Effects of Zilpaterol Hydrochloride Supplementation on Growth Performance, Carcass Characteristics and Meat Quality for Steers Differing in Breed Type.

To determine the effects of zilpaterol hydrochloride (ZH) on growth performance, carcass characteristics and meat quality for steers differing in breed type, steers with British (B; n = 76) or British × Continental (BC; n = 57) backgrounds were allocated to a randomized incomplete block design with a 2 × 2 treatment structure. Pens within each block × breed type were randomly assigned to either ZH (8.3 mg/kg of DM; fed for 20 d before slaughter, followed by a 3-day withdrawal) or control (CON; 0 mg/kg ZH). Steers were subjected to ultrasound immediately before ZH inclusion and following withdrawal to determine the influence of ZH on changes in longissimus muscle area (LMA), fat thickness and percent intramuscular fat (IMF). Carcass data were collected, and the longissimus lumborum was collected for analysis of tenderness, moisture percentage, crude fat content, collagen content, postmortem proteolysis and sensory attributes. The ZH × breed type interaction did not influence (p > 0.05) the feedlot performance, carcass or meat quality attribute traits evaluated, with the exception of moisture percentage. Responses among breed types were as expected for B vs. BC cattle types. Supplementation with ZH improved (p < 0.05) LMA and yield grade but increased Warner-Bratzler shear force.

Instrumental Color Measurements Have Relationships to Fat Smearing in Fresh Sausage.

Fat smearing, or poor fat particle definition, impacts the visual quality of sausage. However, objective methods of assessing fat smearing have not been identified. Therefore, the objective of this experiment was to determine the relationship between fat smearing and instrumental color analysis for fresh sausages to create a standard method for using instrumental color in fat smearing analysis. Meat blocks of pork (PK), beef (BF), and a mixture of pork and beef (P/B) were formed and processed at three different temperatures to create varying degrees of fat smearing. The average fat smearing score of each sausage was used to determine if a relationship existed with instrumental color measurements (CIE L*, a*, b*, and reflectance percentage at 580 nm and 630 nm) and color calculations. A correlation was observed for L* (R = -0.704) and the reflectance at 580 nm (R = -0.775) to PK fat smearing (p < 0.05). In P/B sausage, both reflectances at ratios between 630 nm and 580 nm were correlated to P/B fat smearing. No measurement or calculation was correlated with BF fat smearing (p > 0.05). Therefore, it is possible to use instrumental color analysis for the evaluation of fat smearing in pork and pork/beef blended sausage products, but not in beef sausage products.

Processed Meat Characteristics between Commercial Duroc-Sired and Heritage Breed Large Black Pigs.

This study examined the meat processing characteristics between Duroc-sired (DS) and heritage breed Large Black (LB) pigs fed high forage (FIB) or commercial diets (CON). Fifty pigs (DS, n = 25; LB, n = 25) were used in a 2 × 2 factorial design with breed and diet as fixed effects. Processing traits were measured for fresh bellies, bacon slices, and sausage patties. Results showed that DS bellies were longer (p < 0.001) but thinner (p = 0.026). CON bellies were longer (p = 0.005) and thicker (p < 0.001). LB bellies had decreased lean area (p < 0.001) and processing yield (p = 0.001). DS patties were lighter (L*, p < 0.001) and less red (a*, p < 0.001). LB had increased belly firmness (p = 0.053). The CON diet resulted in better particle definition (p = 0.010) in patties as well as a larger slice area (p = 0.048) in bacon slices. A breed × diet interaction was observed for lipid oxidation (p = 0.001). The findings provided novel insight into the comparison between these breeds and diets. While LB pork may have niche market value, the integration of this breed into commercial bacon processing has limitations in composition that need to be further evaluated to improve the product desirability.

Heat Stress and an Immune Challenge Influence Turkey Meat Quality, but Conspecific-Directed Pecking Behavior Does Not.

Heat stress (HS), immune challenges (IC) and pecking behavior are some of the many stressors poultry can experience in commercial settings that may affect bird welfare and meat quality after harvest. The first objective was to determine if HS or IC turkeys displayed greater negative effects on meat quality, and the second objective was to determine if the frequency of non-aggressive pecking behaviors among the birds was related to meat quality. Ninety-two, commercial male, beak-trimmed turkeys were used with a total of 15 rooms and 4-7 birds per room. Each treatment was applied for 1 week prior to harvest: the Control (CON) group had no stressors added, the HS group ambient temperature was approximately 29 °C for 120 min, and the IC group involved inoculating birds with a live vaccine for hemorrhagic enteritis virus. Birds were recorded and scored to quantify pecking behavior. Once harvested, carcasses were evaluated for feather retention force, pH, color, proximate analysis, fatty acid composition, shear force, and drip loss. Stress treatment resulted in HS breasts having the lowest protein content, and IC breasts having the lowest CIE L* values and the greatest shear force values. Pecking behavior had no impact on any meat quality attributes.

Impact of Antimicrobial Carcass Washes and Processing Techniques on Quality Attributes of Beef Frankfurters.

The objective of this study was to determine the impact of antimicrobial carcass washes on beef trim in the production of frankfurters. Twenty-four beef carcasses had different antimicrobial wash treatments (TRTs) randomly applied during the harvest procedure: 82 °C water (CON), peroxyacetic acid (PAA), or lactic acid (LA). Frankfurters were produced using carcass trim at two different batter temperature processes (PROC): 4 °C (LTP) and 21 °C (HTP). Frankfurters were analyzed for processing yield (PY), emulsion stability (ES), instrumental external and internal color (CIE L*, a*, b*), purge loss, texture, and sensory analysis. TRT had very little impact on frankfurter characteristics with a difference found in ES water and instrumental hardness (p < 0.05). PROC impacted ES water, ES fat, PY, instrumental springiness, external and internal color, sensory hardness, cohesion, and juiciness (p < 0.05). However, no TRT × PROC interactions were found to be significant (p > 0.05). These data indicate that antimicrobial carcass washes had little impact on frankfurter quality, while the processing technique impacted several frankfurter quality characteristics. This indicates that processors can impact frankfurter composition via processing techniques without concern of antimicrobial washes influencing frankfurter quality.