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This study compares the efficacy of commercial antimicrobials to inactivate unstressed and stress-adapted Campylobacter jejuni on broiler wings using immersion and electrostatic spray and evaluates the economic feasibility of the two methods. Overnight cultures (18 h) were prepared from three strains of C. jejuni that were either unstressed, acid stressed (AS, 2 h in pH 5 Bolton broth), starvation stressed (SS, 2 h in 0.9% saline solution), or cold stressed (CS, 5 days in Bolton broth at 4 °C). Unstressed or stress-adapted C. jejuni cells were inoculated onto fresh chicken wings, which were kept untreated (control), immersed in or electrostatically sprayed with peroxyacetic acid (PAA-0.1%), lactic acid (LA-5%), lactic and citric acid blend (LCA-2.5%), sodium hypochlorite (SH-70 ppm), or a mixture of PAA-H2O2 (SaniDate®-5.0, SD-0.25%) for 30 s. Surviving bacteria were recovered onto Brucella agar under microaerophilic conditions. Economic feasibility analysis was performed based on the assumption of ∼1500 wings annually from very small poultry plants. There was no difference in the inactivation of C. jejuni cells between immersion and electrostatic spray (P > 0.05). Cross-protection was developed in AS (0.1–0.6 log CFU/g) and SS (0.8–1.8 log CFU/g) samples that affected pathogen recovery during subsequent exposure to antimicrobials by immersion or electrostatic spray. Among all stressed cultures, different degrees of inactivation (P

This study was conducted to compare the efficacy of antimicrobials sprayed by electrostatic versus conventional sprayer for inactivation of Salmonella, Listeria monocytogenes, and Campylobacter jejuni on eggs and to determine the economic feasibility of these treatments. Eggs were dip inoculated with overnight cultures (18 h) of Salmonella Typhimurium, Salmonella Tennessee, a two-strain mixture of L. monocytogenes, and a three-strain mixture of C. jejuni (microaerophilic condition). Inoculated eggs were then not sprayed or subjected to electrostatic and conventional spraying with peroxyacetic acid (PAA; 0.1%), lactic acid (5.0%), lactic and citric acid blend (2.5%), sodium hypochlorite (SH; 50 ppm), and SaniDate-5.0 (SD [a mixture of PAA and H2O2]; 0.25%) for 30 s (15 s each side). Surviving bacteria on eggshells were recovered on xylose lysine Tergitol 4 agar ( Salmonella), modified Oxford agar ( L. monocytogenes), or Brucella agar ( C. jejuni). Compared with conventional spraying, electrostatic spraying of PAA, SD, and SH achieved significant additional reductions ( P < 0.05) of Salmonella, L. monocytogenes, and C. jejuni of 0.96 to 3.18, 1.19 to 3.05, and 0.96 to 1.62 log CFU per egg, respectively. A simple cost comparison suggests that regardless of the antimicrobial agent used, the cost of using an electrostatic sprayer is 20 to 40% lower than that of a conventional sprayer for a small poultry farm that produces 1,500 eggs per day. Among the five antimicrobials, the total sanitizing cost was lowest for SH, followed by PAA and SD. The results indicated that electrostatic spraying of commercial antimicrobials can be considered an effective and economical approach to enhancing the microbial safety of eggs, especially for small poultry processors.

Three-step wash with commercial antimicrobials including a H2O2-peroxyacetic-acid mixer, chlorine water and a lactic/citric acid blend was conducted to inactivate foodborne pathogens on spinaches. Fresh spinaches from West Virginia small growers were artificially contaminated with a 4-strain mixture of Salmonella and Listeria monocytogenes. Inoculated spinaches were three-step washed in water, antimicrobial, and water (WAW) or in water, water, and antimicrobial (WWA) with 10 s of each step. Antimicrobial treatments are sodium hypochlorite (SH; 100 ppm, pH-6.8), lactic/citric acid blend (LCA; 2.5%), and a H2O2-peroxyacetic-acid mixer (SaniDate-5.0, 0.0064, 0.25 and 0.50%). Microbial populations were analyzed on XLT-4 (Salmonella) and MOX agars (L. monocytogenes) with a total of 9 samples (3 replicates) followed by analyzed using SAS (Mixed Model Procedure, P = 0.05). Unwashed spinaches recovered 4.57–5.10 and 6.68–6.73 log10 CFU/g of Salmonella and L. monocytogenes, respectively. WWA procedure obtained additional reductions of the pathogens by 0.35–1.07 log10 CFU/g (LsMeans) than the WAW procedure. Three-step wash in 0.25% and 0.50% of SaniDate-5.0 solution showed at least similar or even greater (P

