ACCURACY OF GRID PRICING: AN EVALUATION USING WHOLESALE VALUES OF FED CATTLE

Grid pricing is one of the beef industry's answers to improving value coordination in fed cattle transactions. This paper constructs individual carcass-level grid and wholesale beef values. These values are used to evaluate the level of value communication that occurs between wholesale and grid values of beef. Furthermore, the values are used to estimate grid premiums/discounts that improve value communication. Results indicate that value coordination could be improved by modifying grid premiums/discounts.Marketing,

Valuing Fed Cattle Using Slice Shear Force Measurements

Marketing fed cattle using grid pricing has become a popluar way to sell cattle. One of the most important beef characteristics, according to consumers, is beef tenderness. USDA quality grades are poor predictors of meat tenderness. However, mechanical shear force does objectively measure tenderness. This study illustrates how problematic USDA quality grades are at assessing accurate beef tenderness and proposes and evaluates a tenderness-based valuation system based on slice shear force technology. We show that cattle of all quality grades are substantially over- or under-valued when using a grid realtive to a tenderness-based valuation system.Marketing,

Efficacy of Hypobromous Acid as a Hide-On Carcass Antimicrobial Intervention

Escherichia coli O157:H7 and Salmonella on cattle hides at slaughter are the main source of beef carcass contamination by these foodborne pathogens during processing. Hypobromous acid (HOBr) has been approved for various applications in meat processing, but the efficacy of HOBr as a hide antimicrobial has not been determined. In this study, the antimicrobial properties of HOBr were determined by spraying cattle hides at either of two concentrations, 220 or 500 ppm. Treatment of hides with 220 ppm of HOBr reduced the prevalence of E. coli O157:H7 on hides from 25.3 to 10.1% (P , 0.05) and reduced the prevalence of Salmonella from 28.3 to 7.1% (P \u3c 0.05). Treatment of hides with 500 ppm of HOBr reduced (P , 0.05) the prevalence of E. coli O157:H7 on hides from 21.2 to 10.1% and the prevalence of Salmonella from 33.3 to 8.1%. The application of 220 ppm of HOBr reduced (P \u3c 0.05) aerobic plate counts, total coliform counts, and E. coli counts on hides by 2.2 log CFU/100 cm2. The use of 500 ppm of HOBr resulted in reductions (P \u3c 0.05) of aerobic plate counts, total coliform counts, and E. coli counts by 3.3, 3.7, and 3.8 log CFU/100 cm2, respectively, demonstrating that the use of higher concentrations of HOBr on hides resulted in additional antimicrobial activity. These results indicate that the adoption of a HOBr hide wash will reduce hide concentrations of spoilage bacteria and pathogen prevalence, resulting in a lower risk of carcass contamination

Efficacy of Hypobromous Acid as a Hide-On Carcass Antimicrobial Intervention

Escherichia coli O157:H7 and Salmonella on cattle hides at slaughter are the main source of beef carcass contamination by these foodborne pathogens during processing. Hypobromous acid (HOBr) has been approved for various applications in meat processing, but the efficacy of HOBr as a hide antimicrobial has not been determined. In this study, the antimicrobial properties of HOBr were determined by spraying cattle hides at either of two concentrations, 220 or 500 ppm. Treatment of hides with 220 ppm of HOBr reduced the prevalence of E. coli O157:H7 on hides from 25.3 to 10.1% (P , 0.05) and reduced the prevalence of Salmonella from 28.3 to 7.1% (P \u3c 0.05). Treatment of hides with 500 ppm of HOBr reduced (P , 0.05) the prevalence of E. coli O157:H7 on hides from 21.2 to 10.1% and the prevalence of Salmonella from 33.3 to 8.1%. The application of 220 ppm of HOBr reduced (P \u3c 0.05) aerobic plate counts, total coliform counts, and E. coli counts on hides by 2.2 log CFU/100 cm2. The use of 500 ppm of HOBr resulted in reductions (P \u3c 0.05) of aerobic plate counts, total coliform counts, and E. coli counts by 3.3, 3.7, and 3.8 log CFU/100 cm2, respectively, demonstrating that the use of higher concentrations of HOBr on hides resulted in additional antimicrobial activity. These results indicate that the adoption of a HOBr hide wash will reduce hide concentrations of spoilage bacteria and pathogen prevalence, resulting in a lower risk of carcass contamination

Efficacy of Antimicrobial Interventions Used in Meat Processing Plants against Antimicrobial Tolerant Non–Antibiotic-Resistant and Antibiotic-Resistant Salmonella on Fresh Beef

