thickness ms Thin 1 avg 2 thick 3 YG 4 x LRB ms Aging beef Beef can be aged for 11 days Gives a stronger more intense flavor Must be in a clean high humidity environment o 30 35 degrees F can absorb off flavors