This study compares kinetic parameters of Salmonella and Enterococcus faecium in moisture enhanced, reconstructed comminuted chicken patties prepared with different pump rates during double pan-broiling with various set-up temperatures. Fresh 1.5-kg chicken breast meat was course grounded, inoculated with S. Typhimurium and Tennessee, or E. faecium, followed by adding NaCl (2.0%) + Na-tripolyphosphate (0.5%) solutions to achieve pump rates of 1%, 5%, or 11.1%. Meat samples were manually manufactured into patties with the thickness of 2.1 cm and diameter of 10.4 cm. Patties were packaged with polyvinyl chloride films in the foam-tray stored at 4°C for 42 h before double pan-broiling set at 200°, 300°, or 425°F for 0 to 420 s. Counts of pathogens were analyzed on xylose-lysine-Tergitol-4 and bile esculin agars with tryptic soy agar layers. Microbial data and kinetic parameters (n = 9, United States Department of Agriculture [USDA]-Integrated-Predictive-Modeling-Program/USDA-Global-Fit software) were analyzed by the Mixed Model Procedure (SAS). Double pan-broiling reduced >5-log10 CFU/g (P < 0.05) of Salmonella after 360 (200°F), 180 to 225 (300°F), and 150 to 165s (425°F), and of E. faecium after 270 s (300°F), and 180 s (425°F) across all samples. D-values (Mafart-Weibull model) of Salmonella and E. faecium in 1% moisture enhanced samples cooked at 200 to 425°F (102.7–248.2 and 115.5–271.0 s) were lower (P < 0.05) than 11.1% samples (119.8–263.7 and 122.5–298.3 s). Salmonella were more susceptible (P < 0.05) to heat than E. faecium. “Shoulder-time” (Buchanan-Two-Phase model) of Salmonella cooking at 200° to 425°F increased (P < 0.05) from 82.3–229.0 to 116.6–246.2 s as pump rate increased from 1 to 11.1%, whereas this phenomenon was not shown for E. faecium. Results indicate that Salmonella were resistant to heat in chicken patties with greater pump rate. E. faecium can be used as a surrogate for Salmonella to validate thermal inactivation in chicken products.

This study was designed to evaluate two triple-wash procedures with commercial antimicrobials to inactivate foodborne pathogens and surrogate bacteria on cucumbers and tomatoes. Fresh, West Virginia locally grown cucumbers and tomatoes were dip-inoculated with Salmonella Typhimurium and Tennessee, Listeria monocytogenes (3-strain), and Enterococcus faecium. Produce was washed through two triple-wash steps (10 s each) including water dip, antimicrobial dip, and water dip (WAW), or water dip, water dip, and antimicrobial dip (WWA), followed by draining (2 min) on aluminum foil. A triple-water (WWW) process was also included as a water-only control. Tested treatments were (1) water; (2) sodium hypochlorite (SH, 100 ppm, pH 8.2); (3) acidified sodium hypochlorite (ASH, 100 ppm, pH 6.8 adjusted by citric acid); (4) lactic and citric acid blend (LCA, 2.5%); and (5) a H2O2-peroxyacetic acid mix [SaniDate-5.0 (SD) 0.0064, 0.25, and 0.50%]. Surviving bacteria were recovered on xylose lysine tergitol-4 (XLT-4, Salmonella), Modified Oxford (MOX, L. monocytogenes), and bile esculin agar (E. faecium). Data (two replicates, four samples/replicate) were analyzed using the mixed model procedure of SAS (P = 0.05). Counts of Salmonella, L. monocytogenes, and E. faecium on unwashed cucumbers and tomatoes were 5.42–6.23, 6.31–6.92, and 6.05 log colony-forming units (CFU)/produce, respectively. Triple-wash with water only reduced all three tested bacteria by 0.45–1.36 log CFU/fruit. Triple-wash by WWA with antimicrobials achieved additional reductions [least squares means (LsMeans)] of 0.38 log CFU/cucumber (Salmonella), 0.56 log CFU/cucumber (E. faecium), 1.48 log CFU/tomato (Salmonella), 1.09 log CFU/tomato (L. monocytogenes), and 0.71 log CFU/tomato more than the WAW procedure. Applying SD-0.25 and SD-0.50% solutions in triple-washing cucumbers and tomatoes resulted in reductions (P > 0.05) similar to ASH and greater reductions (P < 0.05) than SH and LCA. E. faecium was less susceptible (P < 0.05) or there was no difference (P > 0.05) in comparison with Salmonella in most cases, except for tomatoes treated with WWA. The results of this study indicate that SD could be used as an alternative antimicrobial agent for chlorine water in triple-wash processing at local small produce plants. Future pilot plant validation studies and cost-effectiveness analyses are needed for applying SD solutions in triple-wash by WV local small produce growers.

