Fresh ham quality and composition as influenced by genetic-type, slaughter weight, diet and sex

Abstract

Six genetic lines (Berkshire, Duroc, Danbred, Newsham Hybrid, Hampshire, and DeKalb genetics) were randomly assigned to one of four diets differing in protein level (1.25, 1.1, 0.95, and 0.8% lysine) and one of three slaughter weights (114, 132, and 150 kg) within genetic line and dietary protein level. Approximately 600 animals (barrows and gilts) comprised three replicates with all treatments represented within a replicate. Hams were removed from one carcass side (24h postmortem), packaged, and shipped at 0 to 10°C to Rosenthal Meat Science & Technology Center, Texas A&M University. Hams were evaluated for shipping yield. The Gluteus medius muscle of the ham face was evaluated for pH (HI 9025C, Hanna Instruments, Limena, Italy) and reflectance, L*, a*, and b* utilizing a Minolta Chromameter (model CR-300, Minolta, Inc., Ramsey, NJ). Three trained panelists evaluated the Gluteus medius surface for color and firmness (5-point National Pork Producers Council color and firmness scale). Hams were dissected into skin, subcutaneous fat, seam fat, bone, other lean, inside ham muscle (Semimembranosus), outside ham muscle (Biceps femoris and Semitendinosus), and knuckle (Quadriceps femoris).The anterior portion of the three major ham muscles was removed to determine drip loss (%). Reflectance, L*, a*, b*, sensory color, sensory firmness, and pH were determined on the cut surface of the three major ham muscles. Ham muscles were injected with brine, packaged in CN560 cook-in bags (Cryovac Division, Sealed Air Corp., Duncan, SC), tumbled, and cooked to 71°C. Cook yields and slice yields were determined for each muscle. Genetic-type influenced ham composition and raw ham quality measures; however, genetic-type influenced only color in the cooked ham product and did not affect cooked ham sensory attributes. Diet influenced ham composition and raw ham quality attributes but did not affect the cooked ham quality or sensory attributes. Sex affected ham composition and affected some color characteristics in the ham. Slaughter weight influenced ham composition, raw and cooked ham quality, and cooked ham sensory attributes. Cut played the largest role in the determination of raw and cooked ham quality and cooked ham sensory attributes. In addition, cut was important in quality interactions with genetic-type, sex, and slaughter weight.