Impact of Interventions on the Survival of Salmonella enterica I 4,[5],1 2:i:- in Pork.

Abstract: A mixed culture of Salmonella enterica serovar I 4,[5],12:i:- isolates was compared with a mixed culture of reference Salmonella serovars and nonpathogenic Escherichia coli surrogates. The two groups of Salmonella were compared for their resistance to commonly used pork carcass interventions, survival in ground pork, and thermal resistance in ground pork. No differences in responses were observed between the two groups of Salmonella serovars and the nonpathogenic E.

Can supplemental nitrate in cured meats be used as a means of increasing residual and dietary nitrate and subsequent potential for physiological nitric oxide without affecting product properties?

The effects of formulated sodium nitrate plus supplemental nitrate (SN) from celery juice powder on residual nitrite, residual nitrate, rancidity, microbial growth, color, sensory properties, and proximate composition of frankfurters, cotto salami and boneless ham during storage (1°C) were studied. The products were assigned one of two treatments, which were each replicated twice: control (156ppm sodium nitrite) or SN (156ppm sodium nitrite and 1718ppm sodium nitrate in combination with 2% VegStable 502). Sensory parameters and proximate composition were measured once for each replication.

Late Cenozoic onset of the latitudinal diversity gradient of North American mammals.

The decline of species richness from equator to pole, or latitudinal diversity gradient (LDG), is nearly universal among clades of living organisms, yet whether it was such a pervasive pattern in the geologic past remains uncertain. Here, we calculate the strength of the LDG for terrestrial mammals in North America over the past 65 My, using 27,903 fossil occurrences of Cenozoic terrestrial mammals from western North America downloaded from the Paleobiology Database. Accounting for temporal and spatial variation in sampling, the LDG was substantially weaker than it is today for most of the Cenozoic and the robust modern LDG of North American mammals evolved only over the last 4 My.

Is It Time for a Broader Approach? Recasting the Value of "Employee Health" With a Focus on Workforce Capability.

A discussion about a value proposition for investment in employee health initiatives that necessitates a more comprehensive and multifaceted approach to optimizing the human capital within an organization.

Dissolved carbon dioxide and oxygen concentrations in purge of vacuum-packaged pork chops and the relationship to shelf life and models for estimating microbial populations.

The objectives of this study were to determine the dissolved CO2 and O2 concentrations in the purge of vacuum-packaged pork chops over a 60 day storage period, and to elucidate the relationship of dissolved CO2 and O2 to the microbial populations and shelf life. As the populations of spoilage bacteria increased, the dissolved CO2 increased and the dissolved O2 decreased in the purge. Lactic acid bacteria dominated the spoilage microflora, followed by Enterobacteriaceae and Brochothrix thermosphacta.

Transfer of methicillin-resistant Staphylococcus aureus from retail pork products onto food contact surfaces and the potential for consumer exposure.

Methicillin-resistant Staphylococcus aureus (MRSA) is a pathogen that has developed resistance to beta-lactam antibiotics and has been isolated at low population numbers in retail meat products. The objectives of this study were to estimate the potential transfer of MRSA from contaminated retail pork products to food contact surfaces and to estimate the potential for human exposure to MRSA by contact with those contaminated surfaces. Pork loins, bacon, and fresh pork sausage were inoculated with a four-strain mixed MRSA culture over a range of populations from approximately 4 to 8 log, vacuum packaged, and stored for 2 weeks at 5°C to simulate normal packaging and distribution.

The effect of pH and nitrite concentration on the antimicrobial impact of celery juice concentrate compared with conventional sodium nitrite on Listeria monocytogenes.

The objectives of this study were to evaluate the impact of pH and nitrite from celery juice concentrate (CJ) on the growth of Listeria monocytogenes in broth and on ham slices, and to evaluate the impact of pH and nitrite from CJ on quality attributes of the ham. The pH of both broth and ham were increased by the addition of CJ. The CJ was less effective than conventional nitrite at 100 mg/kg nitrite in broth, but in ham, the CJ treatments at both 100 and 200 mg/kg resulted in growth of L.

Inhibition of Listeria monocytogenes using natural antimicrobials in no-nitrate-or-nitrite-added ham.

Consumer demand for foods manufactured without the direct addition of chemical preservatives, such as sodium nitrite and organic acid salts, has resulted in a unique class of "naturally" cured meat products. Formulation with a natural nitrate source and nitrate-reducing bacteria results in naturally cured processed meats that possess traits similar to conventionally cured meats. However, previous research has shown that the naturally cured products are more susceptible to pathogen growth.

Antilisterial activity and consumer acceptance of irradiated chicken breast meat vacuum-infused with grape seed and green tea extracts and tartaric acid.

Contamination of poultry with pathogenic bacteria contributes to human foodborne disease, causes damage to industry brand names, and has a significant economic impact on the food industry in the form of both damage to industry brand names and losses associated with recalls. Irradiation is a safe and effective means of decontaminating poultry products, but the maximum dose strengths allowed negatively impact poultry sensory quality characteristics. The 1st objective of this study was to investigate the potential interactive inhibitory effects of natural antimicrobials as components of a vacuum-marination in addition to various dose levels of irradiation.

