Microbial ecology of beef carcasses and beef products

Lymphatic tissue, specifically lymph nodes, is commonly incorporated into ground beef products as a component of lean trimmings. Salmonella and other pathogenic bacteria have been identified in bovine lymph nodes, which may impact compliance with the Salmonella performance standards for ground beef established by the U.S. Department of Agriculture. Although Salmonella prevalence has been examined among lymph nodes between animals, no data are currently available regarding feedyard origin of the cattle and Salmonella prevalence. Bovine lymph nodes (279 superficial cervical plus 28 iliofemoral = 307) were collected from beef carcasses at a commercial beef harvest and processing plant over a 3-month period and examined for the prevalence of Salmonella. Cattle processed were from seven feedyards (A through G). Salmonella prevalence was exceptionally low (0% of samples were positive ) in cattle from feedyard A and high (88.2%) in cattle from feedyard B. Prevalence in the remaining feedyards ranged widely: 40.0% in feedyard C, 4.0% in feedyard D, 24.0% in feedyard E, 42.9% in feedyard F, and 40.0% in feedyard G. These data indicate the range of differences in Salmonella prevalence among feedyards. Such information may be useful for developing interventions to reduce or eliminate Salmonella from bovine lymph nodes, which would assist in the reduction of Salmonella in ground beef.

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Cattle as a possible source of verocytotoxin-producingEscherichia coliO157 infections in man

Epidemiology and Infection ◽

10.1017/s0950268800057162 ◽

1993 ◽

Vol 111 (3) ◽

pp. 439-448 ◽

Cited By ~ 260

Author(s):

P. A. Chapman ◽

C. A. Siddons ◽

D. J. Wright ◽

P. Norman ◽

J. Fox ◽

...

Keyword(s):

Escherichia Coli ◽

Rectal Swab ◽

Phage Type ◽

Plasmid Content ◽

E Coli ◽

Phage Types ◽

Beef Carcasses ◽

Rectal Swabs ◽

Beef Products

SummaryIn May-June 1992 cases of infection with verocytotoxin-producing (VT+)Escherichia coliO157 in South Yorkshire could have been associated with prior consumption of beef from a local abattoir. During investigation of the abattoir, bovine rectal swabs and samples of meat and surface swabs from beef carcasses were examined forE. coliO157, isolates of which were tested for toxigenicity, plasmid content and phage type.E. coliO157 was isolated from 84 (4%) of 2103 bovine rectal swabs; of these 84, 78 (93%) were VT+, the most common phage types being 2 and 8, the types implicated in the cluster of human cases. Positive cattle were from diverse sources within England.E. coliO157 was isolated from 7 (30%) of 23 carcasses of rectal swab-positive cattle and from 2 (8%) of 25 carcasses of rectal swab-negative cattle. The study has shown that cattle may be a reservoir of VT+E. coliO157, and that contamination of carcasses during slaughter and processing may be how beef and beef products become contaminated and thereby transmit the organism to man.

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Sorting beef subprimals by ribeye area size at the packer level to optimize utility and product uniformity in foodservice and retail

Translational Animal Science ◽

10.1093/tas/txaa107 ◽

2020 ◽

Vol 4 (3) ◽

Cited By ~ 1

Author(s):

Chandler C Steele ◽

Ashley N Arnold ◽

Kerri B Gehring ◽

Davey B Griffin ◽

Jeffrey W Savell

Keyword(s):

Visual Images ◽

Department Of Agriculture ◽

Sorting Method ◽

Beef Carcasses ◽

Ribeye Area ◽

Beef Products ◽

Strip Loin ◽

Instrument Grading

Abstract The objectives of the study were to evaluate if sorting beef carcasses at the packer level by loin muscle (LM) area, using instrument grading technology, would increase the consistency of three boxed beef products for the foodservice and retail sectors of the industry. U.S. Department of Agriculture (USDA) Choice beef sides (n = 100) and USDA Select sides (n = 100) were selected and stratified into five LM area categories (±2.9 cm2): 1) 77.4, 2) 83.9, 3) 90.3, 4) 96.8, and 5) 103.2 cm2. Beef lip-on ribeyes and boneless strip loins were obtained from USDA Choice sides and full, partially defatted tenderloins were obtained from USDA Select sides. Subprimals were scanned with a portioner that captured visual images and dimensional analyses of each subprimal, and data were analyzed by the software to determine multiple portioning outcomes for each subprimal. Portioning data were generated for each subprimal based on a variety of targeted portion weights (ribeye and strip loin steaks = 340.2 g; tenderloin steak = 170.1 g), as well as various portion thicknesses (ribeye and strip loin steaks = 31.8 mm; tenderloin steak = 44.5 and 50.8 mm). Subprimal utility varied across targeted portion weights and thicknesses within each LM area category. For the ribeyes and strip loins, optimal portion weight and thickness combinations were observed more frequently in LM area categories 1 and 2 than for the three larger LM area categories. Analysis of data for tenderloins revealed that LM area categories played a lesser role in identifying optimization of steak portion weight and thickness combinations. Findings demonstrate that creating categories of beef subprimals based on LM area as opposed to subprimal weight might provide a unique sorting method that would improve boxed beef product consistency and uniformity for foodservice and retail sectors.

