Effects of Acetic Acid, Lactic Acid and Trisodium Phosphate on the Microflora of Refrigerated Beef Carcass Surface Tissue Inoculated with Escherichia coli O157:H7, Listeria innocua, and Clostridium sporogenes†

1997 ◽  
Vol 60 (6) ◽  
pp. 619-624 ◽  
Author(s):  
WARREN J. DORSA ◽  
CATHERINE N. CUTTER ◽  
GREGORY R. SIRAGUSA
Keyword(s):  
Escherichia Coli ◽  
Lactic Acid ◽  
Antimicrobial Treatment ◽  
Listeria Innocua ◽  
Trisodium Phosphate ◽  
Aerobic Bacteria ◽  
Escherichia Coli O157 ◽  
Clostridium Sporogenes ◽  
Antibiotic Resistant ◽  
Beef Carcass

The microbial profiles of inoculated beef carcass tissue (BCT) were monitored during prolonged refrigerated vacuum-packaged storage following antimicrobial treatment. An industrial spray wash cabinet was used to deliver water (W), 1.5 and 3.0% lactic (LA) or acetic (AA) acid, or 12% trisodium phosphate (TSP) washes. Fresh unaltered bovine feces spiked with antibiotic-resistant strains of Escherichia coli O157:H7, Listeria innocua, and Clostridium sporogenes were used to inoculate BCT prior to all treatments. The effect of treatments on bacterial populations was tracked by monitoring levels of specific-antibiotic-resistant(marked) bacteria along with mesophilic aerobic bacteria (APC), lactic acid bacteria (LAB), and pseudomonads for up to 21 days of storage at 5°C. Initial APC levels of approximately 5.6 log CFU/cm2 were reduced by 1.3to 2.0 log CFU/cm2 by LA, AA, and TSP treatments. Marked bacteria were reduced to <1.3 log CFU/cm2, remaining that way throughout the 21-day storage. TSP treatments were not different in effectiveness from acids for controlling growth of E. coli O157:H7 and C. sporogenes, but were less effective for APC, L. innocua, or LAB. The aerobic bacteria, L. innocua, and LAB had counts ≥7 log CFU/cm2 by 7 days in all but one case and by 14 days all had counts >7 log CFU/cm2 on the untreated controls and water-washed samples. Treatments generally added a degree of safety regarding the foodborne pathogens and pathogen models used for the present study when beef tissue was stored up to 21 days and in no case did the treatments appear to offer any competitive advantage to select microorganisms on BCT.

Effects of Steam-Vacuuming and Hot Water Spray Wash on the Microflora of Refrigerated Beef Carcass Surface Tissue Inoculated with Escherichia coli O157:H7, Listeria innocua, and Clostridium sporogenes†

1997 ◽  
Vol 60 (2) ◽  
pp. 114-119 ◽  
Author(s):  
WARREN J. DORSA ◽  
CATHERINE N. CUTTER ◽  
GREGORY R. SIRAGUSA
Keyword(s):  
Escherichia Coli ◽  
Hot Water ◽  
Listeria Innocua ◽  
Escherichia Coli O157 ◽  
Clostridium Sporogenes ◽  
Bacterial Populations ◽  
Antibiotic Resistant ◽  
E Coli ◽  
Resistant Strains ◽  
Beef Carcass

