110 Metmyoglobin reducing activity and oxygen consumption properties of atypical dark-cutting beef

Abstract Deviation from characteristic bright-red color during grading leads to discounted carcass price and value. Dark-cutting carcasses are examples of color deviation due to high-pH. However, atypical dark-cutters are not discounted at grading but have a dark color compared to normal-pH beef. Limited knowledge is currently available on the biochemical properties of atypical dark cutting beef compared with normal-pH beef. Therefore, the objective of the study was to determine metmyoglobin reducing activity and oxygen consumption of atypical dark-cutting beef. Strip loins from atypical dark-cutting (ADC; selected based on HunterLab L* values and pH less than 5.8 and not discounted by grader) and USDA Low Choice (C) carcasses were selected from a commercial beef processing plant and transported to the Food and Agricultural Products Center in Stillwater, Oklahoma. pH, color, oxygen consumption, and metmyoglobin reducing activity of atypical dark cutters and normal pH loins were determined on d3 postmortem. The surface color was determined using a HunterLab Miniscan spectrophotometer. Reflectance-based methods using K/S ratios were utilized to determine oxygen consumption and metmyoglobin reducing activity. The data were analyzed using the Mixed Procedure of SAS and the experiment was replicated 10 times (n = 10). There were no differences in initial pH (C = 5.46 and ADC = 5.6 atypical dark-cutter; P = 0.05) between normal-pH and atypical dark cutters. However, atypical dark cutters had lower lightness (L* values; C = 44.2 and ADC = 38.4), redness (a* values; C = 28.6 and ADC = 25.2), and red intensity (chroma; C = 40.2 and ADC = 36.4) compared with normal-pH. Further, atypical dark cutters had greater (P < 0.05) oxygen consumption and metmyoglobin reducing activity than normal-pH. The results suggest that atypical dark cutters and normal-pH beef have different biochemical properties.

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78 Effects of extended aging, modified atmospheric packaging, and display time on metmyoglobin reducing activity and oxygen consumption of high-pH beef

Journal of Animal Science ◽

10.1093/jas/skz053.057 ◽

2019 ◽

Vol 97 (Supplement_1) ◽

pp. 26-26 ◽

Cited By ~ 1

Author(s):

Ranjith Ramanathan ◽

Andrea English ◽

Gretchen Mafi ◽

Deb VanOverbeke

Keyword(s):

Oxygen Consumption ◽

Biochemical Properties ◽

Display Time ◽

High Ph ◽

Aging Period ◽

Modified Atmospheric Packaging ◽

Extended Aging ◽

Reducing Activity ◽

Ph Range ◽

Effects Of Aging

Abstract Metmyoglobin reducing activity (MRA) and oxygen consumption (OC) are two important biochemical processes that can influence beef color. Several studies have determined the effects of aging and modified atmospheric packaging (MAP) on biochemical properties of normal-pH beef (5.5–5.7 pH range). However, limited knowledge is currently available on the effects of aging and MAP on biochemical properties of high-pH beef (> 6.2). Therefore, the objective was to determine the effects of extended aging, MAP, and display time on MRA and OC of high-pH beef. Ten USDA Choice (pH = 5.6) and ten ‘No-Roll’ dark cutting (high-pH; pH > 6.4) strip loins were obtained from a commercial packing plant within 72 hours of harvest. Loins were vacuum packaged and aged for 0, 21, 42, and 62 days at 4 °C. Following aging, from each normal- and high-pH loin sections, 2.5cm thick steaks were cut and packaged in PVC, high oxygen- (HiOx-MAP), and carbon monoxide modified atmospheric (CO-MAP) packaging. The surface color, MRA, and OC were determined on day 0 and 6 of the respective aging period. The experiment was replicated ten times (n = 10). High-pH steaks in all packaging and aging times had more stable red color than normal-pH steaks. High-pH steaks packaged in PVC and HiOx-MAP had greater (P < 0.05) MRA than normal-pH steaks. There were no differences (P > 0.05) in MRA between normal- and high-pH steaks on day 21 when steaks were packaged in CO-MAP, but high-pH had greater (P < 0.05) MRA on day 62. At all aging periods, high-pH steaks had greater (P < 0.05) OC than normal-pH steaks. However, a decrease in OC was greater (P < 0.05) for high-pH than normal-pH steaks. The results suggest that normal- and high-pH beef have different trends for the changes in MRA and OC.

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Occurrence of Antimicrobial-Resistant Escherichia coli and Salmonella enterica in the Beef Cattle Production and Processing Continuum

Applied and Environmental Microbiology ◽

10.1128/aem.03079-14 ◽

2014 ◽

Vol 81 (2) ◽

pp. 713-725 ◽

Cited By ~ 44

Author(s):

John W. Schmidt ◽

Getahun E. Agga ◽

Joseph M. Bosilevac ◽

Dayna M. Brichta-Harhay ◽

Steven D. Shackelford ◽

...

