Ground Turkey Meat Research Articles

Genetic characterization of blaCTX-M-65 in Salmonella Infantis and blaCMY-2 in Salmonella Heidelberg isolated from fresh ground turkey meat sold in supermarkets in Los Andes and San Felipe, Chile

Annually, food poisoning caused by non-typhoidal Salmonella (NTS) accounts for 40 million foodborne infections worldwide. Outbreaks due to multidrug-resistant NTS strains are associated with the consumption of poultry products. We aimed to determine the proportion of NTS in ground turkey meat available at supermarkets in two locations in Chile, characterizing their serovars, virulence traits, and antimicrobial resistance profiles. Between September and December 2018, we analyzed 47 samples of packed ground turkey meat purchased at 13 supermarkets. NTS were identified by MALDI-TOF, and antimicrobial susceptibility was determined by the disk-diffusion agar method. Whole genome sequencing was performed with MiSeq (Illumina) followed by Nullarbor analysis. NTS was detected in 6 out of 47 samples (12.8 %, 95 %CI: 6.0–25.1 %), identifying S. enterica serovar Infantis (n=4 isolates), serovar Agona (n=1 isolate), and serovar Heidelberg (n=1 isolate), respectively. S. Infantis belonged to sequence type (ST)32, differentiating two clones, whereas the S. Agona was ST13 and S. Heidelberg was ST15. S. Infantis strains were multidrug antibiotic resistant, harboring blaCTX-M-65, tetA, and mutations that confer fosfomycin resistance. Serovars Agona and Heidelberg showed tetracycline (tetB) and fosfomycin resistance (fosA7). Additionally, serovar Heidelberg showed resistance to sulfamethoxazole-trimethoprim, aminoglycosides, and carried the blaCMY-2 gene. This is the first report in Chile about NTS detected in raw ground turkey meat available in supermarkets. S. Infantis and S. Agona strains showed a phylogenetic relationship with strains of the same serovars isolated from the environment in our country. This situation would impact food poisoning and the dissemination of bacterial resistance between animals, humans, and the environment.

ВОЗМОЖНОСТЬ ИСПОЛЬЗОВАНИЯ ПОРТУЛАКА ОГОРОДНОГО (PORTULACA OLERACEA L.) ДЛЯ ОБОГАЩЕНИЯ МЯСНЫХ РУБЛЕНЫХ ИЗДЕЛИЙ

The purpose of the study is to identify the possibility of using the aerial part of purslane in cutlet recipes. Objectives: to determine the dosage of purslane in ground turkey meat, ensuring the best quality indicators of the product; to conduct a tasting assessment of the product; to develop a schematic diagram for the production of semi-finished meat and vegetable products. The components for the production of chopped semi-finished meat products complied with the regulatory documentation: turkey meat – in accordance with GOST R 55365-2012 “Mince meat. Technical conditions" and GOST 32951-2014 "Semi-finished meat and meat-containing products. General technical conditions"; chicken eggs – according to GOST 31654-2012 “Chicken eggs for food. Technical conditions"; onions – according to GOST 34306-2017 “Fresh onions. Technical conditions"; black pepper – according to GOST 29050-91 “Spices. Black and white pepper. Technical conditions"; table salt – according to GOST R 51574-2018; vegetable oil – according to GOST 1129-2013; breadcrumbs – according to GOST 28402-89. Organoleptic and tasting assessment of finished products was carried out in accordance with GOST 31986-2012 (GOST 7269-2015 and GOST 9959-2015) on a 5-point scale. A recipe was developed for turkey meat cutlets with the addition of a plant component – purslane. Purslane was collected in the vicinity of Krasnoyarsk and was added crushed to minced meat in dosages from 3 to 9 % in increments of 3 instead of raw meat. The study of the organoleptic characteristics of the finished minced meat product showed that the rational dosage introduced into the meat cutlet mass of the vegetable ingredient is 6 % of the mass of the minced meat. The test sample with the introduction of 6 % plant component received the highest rating from tasters. Stages for the production of cutlets have been developed with the addition of chopped aerial parts of purslane to the recipe. The use of purslane in the recipe for chopped semi-finished meat products will help expand the range of this type of product, improve the consumer properties of meat products, increase the content of essential components in the composition, and reduce costs.