The fates of several bacterial populations on beef carcass surfaces were examined immediately following hot water washes (W) delivered through a beef carcass wash cabinet or application of steam-vacuum (SV). Additionally, the long-range effectiveness of W and SV on several bacterial populations was also determined during storage up to 21 days at 5°C under vacuum-packaged conditions. Fresh, unaltered bovine feces spiked with antibiotic-resistant strains of Escherichia coli O157:H7, Listeria innocua, and Clostridium sporogenes were used to inoculate beef carcass tissue prior to W or SV treatment. All treatments were equally effective as is indicated by bacterial populations immediately following any of the treatments (P > 0.05); however, the combination of SV followed by W consistently produced arithmetically greater bacterial reductions. In general, all treatments produced initial reductions of up to 2.7 log CFU/cm2 for APC, lactic acid bacteria, and L. innocua, but by 14 days bacterial numbers had increased to levels of at least 7 log CFU/cm2. E. coli O157:H7 was initially reduced by as much as 3.4 log CFU/cm2 and did not grow to original inoculation levels for the duration of the experiment. Vegetative counts of C. sporogenes were initially reduced by as much as 3.4 log CFU/cm2, and numbers continued to decline for the duration of the study. These results indicate that the use of W and SV effectively reduces bacterial populations from beef carcass tissue immediately after treatment. Additionally, storage of treated tissue up to 21 days at 5°C did not appear to offer any competitive advantage to potentially pathogenic microorganisms.

Control of Escherichia coli O157:H7 with Sodium Metasilicate

2004 ◽  
Vol 67 (7) ◽  
pp. 1501-1506 ◽  
Author(s):  
GEORGE H. WEBER ◽  
JUDY K. O'BRIEN ◽  
FREDRIC G. BENDER
Keyword(s):  
Escherichia Coli ◽  
Lactic Acid ◽  
Room Temperature ◽  
Sodium Metasilicate ◽  
Antimicrobial Activities ◽  
Intervention Strategies ◽  
Trisodium Phosphate ◽  
Escherichia Coli O157 ◽  
E Coli

Three intervention strategies—trisodium phosphate, lactic acid, and sodium metasilicate—were examined for their in vitro antimicrobial activities in water at room temperature against a three-strain cocktail of Escherichia coli O157:H7 and a three-strain cocktail of “generic” E. coli. Both initial inhibition and recovery of injured cells were monitored. When 3.0% (wt/wt) lactic acid, pH 2.4, was inoculated with E. coli O157:H7 (approximately 6 log CFU/ml), viable microorganisms were recovered after a 20-min exposure to the acid. After 20 min in 1.0% (wt/wt) trisodium phosphate, pH 12.0, no viable E. coli O157:H7 microorganisms were detected. Exposure of E. coli O157:H7 to sodium metasilicate (5 to 10 s) at concentrations as low as 0.6%, pH 12.1, resulted in 100% inhibition with no recoverable E. coli O157:H7. No difference in inhibition profiles was detected between the E. coli O157:H7 and generic strains, suggesting that nonpathogenic strains may be used for in-plant sodium metasilicate studies.

Effect of Simulated Spray Chilling with Chemical Solutions on Acid-Habituated and Non–Acid-Habituated Escherichia coli O157:H7 Cells Attached to Beef Carcass Tissue

2004 ◽  
Vol 67 (10) ◽  
pp. 2099-2106 ◽  
Author(s):  
J. D. STOPFORTH ◽  
Y. YOON ◽  
K. E. BELK ◽  
J. A. SCANGA ◽  
P. A. KENDALL ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Lactic Acid ◽  
Cold Water ◽  
Phase 1 ◽  
Sodium Chlorite ◽  
Escherichia Coli O157 ◽  
Phase 2 ◽  
E Coli ◽  
Chemical Solutions ◽  
Beef Carcass