Salmonella is a common cause of foodborne illness in the United States, and several strains of Salmonella have been identified as resistant to antibiotics. It is not known whether strains that are antibiotic resistant (ABR) and that have some tolerance to antimicrobial compounds are also able to resist the inactivation effects of antimicrobial interventions used in fresh meat processing. Sixty-eight Salmonella isolates (non-ABR and ABR strains) were treated with half concentrations of lactic acid (LA), peracetic acid (PAA), and cetylpyridinium chloride (CPC), which are used in beef processing plants to screen for tolerant strains. Six strains each from non-ABR and ABR Salmonella that were most tolerant of LA (2%), PAA (200 ppm), and CPC (0.4%) were selected. Selected strains were inoculated on surfaces of fresh beef and subjected to spray wash treatment with 4% LA, 400 ppm PAA, or 0.8% CPC for the challenge study. Tissue samples were collected before and after each antimicrobial treatment for enumeration of survivors. Spray treatment with LA, PAA, or CPC significantly reduced non-ABR Salmonella and ABR Salmonella on surfaces of fresh beef by 1.95, 1.22, and 1.33 log CFU/cm2, and 2.14, 1.45, and 1.43 log CFU/cm2, respectively. The order of effectiveness was LA . PAA = CPC. The findings also indicated that LA, PAA, and CPC were equally (P ≤ 0.05) effective against non-ABR and ABR Salmonella on surfaces of fresh beef. These data contribute to the body of work that indicates that foodborne pathogens that have acquired both antibiotic resistance and antimicrobial tolerance are still equally susceptible to meat processing antimicrobial intervention treatments

A Farm-to-Fork Quantitative Microbial Exposure Assessment of β-Lactam-Resistant \u3ci\u3eEscherichia coli\u3c/i\u3e among U.S. Beef Consumers

Integrated quantitative descriptions of the transmission of β-lactam-resistant Escherichia coli (BR-EC) from commercial beef products to consumers are not available. Here, a quantitative microbial exposure assessment model was established to simulate the fate of BR-EC in a farm-to-fork continuum and provide an estimate of BR-EC exposure among beef consumers in the U.S. The model compared the per-serving exposures from the consumption of intact beef cuts, non-intact beef cuts, and ground beef. Additionally, scenario analysis was performed to evaluate the relative contribution of antibiotic use during beef cattle production to the level of human exposure to BR-EC. The model predicted mean numbers of BR-EC of 1.7 x 10-4, 8.7 x 10-4, and 6.9 x 10-1 CFU/serving for intact beef cuts, non-intact beef cuts, and ground beef, respectively, at the time of consumption. Sensitivity analyses using the baseline model suggested that factors related to sectors along the supply chain, i.e., feedlots, processing plants, retailers, and consumers, were all important for controlling human exposure to BR-EC. Interventions at the processing and post-processing stages are expected to be most effective. Simulation results showed that a decrease in antibiotic use among beef cattle might be associated with a reduction in exposure to BR-EC from beef consumption. However, the absolute reduction was moderate, indicating that the effectiveness of restricting antibiotic use as a standalone strategy for mitigating human exposure to BR-EC through beef consumption is still uncertain. Good cooking and hygiene practices at home and advanced safety management practices in the beef processing and post-processing continuum are more powerful approaches for reducing human exposure to antibiotic-resistant bacteria in beef products

Selection Enhanced Estimates of Marker Effects on Means and Variances of Beef Tenderness

Historic surveys of retail beef have identified beef tenderness as a critical issue to consumer acceptability of beef and suggested continued investigation of pre-harvest and postharvest interventions to improve beef tenderness (Morgan et al., 1991). Koohmaraie (1996) identified the protease μ-calpain (CAPN1) and its inhibitor calpastatin (CAST) as major factors affecting post-mortem tenderization in meat. Genetic markers in CAPN1 (Page et al., 2002; White et al., 2005) and CAST (Casas et al., 2006; Morris et al., 2006) are commercially available to beef producers. However, early studies evaluating these markers had low frequency of rare homozygote animals and occasionally ignored those animals from analysis (White et al., 2005; Morris et al., 2006) – removing the opportunity to evaluate mode of inheritance (additive or dominance) for a genetic marker. Therefore, selection was used in 2 populations (Angus and U.S. Meat Animal Research Center III – ¼ Angus, ¼ Hereford, ¼ Red Poll, and ¼ Pinzgauer composite) to equalize the allele frequency of CAPN1 haplotypes and CAST genotypes to enhance estimates for slice shear force (SSF) of: 1) effect size, 2) mode of inheritance, and 3) interaction between CAPN1 and CAST (Tait et al., 2014a; Tait et al., 2014b). Furthermore, these studies evaluated the potential for genotype specific residual variances and found these models to fit significantly better than single residual variance models for CAST genotypes