Meat crust as a novel food ingredient to regulate lipid peroxidation and oxidative stress

Pan Fry (PF) is a common heating treatment however, there is limited data on meat oxidation after PF using direct contact with an uncoated iron pan. After PF, a crust is formed, and in this study, we aim to evaluate the potential anti-oxidation and anti-lipid peroxidation capacity of such crust. Ground beef and turkey meat were heat treated using PF or microwave. Lipid peroxidation was evaluated using malondialdehyde accumulation. PF meat generated lower lipid peroxidation levels versus microwave-heated meat. Iron PF has decreased lipid peroxidation versus Teflon pan heating. The crust significantly lowered lipid peroxidation and possessed millard reaction products (MRPs), strong reducing abilities, iodine removal capacity, and some iron chelation capacity. We demonstrated that the crust substantially decreases lipid peroxidation levels in various systems and can be used as a novel seminatural antioxidant ingredient, which may lead to extended shelf life and protects various food products.

Effect of pimenta essential oil against Salmonella Agona and Salmonella Saintpaul in ground turkey meat and nonprocessed turkey breast meat

Salmonella enterica Agona (S. Agona) and Salmonella enterica Saintpaul (S. Saintpaul) are among the emerging drug-resistant Salmonella in turkey production and processing. Rapid solutions to control emerging and uncommon serotypes such as S. Agona and S. Saintpaul are needed. This study tested pimenta essential oil (PEO) as a processing antibacterial against S. Agona and S. Saintpaul in experiments representative of different stages of turkey processing. The compound effectively reduced S. Agona and S. Saintpaul in nutrient broth studies and with mature biofilm assays. PEO was tested against a combination of S. Agona and S. Saintpaul in ground turkey meat and nonprocessed breast meat. In the first experiment with ground turkey, samples were inoculated with a mixture of S. Agona and S. Saintpaul (∼3 log10 CFU/g) and treated with PEO at different concentrations (0% PEO, 0.25% PEO, 0.5% PEO, 1% PEO, 2% PEO, and 2.5% PEO). In the second experiment with turkey breast, samples inoculated with ∼3 log10 CFU/g (SA+SP) were dipped in different concentrations of PEO with chitosan (CN) for 2 min. In both these experiments, samples were stored at 4°C, and Salmonella recovery was carried out at 0, 1, 3, 5, and 7 d. All experiments followed a completely randomized design and were repeated 6 times (n = 6). Statistical analysis was done using the PROC-ANOVA procedure of SAS. In the ground turkey meat, PEO at or above 2% reduced 2 log10 CFU/g of Salmonella by day 1. PEO at 2.5% in ground turkey meat resulted in enrichment-negative samples by 1 min, indicative of the rapid killing effect of the compound at a high concentration of PEO (P ≤ 0.05). A maximum reduction of 1.7 log10 CFU Salmonella/g of turkey breast meat was obtained after 2 min of dip treatment containing CN and 2.5% PEO. Results indicate that PEO could be used as a plant-based processing antibacterial against S. Agona and S. Saintpaul in turkey processing. Upscaling to plant-level studies is necessary before recommending its usage.

1436. Use of Whole Genome Sequencing to Characterize Antimicrobial-resistant Salmonella Berta Isolates from Clinical and Retail Meat Sources