Samples (10 by 20 by 2.5 cm) of beef carcass tissue were inoculated (104 to 105 CFU/cm2) with Escherichia coli O157: H7 that was either non–acid habituated (prepared by incubating at 15°C for 48 h in inoculated filter-sterilized composite [1:1] of hot and cold water meat decontamination runoff fluids, pH 6.05) or acid habituated (prepared in inoculated water fluids mixed with filter-sterilized 2% lactic acid [LA] runoff fluids in a proportion of 1/99 [vol/vol], pH 4.12). The inoculated surfaces were exposed to conditions simulating carcass chilling (−3°C for 10 h followed by 38 h at 1°C). Treatments applied to samples (between 0 and 10 h) during chilling included the following: (i) no spraying (NT) or spraying (for 30 s every 30 min) with (ii) water, (iii) cetylpyridinium chloride (CPC; 0.1 or 0.5%), (iv) ammonium hydroxide (AH; 0.05%), (v) lactic acid (LA; 2%), (vi) acidified sodium chlorite (ASC; 0.12%), (vii) peroxyacetic acid (PAA; 0.02%), (viii) sodium hydroxide (SH; 0.01%), or (ix) sodium hypochlorite (SC; 0.005%) solutions of 4°C. Samples were taken at 0, 10, 24, 36, and 48 h of the chilling process to determine changes in E. coli O157:H7 populations. Phase 1 tested water, SH, PAA, LA, and 0.5% CPC on meat inoculated with non–acid-habituated pathogen populations, whereas phase 2 tested water, SC, AH, ASC, LA, and 0.1% CPC on meat inoculated with acid- and non–acid-habituated populations. Reductions in non–acid-habituated E. coli O157:H7 populations from phase 1 increased in the order NT = water = SH < PAA < LA < CPC. Reductions from phase 2 for acid-habituated cells increased in the order NT = water = SC < ASC = LA = AH < CPC, whereas on non–acid-habituated cells the order observed was NT = water = SC < AH = ASC < LA < CPC. Previous acid habituation of E. coli O157:H7 inocula rendered the cells more resistant to the effects of spray chilling, especially with acid; however, the trend of reduction remained spray chilling with water = non–spray chilling < spray chilling with chemical solutions.

Identification of Escherichia coli O157:H7 Meat Processing Indicators for Fresh Meat through Comparison of the Effects of Selected Antimicrobial Interventions

2005 ◽  
Vol 68 (12) ◽  
pp. 2580-2586 ◽  
Author(s):  
K. M. MARSHALL ◽  
S. E. NIEBUHR ◽  
G. R. ACUFF ◽  
L. M. LUCIA ◽  
J. S. DICKSON
Keyword(s):  
Escherichia Coli ◽  
Lactic Acid ◽  
Beef Cattle ◽  
Tissue Sample ◽  
Tissue Type ◽  
Escherichia Coli O157 ◽  
Fresh Meat ◽  
E Coli ◽  
The Mean ◽  
Beef Carcass

Fresh meat products can become contaminated with the pathogen Escherichia coli O157:H7 during the slaughter process; therefore, an E. coli O157:H7 indicator to verify the effectiveness of process controls in slaughter establishments would be extremely useful. The hides of 20 beef cattle were sampled, and 113 bacterial isolates were obtained. Thirteen of these isolates representing four genera, Escherichia, Enterobacter, Providencia, and Serratia, were selected based on growth and biochemical characteristics similar to those of five clinical strains of E. coli O157:H7. The temperature sensitivity was determined for the individual isolates and the five E. coli O157:H7 strains at 55 and 65°C. D65-values for all 13 isolates were not significantly different from D65-values of the E. coli O157:H7 strains. E. coli isolates were the only isolates whose D55-values were not significantly different from those of the E. coli O157:H7 strains. E. coli isolates P3 and P68 were more resistant to the effects of 55°C than were the other E. coli isolates but were not significantly different from E. coli O157:H7 WS 3331 (P > 0.05). The remaining E. coli isolates (P1, P8, and P14) were not significantly different from E. coli O157:H7 strains ATCC 35150, ATCC 43894, ATCC 43895, and WS 3062 (P > 0.05). Prerigor lean and adipose beef carcass tissue was artificially contaminated with stationary-phase cultures of the five E. coli beef cattle isolates or a cocktail of five E. coli O157:H7 strains in a fecal inoculum. Each tissue sample was processed with the following microbial interventions: 90°C water; 90°C water followed by 55°C 2% lactic acid; 90°C water followed by 20°C 2% lactic acid; 20°C water followed by 20°C 2% lactic acid; 20°C water followed by 20°C 20 ppm chlorine; and 20°C water followed by 20°C 10% trisodium phosphate. The appropriateness of the E. coli isolates as potential E. coli O157:H7 indicators was dependent upon the microbial intervention utilized. For all microbial intervention methods applied irrespective of tissue type, the mean log reductions of at least two E. coli isolates were not significantly different from the mean log reduction of the E. coli O157:H7 cocktail (P > 0.05). Because of the frequent employment of multiple microbial interventions in the cattle industry, no single isolate can realistically represent the effectiveness of all microbial interventions for reduction of E. coli O157:H7. Thus, the use of a combination of E. coli isolates may be required to accurately predict the effectiveness of microbial intervention methods on the reduction of E. coli O157: H7 in beef carcass tissue.