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Biogenic Amine Formation in Fresh Vacuum-Packaged Beef During Storage at 1°C for 120 Days1

Journal of Food Protection ◽

10.4315/0362-028x-56.6.497 ◽

1993 ◽

Vol 56 (6) ◽

pp. 497-500 ◽

Cited By ~ 19

Author(s):

J. SCOTT SMITH ◽

P. BRETT KENNEY ◽

CURTIS L. KASTNER ◽

MICHAEL M. MOORE

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Monoamine Oxidase ◽

Bacterial Growth ◽

Biogenic Amine ◽

Prolonged Storage ◽

Beef Carcasses ◽

Beef Products ◽

Plate Counts ◽

Packaged Beef

Undesirable changes in vacuum-packaged beef products during prolonged storage can present a problem to some consumers. Bacterial proteolysis and decarboxylation can release pressor amines, such as tyramine and histamine, that can be toxic when ingested by individuals taking monoamine oxidase-inhibiting drugs. This study determined the effect of carcass decontamination on bacterial growth and biogenic amine production in vacuum-packaged subprimals. Beef carcasses were treated with 200 ppm chlorine or 3% lactic acid sprays, fabricated, vacuum packaged, and stored at 1°C. Samples were evaluated up to 120 d for amine concentrations, total aerobic counts, and lactic acid bacteria. Of all the amines monitored, only tyramine was consistently detected over the course of the study. Significant levels of tyramine were detected starting at day 20 of storage in all treatments and controls. By day 60, the levels had increased to about 50 μg/g and continued to increase to about 180 μg/g by 120 d of storage. Tryptamine was detected in some samples by 60 d of storage, but the levels were variable and did not follow any trend. Initial aerobic plate counts ranged from 10-200 CFU/cm2, whereas lactic acid bacteria counts were from 6-46 CFU/cm2. Bacterial numbers increased exponentially until about day 60, when they leveled off at between 106-107 CFU/cm2, with no differences between any of the treatments and/or controls. Although the vacuum-packaged beef was organoleptically acceptable up to day 60 (day 90 for some samples), it could pose some risk to individuals sensitive to biogenic amines if the product is stored at 1°C or higher for 60 d or more.

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Assessment of Salmonella Prevalence in Lymph Nodes of U.S. and Mexican Cattle Presented for Slaughter in Texas

Journal of Food Protection ◽

10.4315/0362-028x.jfp-18-288 ◽

2019 ◽

Vol 82 (2) ◽

pp. 310-315 ◽

Cited By ~ 3

Author(s):

KATHRYN J. NICKELSON ◽

T. MATTHEW TAYLOR ◽

DAVEY B. GRIFFIN ◽

JEFFREY W. SAVELL ◽

KERRI B. GEHRING ◽

...

Keyword(s):

United States ◽

Warm Season ◽

The United States ◽

South Texas ◽

Related Factors ◽

Beef Carcasses ◽

Peripheral Lymph ◽

Beef Products ◽

Positive Results

ABSTRACT Foodborne salmonellosis has been traced to undercooked ground beef and other beef products in the past, and peripheral lymph node (LN) presence in the fatty tissues of beef carcasses is one possible source of Salmonella contamination. Researchers have previously reported higher rates of Salmonella prevalence in LNs from cattle raised and harvested in Mexico compared with rates typically observed from cattle harvested in the United States. With cattle of Mexican origin comprising the majority of U.S. live cattle imports, the objectives of this study were designed to determine whether Salmonella prevalence in LNs differed (i) between cattle of Mexican and U.S. origins when exposed to the same South Texas feeding operation and (ii) between warm and cool seasons. To meet these objectives, paired (left and right sides) subiliac LNs (n = 800 LNs; n = 400 pooled samples) were collected from 100 carcasses per origin (Mexico and United States) per season (cool, December to January; warm, July to September). Overall, Salmonella prevalence in LN samples was 52.0% (208 of 400). No difference (P = 0.4836) was seen in Salmonella prevalence as a function of origin, with 54.0% (108 of 200) and 50.0% (100 of 200) of LN samples returning Salmonella-positive results from cattle of Mexican and U.S. origin, respectively. Salmonella prevalence differed (P = 0.0354) between seasons, with 46.5% (93 of 200) of cool and 57.5% (115 of 200) of warm season samples returning Salmonella-positive results. Serotyping of PCR-confirmed positive samples resulted in 14 different serovars being identified, with Cerro (21.6%), Anatum (19.7%), Muenchen (17.8%), Montevideo (14.4%), and Kentucky (12.0%) comprising the majority of serovars. These results suggest that factors other than cattle origin may be impacting Salmonella prevalence rates in bovine LNs and that additional research is needed to better understand the role of environment and management-related factors on Salmonella prevalence in bovine LNs.

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