BackgroundAntimicrobial resistance (AMR) in foodborne pathogens of animal origin, including non-typhoidal Salmonella (NTS) are a public health concern. Pennsylvania conducts integrated surveillance for AMR in NTS isolates from human and animal sources in collaboration with the National Antimicrobial Resistance Monitoring System (NARMS).MethodsDuring 2009-2014, Salmonella enterica isolates from various types of meat purchased from randomly selected retail outlets in southeastern Pennsylvania were analyzed by pulsed-field gel electrophoresis (PFGE). We compared PFGE patterns from meat with clinical isolates in the Pennsylvania surveillance database. All meat isolates and a subset of matched clinical isolates were tested for susceptibility to antimicrobial agents. Eleven isolates with indistinguishable PFGE patterns were analyzed by whole genome sequencing (WGS). Sequence data were uploaded to the FDA’s GalaxyTrakr platform for quality assessment, genome assembly, AMR gene detection, and phylogenetic inference via single-nucleotide polymorphism (SNP) analysis.ResultsPFGE patterns of 86 (48.6%) of 177 meat isolates had PFGE matches to 1,665 clinical isolates; 40 distinct PFGE patterns were represented among the shared patterns. Seventeen (43%) of the 40 shared PFGE patterns (with ≥1 isolate(s) from both sources) were considered multi-drug resistant (MDR). Among the 48 S. Berta pattern JAXX01.0001 isolates, 5 (10.9%) and 2 (100%) from human and meat sources respectively were MDR including resistance to amoxicillin and ceftriaxone. WGS analysis of one isolate from ground turkey meat (PNUSAS061602) was genetically related to clinical isolates including two within 9 and 11 SNPs [Figure]. Presence of genes that hydrolyze extended spectrum cephalosporins (ESC), [blaCMY, blaHERA, or blaTEM], was identified in eight (two meat and six clinical) isolates. One meat isolate was resistant to six antibiotics including ceftriaxone.Figure 2. Single nucleotide polymorphism (SNP) distance matrix showing relatedness in non-typhoidal Salmonella isolates from retail meat (n=2) and human (n=9) sources — Pennsylvania, 2010-2014. One S Berta from retail meat was separated from two clinical two clinical isolates by 9 and 11 SNPs. Second isolate from meat was separated from those associated with human infections by 14 (n=1), 17 (n=1) and ≥20 (n=7). ConclusionWGS analysis revealed clinically relevant ESCs genes in closely related S. Berta isolates from human and animal sources. Presence of these genes in NTS highlights the need for enhanced One-Health surveillance and judicious use of antibiotics in humans and food-animal production.Disclosures All Authors: No reported disclosures

Ultrasensitive and Rapid-Response Sensor for the Electrochemical Detection of Antibiotic Residues within Meat Samples.

Antimicrobial use in livestock has emerged as a pressing global issue because of the rise of antimicrobial-resistant bacteria. Regulatory authorities across the globe have taken steps to discourage the misuse of these antibiotics by banning or limiting the use of medically important antibiotics in food animals. However, to ensure that food animals are not being administered antibiotics inappropriately, there is a need for a reliable, raid-response biosensor that can detect the presence of these antibiotic residuals in meat products. We have developed an affinity-based electrochemical biosensor for the label-free detection of ceftiofur residues in meat samples. The sensor uses a self-assembled immunoassay to target the ceftiofur biomarker by employing electrochemical impedance spectroscopy to probe the interfacial capacitive changes as ceftiofur binds to the sensor surface. We have demonstrated a platform that can detect ceftiofur within 15 min of introducing the sample at concentrations down to 0.01 ng/mL in 1× phosphate-buffered saline and 10 ng/mL in 220 mg ground turkey meat samples.

Biopreservative Efficacy of Bacteriocin BacFL31 in Raw Ground Turkey Meat in terms of Microbiological, Physicochemical, and Sensory Qualities.

The effect of the semi purified bacteriocin BacFL31 at 200 and 400 AU/g on the shelf life of refrigerated raw ground turkey meat was investigated. The microbiological, physicochemical, and sensory properties of the meat samples were examined during refrigerated storage. The findings indicated that BacFL31 treatments were effective (p<0.05) against the proliferation of various spoilage microorganisms and suppressed the growth of Listeria monocytogenes and Salmonella Typhimurium. The pH, % Met-MB, and TBA-RS values of the treated samples were lower (p<0.05) than those of their control samples. The addition of BacFL31 extended the shelf life and enhanced the sensory attributes of the turkey meat samples during refrigerated storage. These results suggest that BacFL31 could be considered a promising candidate for future application as an additive to preserve the raw turkey meat during storage at 4℃.

Peach skin powder inhibits oxidation in cooked turkey meat

The objective of this study was to measure the antioxidant activity of peach skin and test the antioxidant effect of peach skin powder on cooked ground turkey meat during 12 d of refrigerated storage. Antioxidant activity of 3 cultivars of peaches grown in South Carolina was first evaluated by 3 antioxidant assays. The peach variety O'Henry showed the greatest antioxidant effect and therefore was used for further study. Two levels of peach skin powder (0.5%, 1%) and 0.01% butylated hydroxylanisole (BHA) were applied to ground turkey meat. Oxidation of cooked turkey meat was measured by detection of hexanal using gas chromatography-mass spectrometry. Results indicated that all levels of peach skin powder used in this study had an antioxidant effect on ground turkey with a greater effect at the higher concentration. O'Henry peach skin powder was as effective as BHA in preventing oxidation at the levels tested.