Long-Term Effect of Alkaline, Organic Acid, or Hot Water Washes on the Microbial Profile of Refrigerated Beef Contaminated with Bacterial Pathogens after Washing†

1998 ◽  
Vol 61 (3) ◽  
pp. 300-306 ◽  
Author(s):  
WARREN J. DORSA ◽  
CATHERINE N. CUTTER ◽  
GREGORY R. SIRAGUSA
Keyword(s):  
Acetic Acid ◽  
Lactic Acid ◽  
Growth Suppression ◽  
Hot Water ◽  
Trisodium Phosphate ◽  
Clostridium Sporogenes ◽  
Bacterial Populations ◽  
Microbial Profile ◽  
Subsequent Storage ◽  
Beef Carcass

The effect of 2% (vol/vol) lactic acid, 2% (vol/vol) acetic acid, 12% (wt/vol) trisodium phosphate, water at 72°C and water at 32°C washes on bacterial populations introduced onto beef carcass surfaces after treatment was determined for up to 21 days at 4°C in storage in vacuum packaging. Beef carcass short plates were collected from cattle immediately after slaughter and subjected to the above treatments or left untreated (C). Short plates were then inoculated with low levels (ca. <2 log10) of Listeria innocua, Salmonella typhimurium, Escherichia coli O157:H7, and Clostridium sporogenes cells contained in a bovine fecal cocktail. In general, growth of these four bacteria and of aerobic bacteria, lactic acid bacteria, and pseudomonads was suppressed or not observed when lactic acid or acetic acid treatments were used. Bacteria introduced to trisodium phosphate-treated tissue underwent some growth suppression, but to a lesser extent than on acid-treated tissue, and in some cases grew as well as on untreated beef surfaces. Water washes at 72 or 32°C offered little growth suppression of pathogens during subsequent storage when these bacteria were introduced to beef tissue after treatment. The use of a final lactic or acetic acid wash during the Processing of beef carcasses offers some residual efficacy in suppressing pathogen proliferation during refrigerated storage, should these bacteria be introduced immediately after carcass processing.

A Representative Microbial Sampling Method for Large Commercial Containers of Raw Beef Based on Purge†

1998 ◽  
Vol 61 (2) ◽  
pp. 162-165 ◽  
Author(s):  
WARREN J. DORSA ◽  
GREGORY R. SIRAGUSA
Keyword(s):  
Escherichia Coli ◽  
Sampling Method ◽  
Aerobic Bacteria ◽  
Escherichia Coli O157 ◽  
Antibiotic Resistant ◽  
E Coli ◽  
The Third ◽  
Core Samples ◽  
Bovine Feces ◽  
Microbial Sampling