This study aims to evaluate the microbiological quality and efficacy of antimicrobials to inactivate unstressed or cold-stress adapted Salmonella and Enterococcus on broiler carcasses and wings processed at a small USDA-inspected slaughter facility in West Virginia. The first part of the study included 42 carcasses that were pre- and secondarily-enriched in bacterial media followed by streak-plating onto XLT-4 and HardyCHROM™-agar Salmonella and confirmation using an API20E-kit. The aerobic plate counts (APC), Escherichia coli (ECC), total coliforms (TCC), and yeast/molds were analyzed on petri-films. The second part of the study included fresh broiler carcasses and wings that were inoculated with unstressed and cold-stress-adapted (4 °C, 7-day) Salmonella Typhimurium and Tennessee, and Enterococcus faecium ATCC 8459 (5.5 to 6.0 log10CFU/mL) and later dipped into peroxyacetic acid (PAA; 1,000 ppm), lactic acid (LA; 5%), lactic and citric acid blend (LCA; 2.5%), and sodium hypochlorite (SH; 70 ppm) for 30 s without (carcasses) or with 2-min drainage (wings). The surviving bacteria were recovered onto non-selective and selective agar to analyze the total microbial population, Salmonella and Enterococcus. APC, TCC, and Yeast/Molds were 2.62, 1.08, and 2.37 log10CFU/mL on broiler carcasses, respectively. A total of 30 and 40% of the carcasses tested positive for Salmonella spp. and E. coli (0.48 to 1.70 log10CFU/mL), respectively. For carcasses, antimicrobial reductions of cold-stress-adapted cells of Salmonella and Enterococcus were greater (P 0.05) than the unstressed cells. For wings, cold-stress-adapted Salmonella were more (P 0.05) sensitive to antimicrobials than unstressed cells; however, unstressed and cold-stress-adapted Enterococcus behaved similarly (P 0.05). The reduction of Salmonella and Enterococcus on carcasses and wings increased in the order of SH ≤ LCALAPAA and irrespective of unstressed or cold-stress-adapted cells. Applying post-chilling antimicrobial dipping treatments could be an intervention approach to control Salmonella on locally processed broilers. In addition, Enterococcus faecium could be a Salmonella surrogate for in-plant validation studies.

This study aimed to evaluate the microbiological quality/safety of fresh produce from farmers’ markets (FM) and assess the post-harvest washing practice with antimicrobials to inactivate Salmonella and Listeria monocytogenes on fresh produce. In study I, 212 produce samples were tested for the presence of Salmonella and Listeria spp. using modified FDA-BAM methods. Aerobic plate counts (APCs), total coliforms (TCCs), and yeast/molds were analyzed on petri-films. Among the 212 samples, the APCs, TCCs, and yeast/molds were 3.72–5.63, 3.67–5.47, and 3.07–4.13 log CFU/g, respectively, with spinach containing the highest ( P Salmonella enterica spp. enterica was detected on 18.6% of spinach, 10.9% of tomatoes, 18.5% of peppers, and 56.3% of cantaloupes, which is much higher than previous reported. Only 3.78% of the samples were confirmed for Listeria spp., and 50% of them were identified as L. monocytogenes , based on multiplex PCR results. Due to the high percentage of pathogens detected on the farmers marker produce an evaluation of post-harvest produce washing with various antimicrobials was conducted in study II. Specifically, spinach, tomatoes, green peppers and cucumbers were inoculated with S . Typhimurium and Tennessee or L. monocytogenes and washed in tap water, vinegar water (10%), lactic acid (5%), a lactic and citric acid blend (2.5%), and sodium hypochlorite (200 ppm) for 30 s or unwashed. Vinegar water (10%) showed better ( P S. Typhimurium and Tennessee on tomatoes and cucumbers, and L. monocytogenes on tomatoes and peppers than tap water. The three antimicrobials reached an additional reduction level of 0.9–2.7 ( S. Typhimurium and Tennessee) and 0.2 to 1.4 log CFU/g ( L . monocytogenes ) compared to tap water. Lactic acid indicated the best ( P S. Typhimurium and Tennessee on spinach and green peppers, and sodium hypochlorite showed the best ( P L. monocytogenes on cucumbers. The results supplied important information for FM vendors to develop post-harvest protocols to control foodborne pathogens.