Survival after Cryogenic Freezing of Campylobacter Species in Ground Turkey Patties Treated with Polyphosphates

The use of polyphosphate-based marinades in the processing of poultry has been previously shown to increase the survival of Campylobacter species present in the exudates derived from these products. This study investigates the effects that some of the same polyphosphates have on the survival of Campylobacter species within a ground turkey product subjected to cryogenic freezing. Ground turkey patties with two different polyphosphate formulations added in two different concentrations were artificially contaminated with known concentrations of Campylobacter jejuni or Campylobacter coli. The patties were cryogenically frozen at —80°F (–62.2°C) with liquid nitrogen vapor and held at —20°C for 7 or 33 days, after which the number of Campylobacter surviving in the patties was determined. On average the cryogenic freezing resulted in a 2.5-log decrease in the survival of C. jejuni cells and a 2.9-log decrease in C. coli cells present in the turkey patties. Additionally, the presence of polyphosphates in the turkey patties had no effect on Campylobacter survival up to the maximum allowed concentration (0.5%) for polyphosphates in poultry marinades. Finally, it was determined that the added polyphosphates had little effect on the pH of the ground turkey meat; an effect which previously had been implicated in the enhancement of Campylobacter survival due to the presence of polyphosphates.

Rapid and Simultaneous Detection of Salmonella and Campylobacter in Poultry Samples Using Quantum Dots Based Fluorescent Immunoassay Coupled with Magnetic Immunoseparation

Salmonella Typhimurium and Campylobacter jejuni are the most important bacterial pathogens associated with food borne diseases caused by consuming undercooked poultry or handling raw poultry and poultry products. Because of their low infectious dose of pathogens, a rapid, sensitive, simultaneous detection method is urgently needed. The objective of our research was to develop a sensitive biosensing method for rapid and simultaneous detection of S. Typhimurium and C. jejuni in chicken and ground turkey meat using magnetic nanobeads (MNBs) to capture and separate the target bacteria and quantum dots (QDs) to label the captured bacteria. In this research, both streptavidin conjugated QDs 530 and QDs 620 were coated with the specific biotin conjugated anti-S. Typhimurium and anti-C. jejuni antibodies, respectively. The MNBs were separately coated with the specific biotin conjugated anti-S. Typhimurium and anti-C. jejuni antibodies. The inoculated poultry samples were mixed with conjugated MNBs to capture the two target bacteria. After magnetic immunoseparation, the MNB-cell complexes were mixed with the conjugated QDs 530 and QDs 620 to form the MNB-cell-QD complexes. Unattached conjugated QDs were removed using magnetic separation. Finally, the fluorescence intensities of the MNB-S. Typhimurium-QD and MNB-C. jejuni-QD complexes were measured and correlated to the cell number of two target pathogens. The results showed that S. Typhimurium and C. jejuni in pure culture, chicken carcass and ground turkey wash solutions could be simultaneously separated and detected using the developed immunoassay. The fluorescence intensities at 530 and 620 nm wavelengths increased linearly with the increasing cell numbers of S. Typhimurium and C. jejuni, respectively. The assay detection limit was 30-50 cfu/ml and the assay time was less than 2 h.

Pulsed-field gel electrophoresis pattern similarities between Listeria monocytogenes isolated from human patients and poultry in Chile

Listeria monocytogenes is the causal agent of listeriosis, a highly lethal food-borne disease. We identified isolates of L.monocytogenes present in poultry products bought at local retailers. The bacterial DNA was isolated and patterns were compared by pulsed-field gel electrophoresis (PFGE). Food isolates were also compared against three strains isolated from patients with listeriosis. Results showed 13 PFGE groups (>90% similarity). Of these, two patterns were shared by poultry and human strains. A particular group was found in 53% of the ground turkey meat and in a strain from a sporadic listeriosis case. Another group included an outbreak clone and 11 strains isolated from chicken. Data suggest L. monocytogenes should be included in risk assessment studies and hazard analysis and critical control point (HACCP) plans of this matrix. It is also important to reinforce consumer education to avoid health risks during handling and processing of these products.