The purge from beef combos (a boxed collection of beef trimmings) was tested as a means of representatively sampling the microbial content of this raw product. In the first experiment, purge was sampled from model beef combos that had been inoculated with bovine feces. Data from this experiment indicated a strong correlation (r = 0.94) between the total aerobic bacteria counts derived from the purge samples of a model beef combo and the total aerobic bacteria present in a rinse sample of the entire model beef combo. In a second experiment, two 500-g meat pieces were inoculated with an antibiotic-resistant Escherichia coli O157:H7 and placed at various levels within a 75-cm meat column. The marked bacteria were retrievable from the purge of the meat column after 24 h, showing that bacteria are carried downward into the purge. During the third part of the study, 90 beef combos (~900 kg beef/combo) were randomly selected at the receiving dock of a commercial grinding facility and sampled using both purge and concurrently used 11-g core samples. Purge samples from these combos recovered significantly greater numbers of mesophilic and psychrotrophic aerobic bacteria, coliforms, and E. coli than core samples from the same combos. Additionally, coliforms and E. coli were recoverable from 100% and 80%, respectively, of the purge samples taken, whereas core samples were only able to recover 60% and 40%, respectively, from the same combos. These findings indicate that a purge sample from a beef combo is a more efficacious sampling method for determining the general bacterial profile and identifying the presence of coliforms and E. coli than randomly taken core samples.

scholarly journals Molecular Identification of Lactic Acid Bacteria Approach to Sustainable food Security

2021 ◽  
Author(s):  
Dessy Abdullah ◽  
Sandeep Poddar ◽  
Ramesh Prasath Rai ◽  
Endang Purwati ◽  
Nadia Purnama Dewi ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Antimicrobial Activity ◽  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Listeria Innocua ◽  
Rrna Gene ◽  
Escherichia Coli O157 ◽  
Clear Zone ◽  
West Sumatra

Background: Dadiah is a traditional dish from West Sumatra made from buffalo milk, which is fermented in bamboo tubes and left at room temperature for ±2 days. Dadiah is included in the staple food category because it contains Lactic Acid Bacteria (LAB) which has the potential to be a probiotic. This study aims to determine the identification and characterization of LAB from Dadiah from Halaban, Kab. Fifty Cities, West Sumatra. Design and Methods: A survey method was used in this research with a descriptive analysis, Antimicrobial activity testing was done with bacteria Escherichia coli O157, Staphylococcus aureus, Listeria monocytogenes, and Listeria innocua. Molecular identification was done using the 16S rRNA gene. Results: Probiotic candidate test with the best results in testing for resistance to stomach acid at pH3 with the viability of 65.98%, bile salt resistance 0.3%, viability of 54.90% from 2DA isolates. Antimicrobial activity with the best clear zone area results was obtained in 2DA isolates with Escherichia coli O157 test bacteria of 21.16 mm, Staphylococcus aureus with a clear zone area of 23.17 mm, Listeria innocua of 19.24 mm and Listeria monocytogenes with a clear zone area 18.23 mm in 4DA isolate, LAB identification using 16S sRNA gene, results of running PCR base length 1419bp. Conclusions: Phylogenetic analysis shows that Dadiah of Limapuluh Kota Regency is a kin to Lactobacillus plantarum. The superiority of identification technology by using 16S rRNA gene only can be conducted if the nucleotide sequence information of the targeted bacteria is known beforehand.

Validation of Methods Used To Recover Escherichia coli O157:H7 and Salmonella spp. Subjected to Stress Conditions†

2001 ◽  
Vol 64 (10) ◽  
pp. 1466-1471 ◽  
Author(s):  
M. M. BRASHEARS ◽  
A. AMEZQUITA ◽  
J. STRATTON
Keyword(s):  
Escherichia Coli ◽  
Lactic Acid ◽  
Acid Stress ◽  
Stress Conditions ◽  
Escherichia Coli O157 ◽  
Salmonella Spp ◽  
Antibiotic Resistant ◽  
E Coli ◽  
Resistant Strains ◽  
Stressed Cells