This study aimed to evaluate the thermal inactivation of Campylobacter jejuni in moisture enhanced reconstructed non-intact chicken patties with various pump rates and double pan-broiled at different temperatures. Fresh 1.5-kg coarse-ground chicken breast, inoculated with C. jejuni (3-strain mixture), were moisture enhanced with NaCl (2.0%) + Na-tripolyphosphate (0.5%) solutions to reach 1.0%, 5.0% or 11.0% pump rates. Inoculated samples were then manufactured into patties (2.1 cm thick and 10.4 cm diameter) followed by aerobic storage at 40.1 °F for 42.0 h before double pan-broiling for 0.0–360.0 s with temperatures set at 200.0, 300.0, 400.0 or 425.0 °F. C. jejuni counts were analyzed on Brucella agars under microaerophilic condition. Cooking reduced (P

This study aims to i) evaluate two triple-wash procedures with an H2O2-peroxyacetic-acid mixer (SaniDate-5.0) to improve microbial safety and quality of butternut squashes and ii) determine the feasibility of the triple-wash application in a processing plant. In study I, fresh squashes were dip-inoculated with a mixture of Salmonella and Listeria monocytogenes, followed by two triple-wash steps including water dip-antimicrobial dip-water dip (WAW) or water dip-water dip-antimicrobial dip (WWA). Tested antimicrobials were i) lactic/citric acid blend (LCA; 2.5%); ii) sodium hypochlorite (SH; 100 ppm); and iii) SaniDate-5.0, 0.0064, 0.25 and 0.50%. Surviving bacteria were recovered using XLT-4 agar for Salmonella and MOX agar for L. monocytogenes. In study II, freshly harvested squashes were either left unwashed or triple-washed using WWA in water and SaniDate-5.0 (0.0071 and 0.45%) at a processing plant followed by storage at 9 °C for 70 days. Aerobic Plate Counts (APCs), coliforms/Escherichia coli, lactic-acid-bacteria, and psychrotrophs on squashes were tested every seven days. Counts of Salmonella and L. monocytogenes on unwashed squash were 5.0–5.3 and 5.4–6.0 log CFU/squash, respectively. WWA wash was more effective (P

This study compared the quality variation and thermal inactivation of Escherichia coli O157:H7 in non-intact beef and veal. Coarse ground beef and veal patties (2.1 cm thick, 12.4 cm diameter, 180 g) inoculated with E. coli O157:H7, aerobically stored before double pan-broiling for 0–360 s without rest or to 55, 62.5, 71.1, and 76 °C (internal temperature) with 0.5- or 3.5-min rest. Microbial population and qualities including color, cooking losses, pH, water activity, fat, and moisture content, were tested. After cooking the beef and veal patties, the weight losses were 17.83–29%, the pH increased from 5.53–5.60 to 5.74–6.09, the moisture content decreased from 70.53–76.02% to 62.60–67.07%, and the fat content increased (p < 0.05) from 2.19–6.46% to 2.92–9.45%. Cooking beef and veal samples with increasing internal temperatures decreased a* and b* values and increased the L* value. Escherichia coli O157:H7 was more sensitive to heat in veal compared to beef with shorter D-value and “shoulder” time. Cooking to 71.1 and 76 °C reduced E. coli O157:H7 by >6 log CFU/g regardless of rest time. Cooking to 55 °C and 62.5 °C with a 3.5-min rest achieved an additional 1–3 log CFU/g reduction compared to the 0.5-min rest. Results should be useful for developing risk assessment of non-intact beef and veal products.