Automated Extraction and Analysis of Salmonella enterica From Ground Turkey and Kitchen Surfaces

Salmonella enterica is a gram negative bacterium commonly associated with raw poultry and food borne illness. Evogen has developed a fully Automated Sample Preparation (ASP) instrument which was used to extract and purify DNA from ground turkey meat cultures and kitchen surface swabs. DNA purified on the ASP was then amplified using loop‐mediated isothermal amplification (LAMP). Five gram samples of fresh ground turkey were placed in 50 mL of culture media in sterile culture flasks, inoculated with S. enterica at 3800 cfu/mL and placed in a 37°C incubator for 24 hours. Kitchen surfaces which had been in contact with the fresh turkey were inoculated at 3800 cfu/mL and allowed to dry for 30 minutes. Swabs were used to sample surfaces and placed in 1 mL of culture media and cultured at 37°C for 24 hours. Following incubation, a 200 μl aliquot from each sample was placed in an ASP cartridge for DNA extraction and purification. DNA concentration was measured after extraction. 5.0μl of extracted DNA was then used for LAMP. The LAMP reactions were held at 65ºC for 30 minutes and an annealing curve was performed at 98–75ºC. All culture and swab samples extracted on the ASP provided positive results via LAMP within 12 minutes. The mean concentration of DNA recovered from the samples was 21.0 ng/μl ± 2.8 ng/μl. This new sample preparation system provides high quality DNA that was rapidly detectable by LAMP.Private Funding

Incidence and antibiotic resistance of Salmonella spp. in ground turkey meat

1. The objectives of this study were to isolate Salmonella spp. by conventional culture technique from ground turkey samples, to determine the seasonal distribution of Salmonella spp., to verify the isolates by PCR using primers based on oriC gene sequence, and to determine the antibiotic susceptibility profiles of the isolates. A total of 240 packaged fresh ground turkey samples marketed in Ankara were analysed between July 2004 and June 2005. 2. One hundred and ten out of 240 (45⋅8%) samples were positive for Salmonella spp. and confirmed by PCR. The distribution of Salmonella spp. was determined as 48⋅3, 55⋅0, 63⋅3 and 16⋅6%, during spring, summer, autumn and winter, respectively. Statistical analysis showed a significant difference for the prevalence of Salmonella spp. between winter and the other seasons. 3. Of the isolates, 54 out of 110 (49⋅0%) were resistant to one or more antibiotics tested. The highest resistance was observed to nalidixic acid (25⋅4%), followed by streptomycin (17⋅2%) and tetracycline (15⋅4%). 4. In conclusion, this is a disturbing finding, both for the high prevalence of Salmonella and the extent of antibiotic resistance. Ground turkey should be produced under suitable hygienic and technological conditions and the use of antimicrobials must be controlled by governmental agencies to protect public health from salmonellosis and from the consequences of increased resistance to the antibiotics.

Study on the microbial status of unseasoned ground turkey meat from an EU producer–a new product with risk potential?

1. The aim of this study was to point out potential risks associated with a product new to the market in the European Union: unseasoned minced turkey meat. 2. On 6 d of sampling, minced turkey meat from a large-scale EU producer was analysed at 4 processing stages. 3. The packaged minced meat was examined during 10 d of storage, once using the legally recommended conditions (<+2°C), and then under simulated consumer handling; one batch was stored for 3 d at +2°C then kept for 45 min at 25°C and then stored at +7°C. Microbiological and physical variables were tested on 5 d. 4. Results showed that the mean total aerobic plate count (APC) of the unprocessed material was 3.8 log CfU/g and did not rise significantly, although the temperature rose briefly after the material left the meat chopper. Listeria monocytogenes was the pathogen detected most often, in 7 (14.6%) of 48 samples, followed by Salmonella in one (2.1%). No Campylobacter were found. 5. Initial contamination (APC) of about 4.5 log CfU/g was common in stored minced meat, conforming to European Union Regulations EC 2073/2005 and 1441/2007. Brochothrix thermosphacta and Pseudomonas spp. were the bacteria found most frequently. Under strict maintenance at a storage temperature of +2°C, the maximum microbiological stability of the material was 7 d. Under simulated consumer handling, the microbial counts increased significantly, immediately after transport. 6. Our findings indicate that unseasoned minced turkey meat is a risky, perishable product, especially if the raw material does not have a low APC, is not pathogen-free and is kept under typical consumer handling and storage conditions.