Escherichia coli O157:H7, Salmonella spp., and Salmonella Typhimurium DT104 were stressed with lactic acid and cell-free supernatants from lactic acid bacteria and plated on three different media to determine if injured cells were recovered. A comparison of the susceptibility and recovery of antibiotic-resistant strains of the pathogens and nonresistant strains was also made. Acid stress conditions were created by adjusting the pH of a cocktail mixture (two to four strains) of the pathogen to 3.50 with lactic acid and holding for 18 h. The pathogen cocktail was also stressed with a cell-free supernatant of Lactobacillus lactis (pH 3.90) in a 4:6 ratio. Both nonstressed and stressed cocktail cultures were plated on Trypticase soy agar (TSA) and violet red bile agar (VRBA) for E. coli and xylose lysine tergitol4 (XLT4) for Salmonella. Repair of injured cells was evaluated by pour plating the stressed cells on a 5-ml thin layer of TSA and allowing a 2-h room temperature incubation followed by overlaying with VRBA or XLT4. There were significant reductions in the populations of both pathogens under both stress conditions when plating was done on nonselective media. Injured E. coli O157:H7 was not recovered on recovery or selective media compared with TSA. Numbers of cells of supernatant-stressed Salmonella spp. plated on selective and recovery media were similar to those on TSA. Acid-stressed cells for all Salmonella spp. were not recovered on TSA, selective, or recovery media at levels comparable to recovery on TSA. Antibiotic-resistant strains showed similar recovery patterns on all media evaluated. However, the antibiotic-resistant strains were less sensitive to both stress conditions. The use of antibiotic-resistant strains resulted in a greater recovery of stressed pathogens than the use of recovery media.

scholarly journals Treatments Using Hot Water Instead of Lactic Acid Reduce Levels of Aerobic Bacteria and Enterobacteriaceae and Reduce the Prevalence of Escherichia coli O157:H7 on Preevisceration Beef Carcasses†

2006 ◽  
Vol 69 (8) ◽  
pp. 1808-1813 ◽  
Author(s):  
JOSEPH M. BOSILEVAC ◽  
XIANGWU NOU ◽  
GENEVIEVE A. BARKOCY-GALLAGHER ◽  
TERRANCE M. ARTHUR ◽  
MOHAMMAD KOOHMARAIE
Keyword(s):  
Escherichia Coli ◽  
Lactic Acid ◽  
Hot Water ◽  
Aerobic Bacteria ◽  
Escherichia Coli O157 ◽  
E Coli ◽  
Beef Carcasses ◽  
Plate Counts ◽  
Water Treatments ◽  
Better Than

Lactic acid has become the most commonly used organic acid for treatment of postevisceration beef carcasses. Many processors have also implemented 2% lactic acid washes on preevisceration carcasses. We previously demonstrated that hot water washing and steam vacuuming are effective carcass interventions. Because of the effectiveness of hot water, we compared its use with that of lactic acid as a preevisceration wash in a commercial setting. A commercial hot water carcass wash cabinet applying 74°C (165°F) water for 5.5 s reduced both aerobic plate counts and Enterobacteriaceae counts by 2.7 log CFU/100 cm2 on preevisceration carcasses. A commercial lactic acid spray cabinet that applied 2% l-lactic acid at approximately 42°C (105 to 110°F) to preevisceration carcasses reduced aerobic plate counts by 1.6 log CFU/100 cm2 and Enterobacteriaceae counts by 1.0 log CFU/100 cm2. When the two cabinets were in use sequentially, i.e., hot water followed by lactic acid, aerobic plate counts were reduced by 2.2 log CFU/100 cm2 and Enterobacteriaceae counts were reduced by 2.5 log CFU/100 cm2. Hot water treatments reduced Escherichia coli O157:H7 prevalence by 81%, and lactic acid treatments reduced E. coli O157:H7 prevalence by 35%, but the two treatments in combination produced a 79% reduction in E. coli O157:H7, a result that was no better than that achieved with hot water alone. These results suggest that hot water would be more beneficial than lactic acid for decontamination of preevisceration beef carcasses.

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