The small-scale mobile poultry-processing unit (MPPU) produced raw poultry products are of particular food safety concern due to exemption of USDA poultry products inspection act. Limited studies reported the microbial quality and safety of MPPU-processed poultry carcasses. This study evaluated the Salmonella and Campylobacter prevalence in broiler ceca and on MPPU-processed carcasses and efficacy of commercial antimicrobials against Campylobacter jejuni on broilers. In study I, straight-run Hubbard × Cobb broilers (147) were reared for 38 days on clean-shavings (CS, 75) or built-up-litter (BUL, 72) and processed at an MPPU. Aerobic plate counts (APCs), coliforms, Escherichia coli, and yeast/molds (Y/M) of carcasses were analyzed on petrifilms. Ceca and carcass samples underwent microbial analyses for Salmonella and Campylobacter spp. using the modified USDA method and confirmed by API-20e test (Salmonella), latex agglutination immunoassay (Campylobacter), and Gram staining (Campylobacter). Quantitative polymerase chain reaction (CadF gene) identified the prevalence of C. jejuni and Campylobacter coli in ceca and on carcasses. In study II, fresh chilled broiler carcasses were spot inoculated with C. jejuni (4.5 log10 CFU/mL) and then undipped, or dipped into peroxyacetic acid (PAA) (1,000 ppm), lactic acid (5%), lactic and citric acid blend (2.5%), sodium hypochlorite (69 ppm), or a H2O2–PAA mix (SaniDate® 5.0, 0.25%) for 30 s. Surviving C. jejuni was recovered onto Brucella agar. APCs, coliforms, and E. coli populations were similar (P > 0.05) on CS and BUL carcasses. Carcasses of broilers raised on BUL contained a greater (P 0.05) in CS-treated ceca than BUL samples. Prevalence of Campylobacter spp., C. jejuni, and C. coli was not different (P > 0.05) on CS- and BUL-treated carcasses. All antimicrobials reduced C. jejuni by 1.2–2.0 log CFU/mL on carcasses compared with controls. Hence, raising broilers on CS and applying post-chilling antimicrobial treatment can reduce Salmonella and Campylobacter on MPPU-processed broiler carcasses.

The contamination of agricultural ground with estrogen compounds through application of animal wastes is a present concern. At the same time, current uses for waste fly ash having high carbon content are limited. To help mitigate these problems, we examine using waste fly ash as a useful adsorbent for Estradiol in pig waste digests. In this study, Estradiol was added to vials containing water and fly ash from several different power plants. After an extraction process, the amount of Estradiol in the water was measured. Commercial activated carbon was also used for comparison purposes. Vials containing varying concentrations of Estradiol and no trapping material were used as a control. The results from this study indicate that fly ash can be used as a trapping material for Estradiol in water, but that commercially available activated carbon can trap about an order of magnitude more Estradiol than the fly ash and that the effects of the fly ash matrix can both inhibit and promote the solvation of Estradiol into water depending possibly upon pH and cation concentration effects. In addition, preliminary extraction studies using pig waste digest indicate that fly ash can be used as adsorbent for Estradiol present in pig waste.

Free chlorine (FC) reacting with organic matter in wash water promotes the formation of chlorine by-products. This study aims to evaluate the dynamic impact of FC and organic load on the generation of haloacetic acids (HAAs) and trihalomethanes (THMs) in simulated wash water. Lettuce juice was sequentially added into FC solution with FC periodically replenished. Water samples were collected after each lettuce juice addition to measure water qualities and determine HAAs and THMs using US-Environmental-Protection-Agency (EPA) methods. Concentrations of 88–2103 μg/l of total HAAs and 20.79–859.47 μg/l of total THMs were detected during the study. Monobromoacetic, tribromoacetic, chlorodibromoacetic and trichloroacetic acid were the major HAAs components. Chloroform (trichloromethane) was the primary THMs present. A significant correlation of HAAs with chemical oxygen demand and THMs with FC was observed. Results indicated that optimizing wash water sanitizing systems to limit organic matters and maintain minimal effective FC concentration is critical.