Preliminary study for evaluation of avian influenza virus inactivation in contaminated poultry products using electron beam irradiation

Spread of avian influenza is associated with movement of infected poultry and poultry products, and, as a result, strict international trade restrictions are in place. In addition, the possibility of transmission of avian influenza virus (AIV) strains to mammalian species by the consumption or handling of infected poultry, although a rare occurrence, is an important trade concern. Traditional methods for poultry product decontamination, such as thermal processing, are effective in inactivating AIV. However, alternative technologies such as electron beam (E-beam) irradiation offer some advantages in maintaining organoleptic properties of fresh poultry products. This study was designed to evaluate the applicability of high-energy (10 MeV) E-beam irradiation to inactivate AIV and reduce virus loads in egg products and poultry meat. Commercially available egg-white and ground turkey meat samples were spiked with the low-pathogenic A/chicken/TX/2002 H5N3 AIV and exposed to varying doses of high-energy E-beam irradiation in increments ranging from 0 kGy to 8 kGy. The viral titres in irradiated samples showed a linear dose-dependent reduction. The dose required to achieve 90% reduction (i.e. the D 10 value) of viable AIV loads was 2.3 kGy in phosphate buffer, 1.6 kGy in egg-white and 2.6 kGy in ground turkey meat samples. The effectiveness of E-beam irradiation to inactivate AIV was similar to the previously reported effectiveness of the E-beam against poliovirus and rotavirus. These results illustrate the potential applicability of high-energy (10 MeV) E-beam irradiation as a poultry product decontamination technology to inactivate AIV.

U.S. Food Safety and Inspection Service Testing for Salmonella in Selected Raw Meat and Poultry Products in the United States, 1998 through 2003: An Establishment-Level Analysis

The U.S. Food Safety and Inspection Service (FSIS) pathogen reduction–hazard analysis critical control point systems final rule, published in 1996, established Salmonella performance standards for broiler chicken, cow and bull, market hog, and steer and heifer carcasses and for ground beef, chicken, and turkey meat. In 1998, the FSIS began testing to verify that establishments are meeting performance standards. Samples are collected in sets in which the number of samples is defined but varies according to product class. A sample set fails when the number of positive Salmonella samples exceeds the maximum number of positive samples allowed under the performance standard. Salmonella sample sets collected at 1,584 establishments from 1998 through 2003 were examined to identify factors associated with failure of one or more sets. Overall, 1,282 (80.9%) of establishments never had failed sets. In establishments that did experience set failure(s), generally the failed sets were collected early in the establishment testing history, with the exception of broiler establishments where failure(s) occurred both early and late in the course of testing. Small establishments were more likely to have experienced a set failure than were large or very small establishments, and broiler establishments were more likely to have failed than were ground beef, market hog, or steer-heifer establishments. Agency response to failed Salmonella sample sets in the form of in-depth verification reviews and related establishment-initiated corrective actions have likely contributed to declines in the number of establishments that failed sets. A focus on food safety measures in small establishments and broiler processing establishments should further reduce the number of sample sets that fail to meet the Salmonella performance standard.

Growth Depth Effects of Bacteria in Ground Turkey Meat Patties Subjected to High Carbon Dioxide or High Oxygen Atmospheres

Modified atmosphere packaging (MAP) is used to extend the shelf life of ground meats by altering the gas atmosphere surrounding the meat. This study evaluated how deep MAP bactericidal effects penetrate into a ground meat patty. Patties made from freshly ground turkey breasts were subjected to 2 MAP treatments of high CO(2) (97%) or high O(2) (80% O(2), 20% CO(2)). Total plate and lactic acid bacterial counts were determined for 3 patty depths (top, middle, bottom). Meat surface color and the package gas headspace composition were also measured. All analyses were performed on 0, 3, 6, 9, and 12 d. Changes in gas headspace and meat surface color were also measured at 0, 3, 6, 9, and 12 d. High CO(2) atmosphere maintained a better meat surface color than high O(2) atmosphere over the whole storage period. Overall counts were lower (P < or = 0.05) in a high-CO(2) atmosphere compared with a high-O(2) modified atmosphere. Patties stored under a high-CO(2) atmosphere displayed slower bacterial growth in the top layer compared with the middle and bottom layers. Total plate count did not differ (P > or = 0.05) in layers for patties pack-aged in a high-O(2) atmosphere Lactic acid bacterial counts increased in the high-O(2) modified atmosphere by d 9 and 12 of storage; no increase was observed in CO(2)-packaged patties. Thus, high-CO(2) MAP slowed the growth of total bacteria as well as lactic acid bacteria. Also, there was slower growth in the top meat layer exposed to CO(2) compared with interior layers.