Keyword(s):

Escherichia Coli ◽

Salmonella Enterica ◽

Generation Cephalosporin ◽

Resistant Bacteria ◽

Processing Plant ◽

Cattle Production ◽

Content Type ◽

E Coli ◽

Beef Processing ◽

Tract Infections

ABSTRACTSpecific concerns have been raised that third-generation cephalosporin-resistant (3GCr)Escherichia coli, trimethoprim-sulfamethoxazole-resistant (COTr)E. coli, 3GCrSalmonella enterica, and nalidixic acid-resistant (NALr)S. entericamay be present in cattle production environments, persist through beef processing, and contaminate final products. The prevalences and concentrations of these organisms were determined in feces and hides (at feedlot and processing plant), pre-evisceration carcasses, and final carcasses from three lots of fed cattle (n= 184). The prevalences and concentrations were further determined for strip loins from 103 of the carcasses. 3GCrSalmonellawas detected on 7.6% of hides during processing and was not detected on the final carcasses or strip loins. NALrS. entericawas detected on only one hide. 3GCrE. coliand COTrE. coliwere detected on 100.0% of hides during processing. Concentrations of 3GCrE. coliand COTrE. colion hides were correlated with pre-evisceration carcass contamination. 3GCrE. coliand COTrE. coliwere each detected on only 0.5% of final carcasses and were not detected on strip loins. Five hundred and 42 isolates were screened for extraintestinal pathogenicE. coli(ExPEC) virulence-associated markers. Only two COTrE. coliisolates from hides were ExPEC, indicating that fed cattle products are not a significant source of ExPEC causing human urinary tract infections. The very low prevalences of these organisms on final carcasses and their absence on strip loins demonstrate that current sanitary dressing procedures and processing interventions are effective against antimicrobial-resistant bacteria.

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The Effect of Modified Atmospheric Packaging on Beef Color Sensory Characteristics of Different Muscle pH Categories

Meat and Muscle Biology ◽

10.22175/mmb.10709 ◽

2019 ◽

Vol 3 (2) ◽

Author(s):

A. Cassens ◽

G. Mafi ◽

D. VanOverbeke ◽

R. Ramanathan

Keyword(s):

Modified Atmosphere Packaging ◽

Processing Plant ◽

High Ph ◽

Beef Processing ◽

Modified Atmospheric Packaging ◽

Significant Difference ◽

Muscle Ph ◽

Beef Steaks ◽

Retail Display ◽

Muscle Color

ObjectivesAny deviation from the bright-red color of beef can lead to discounted price or consumer rejection. Fresh beef lean color is influenced by pH. Various packaging techniques have been developed to enhance the lean color of beef steaks. Therefore, the objective of the current study was to evaluate the effects of modified atmospheric packaging on three different beef muscle pH categories.Materials and MethodsThe three categories evaluated for this study were: Normal (pH = 5.57 ± 0.1; N-pH), Moderately high (pH = 5.70 ± 0.09; M-pH), and High (pH = 6.39 ± 0.03; H-pH). The pH was taken on the carcass, at the 12th and 13th rib interface within 72 h of harvest at a commercial beef processing plant. Strip loins were fabricated from each carcass (n = 12) and sent to Oklahoma State University for further analysis. Strip loins were then cut into 2.54 cm steaks and randomly assigned to 1 of 3 packaging treatments: polyvinyl chloride overwrap (PVC), carbon monoxide modified atmosphere packaging (CO-MAP; 0.4% CO, 69.6% N, and 30% CO2) and high-oxygen modified atmospheric packaging (HiOx-MAP; 80% O2, and 20% CO2). Visual color measurements for muscle color (MC; (1 = extremely bright cherry-red and 7 = extremely dark red), and surface discoloration (SD; 1 = no discoloration [0%] and 7 = extensive discoloration [81–100%]) were recorded on d 2, 4, and 6 of retail display by a trained panel. Data were analyzed using the Mixed Procedure of SAS.ResultsFor all pH treatments, PVC packaging possessed the darkest muscle color (P < 0.05) score compared to CO- and HiOx-MAP. When comparing N-pH, M-pH, and H-pH values, CO-MAP had approximately a 27.3%, 22.2%, and 25.3% improvement in muscle color, indicating a brighter lean color compared to PVC. Additionally, HiOx-MAP had approximately a 10.9%, 17.4%, and 16.5% improvement in muscle color score for N-pH, M-pH, and H-pH, respectively. When packaging steaks in either CO- or HiOx-MAP there was no significant difference (P > 0.05) between d 4 and 6 of retail display for muscle color. However, there was a significant (P < 0.05) darkening in muscle color for steaks packaged in PVC from d 4 to 6 of retail display. By the fourth d of retail, N-pH steaks packaged in PVC had 38.3% and 39.0% greater (P < 0.05) surface discoloration than CO- and HiOx-MAP, respectively.ConclusionThese results suggest that packaging steaks of different pH categories in CO- or HiOx-MAP can improve the surface color compared to PVC packaging.