Evaluation of Escherichia coli biotype 1 as a surrogate for Escherichia coli O157:H7 for cooking, fermentation, freezing, and refrigerated storage in meat processes.

Five Escherichia coli biotype I isolates were compared with E. coli O157:H7 under four common meat processing conditions. The processes that were evaluated were freezing, refrigerating, fermentation, and thermal inactivation.

Evaluation of nonpathogenic surrogate bacteria as process validation indicators for Salmonella enterica for selected antimicrobial treatments, cold storage, and fermentation in meat.

Prerigor lean and adipose beef carcass tissues were artificially inoculated individually with stationary-phase cultures of five nonpathogenic Escherichia coli cultures that had been previously identified as surrogates for E. coli O157:H7 or a mixture of five Salmonella strains in a fecal inoculum. Each tissue sample was processed with microbial interventions comparable with those used in the meat industry.

Effect of gamma or beta radiation on Salmonella DT 104 in ground pork.

Mixtures of six Salmonella Typhimurium DT 104 strains were inoculated into three ground pork products to determine the effect of fat content on the radiation resistance of Salmonella DT 104. The ground pork products were 90% lean, 50:50 fat:lean, and 100% fat. Inoculated products were irradiated using a gamma radiation source in a self-contained 137Cesium irradiator or a 10 MeV accelerator producing electrons (e-beam).

Impact of the population of spoilage microflora on the growth of Listeria monocytogenes on frankfurters.

Approximately 100 CFU/cm2 of a five-strain mixture of Listeria monocytogenes was coinoculated onto frankfurters with three different concentrations (10(2), 10(4), and 106 CFU/cm2) of an undefined spoilage microflora derived from commercial frankfurters. The frankfurters were vacuum packaged and stored at 10 degrees C for up to 48 days. The populations of L.

Identification of Escherichia coli O157:H7 meat processing indicators for fresh meat through comparison of the effects of selected antimicrobial interventions.

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.

Survival of Listeria monocytogenes and Escherichia coli O157:H7 during sauerkraut fermentation.

Sauerkraut was produced from shredded cabbage, as is typical in the United States, and from whole head cabbages, which is a traditional process in parts of Eastern Europe. The sauerkraut was inoculated with five strain mixtures of Escherichia coli O157:H7 and Listeria monocytogenes, and the populations of these bacteria, as well as lactic acid bacteria, pH, and titratable acidity, were monitored over the course of fermentation. Fermentation variables were temperature (18 and 22 degrees C) and salt concentration (1.

Effect of electron beam irradiation and storage at 5 degrees C on thiobarbituric acid reactive substances and carbonyl contents in chicken breast meat infused with antioxidants and selected plant extracts.

This study evaluated the effectiveness of synthetic and natural antioxidants, green tea, commercial grape seed extracts/combinations, and TBHQ, with varying concentrations of lipid oxidation of nonirradiated and irradiated chicken breast meats stored at 5 degrees C for 12 days. Fresh boneless and skinless chicken breast meats were vacuum-infused with varying concentrations of antioxidants: green tea, grape seed extracts alone/in combination, and TBHQ. The irradiation dosage was 3.

Storage and packaging effects on sensory and color characteristics of ground beef.

Effects of irradiation (2 kGy) of ground beef patties from trimmings stored aerobically for 0 or 6 days on lean color, odor, and sensory attributes were investigated. Beef trimings were coarse ground and split into 2 groups. Group one was fine ground, pattied, and packaged immediately; group-two was stored 6 days then fine ground, pattied, and packaged.

Destruction of Bacillus anthracis strain Sterne 34F2 spores in postal envelopes by exposure to electron beam irradiation.

Aims: To determine the irradiation dose necessary to reduce the populations of Bacillus anthracis spores in a dry medium in postal envelopes.

Methods And Results: Bacillus anthracis Sterne 34F2 spores were dispersed in non-fat dry milk and then placed into standard business postal envelopes. The spores were treated with a sequence of irradiation doses to determine the decimal reduction value (D10) in kiloGrays (kGy).

Impact of pH enhancement on populations of Salmonella, Listeria monocytogenes, and Escherichia coli O157:H7 in boneless lean beef trimmings.

Boneless lean beef trimmings were inoculated with multiple strains of salmonellae, Listeria monocytogenes, and Escherichia coli O157:H7 at levels of ca. 6 log10 CFU/g. pH enhancement with ammonia gas was then used to increase the pH of the trimmings to ca.

Hot water and organic acid interventions to control microbiological contamination on hog carcasses during processing.

Pork skin and muscle tissue were washed with water at temperatures from 25 to 80 degrees C. Water temperatures of 65 and 80 degrees C resulted in greater population reductions of Enterobacteriaceae on pork muscle tissue than lower water temperatures. There was no observable effect of water temperature on population reductions of Enterobacteriaceae on pork skin.