Influence of Dietary Vitamin E on Behavior of Listeria monocytogenes and Color Stability in Ground Turkey Meat following Electron Beam Irradiation

There is growing concern that the free radical scavenging effect of antioxidants added to meats might reduce the antimicrobial effectiveness of ionizing radiation. A study was conducted to determine the effect of vitamin E on the behavior (growth) of Listeria monocytogenes and color stability in turkey meat following electron beam irradiation. Raw ground turkey breast meat from birds fed diets containing 0 (control), 50, 100, and 200 IU/kg of vitamin E was inoculated with a five-strain mixture of L. monocytogenes to give approximately 107 CFU/g. Inoculated samples were irradiated at 0, 0.5, 1, and 2 kGy and stored aerobically (12 days) or under vacuum (42 days) at 4°C. L. monocytogenes survivors were determined by plating samples on modified Oxford medium and counting colonies on modified Oxford medium plates after 48 h at 35°C. Meat color was measured using a colorimeter. Irradiation at 2.0 kGy resulted in an approximately 3.5-log reduction of initial numbers of L. monocytogenes. There were no significant differences in D-values (decimal reduction times) for L. monocytogenes in meat irrespective of vitamin E treatment (P > 0.05). Also, vitamin E treatments did not affect growth of the pathogen in aerobic or vacuum-packaged samples following irradiation (P > 0.05). Compared with controls, irradiated meat from birds fed 100 or 200 IU/kg of vitamin E demonstrated significant improvement in color stability (lightness and redness values) during aerobic storage (P < 0.05). Dietary vitamin E (100 to 200 IU/kg) has good potential for improving the color stability of turkey meat without compromising the microbial safety of the irradiated product.

Shelf life of ground poultry meat stored under modified atmosphere

The shelf life of ground chicken and turkey meat packaged under a modified atmosphere containing O2 and a high level of CO2 (62% CO2, 8% O2, and 30% N2; gas-1), or a gas mixture without O2 (20% CO2 and 80% N2; gas-2) was evaluated for 20 d at 1 C. Meat packaged under gas-2 maintained a higher a* value (redness) throughout the experiment and generally had a more appealing color than the meat packaged using gas-1. Microbial populations were assessed after 8, 12, and 15 d of storage. Total aerobic mesophilic counts were higher in chicken meat than in turkey throughout storage. Coliforms and Escherichia coli counts were lower in meat packaged under gas-1. After 15 d of storage at 1 C, Brochothrix thermosphacta was detected only in ground chicken meat packaged using gas-2. Meat packaged under the gas mixtures tested had similar counts for presumptive pseudomonads, Staphylococcus aureus, and lactic acid bacteria. These results indicate that an appropriate gas mixture can maintain a desirable color in ground poultry meat but offers no guarantees with respect to the microbial profile of meat.

Effect of dry honey on oxidation in turkey breast meat

The effect of adding dry honey to turkey breast meat on oxidative stability was measured using TBA, volatile headspace, and oxidative stability index. Ground turkey breast meat was mixed with different concentrations of dry honey (0, 1, 5, 10, 15, and 20%) then cooked in polyethylene bags to 72 C. Oxidative stability measurements were taken for raw meat and cooked meat and for cooked meat after 48 h of storage at 4 C. The proximate composition of the raw meat was 73.9% moisture, 23.2% protein, and 1.3% fat. Gas headspace analysis determined hexanal to be the most abundant volatile compound. Hexanal content decreased as the amount of added honey increased in both freshly cooked meat and in meat stored for 48 h at 4 C. The TBA values also decreased with increasing levels of added honey in the freshly cooked and 48-h-stored meats. The percentage inhibition of oxidation for the 5, 10, 15, and 20% samples increased from 50 to 76% for the freshly cooked meat and from 34 to 88% for the 48-h-stored meat. The oxidative stability index increased with increasing concentrations of honey from 0.28 h (control) to 7.73 h (20% honey). Addition of up to 15% honey inhibited the development of oxidative compounds in cooked turkey meat, with little further inhibition observed compared to 20% honey.