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Effects of Aging, Modified Atmospheric Packaging, and Display Time on Metmyoglobin Reducing Activity and Oxygen Consumption of High-pH Beef

Meat and Muscle Biology ◽

10.22175/mmb2019.05.0017 ◽

2019 ◽

Vol 3 (1) ◽

pp. 276 ◽

Cited By ~ 4

Author(s):

R. Ramanathan ◽

M. C. Hunt ◽

A. R. English ◽

G. G. Mafi ◽

D. L. VanOverbeke

Keyword(s):

Oxygen Consumption ◽

Display Time ◽

High Ph ◽

Modified Atmospheric Packaging ◽

Reducing Activity ◽

Effects Of Aging

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Molybdate Reduction to Molybdenum Blue by an Antarctic Bacterium

BioMed Research International ◽

10.1155/2013/871941 ◽

2013 ◽

Vol 2013 ◽

pp. 1-10 ◽

Cited By ~ 14

Author(s):

S. A. Ahmad ◽

M. Y. Shukor ◽

N. A. Shamaan ◽

W. P. Mac Cormack ◽

M. A. Syed

Keyword(s):

Gel Filtration ◽

Potassium Cyanide ◽

Sodium Molybdate ◽

Identification System ◽

Optimal Conditions ◽

Molybdenum Blue ◽

Microbial Identification ◽

Molecular Phylogenetic ◽

Initial Ph ◽

Reducing Activity

A molybdenum-reducing bacterium from Antarctica has been isolated. The bacterium converts sodium molybdate or Mo6+to molybdenum blue (Mo-blue). Electron donors such as glucose, sucrose, fructose, and lactose supported molybdate reduction. Ammonium sulphate was the best nitrogen source for molybdate reduction. Optimal conditions for molybdate reduction were between 30 and 50 mM molybdate, between 15 and 20°C, and initial pH between 6.5 and 7.5. The Mo-blue produced had a unique absorption spectrum with a peak maximum at 865 nm and a shoulder at 710 nm. Respiratory inhibitors such as antimycin A, sodium azide, potassium cyanide, and rotenone failed to inhibit the reducing activity. The Mo-reducing enzyme was partially purified using ion exchange and gel filtration chromatography. The partially purified enzyme showed optimal pH and temperature for activity at 6.0 and 20°C, respectively. Metal ions such as cadmium, chromium, copper, silver, lead, and mercury caused more than 95% inhibition of the molybdenum-reducing activity at 0.1 mM. The isolate was tentatively identified asPseudomonassp. strain DRY1 based on partial 16s rDNA molecular phylogenetic assessment and the Biolog microbial identification system. The characteristics of this strain would make it very useful in bioremediation works in the polar and temperate countries.

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Antimicrobial Resistance in Enterococcus Spp. Isolated from a Beef Processing Plant and Retail Ground Beef

Microbiology Spectrum ◽

10.1128/spectrum.01980-21 ◽

2021 ◽

Author(s):

Devin B. Holman ◽

Cassidy L. Klima ◽

Katherine E. Gzyl ◽

Rahat Zaheer ◽

Cara Service ◽

...

Keyword(s):

Antimicrobial Resistance ◽

Ground Beef ◽

Fabrication Process ◽

Resistant Bacteria ◽

Processing Plant ◽

Agricultural Industry ◽

Beef Processing ◽

Enterococcus Spp

Antimicrobial resistance (AMR) is a serious challenge facing the agricultural industry. Understanding the flow of antimicrobial-resistant bacteria through the beef fabrication process and into ground beef is an important step in identifying intervention points for reducing AMR.

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Impacts of a New Agricultural Processing Plant on Rural Development

Journal of Agricultural and Applied Economics ◽

10.1017/s0081305200010438 ◽

1972 ◽

Vol 4 (1) ◽

pp. 73-77

Author(s):

Gerald A. Doeksen ◽

James Rathwell

Keyword(s):

Rural Development ◽

Low Income ◽

Rural Areas ◽

Agricultural Products ◽

Community Leaders ◽

Processing Plant ◽

New Firms ◽

Surplus Labor ◽

Primary Products ◽

Rural State

Community leaders of rural areas characterized by low-income and surplus labor seeking ways to promote rural development, frequently encourage new firms to process the primary products of the region. In a rural state such as Oklahoma, which is a large producer and exporter of agricultural products, interest is often focused on industries which process these goods. Impact multipliers are often used to measure income and employment impacts created from processing primary products.

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