Fresh Poultry Products Research Articles

Quantitative microbiological spoilage risk assessment (QMSRA) of fresh poultry fillets during storage at retail

A quantitative microbiological spoilage risk assessment model (QMSRA) of aerobically stored fresh poultry fillets was developed based on pseudomonads growth and metabolic activity. Simultaneous microbiological and sensory analyses were performed in poultry fillets to evaluate the relation between pseudomonads concentration and sensory rejection due to spoilage. The analysis showed no organoleptic rejection at pseudomonads concentrations less than 6.08 log CFU/cm2. For higher concentrations, a “spoilage-response” relationship was developed using a beta-Poisson model. The above relationship was combined with a stochastic modeling approach for pseudomonads growth by taking into account both variability and uncertainty of factors affecting spoilage. To enhance the reliability of the developed QMSRA model, uncertainty was quantified and separated from variability using a second order Monte Carlo simulation. For a batch of 10,000 units, the QMSRA model predicted a median number of 11, 80, 295, 733 and 1,389 spoiled units for retail storage times of 6,7, 8, 9 and 10 days, respectively, while no spoiled units were predicted for storage time of up to 5 days at retail. Scenario analysis showed that a reduction of 1 log in the pseudomonads concentration at the time of packaging or 1 °C in retail storage temperature results in up to 90% reduction of the spoiled units while the combination of the above interventions can reduce the risk of spoilage by up to 99%, depending on the storage time. The poultry industry can utilize the QMSRA model as a transparent scientific basis to support food quality management decisions in determining appropriate expiration dates which maximize the utilization of the product’s “true” shelf life while minimize the risk of spoilage to an acceptable level. Furthermore, the scenario analysis can provide the necessary components for an effective cost-benefit analysis, enabling the identification and comparison of appropriate strategies for extending the shelf life of fresh poultry products.

Development and validation of a mathematical model for pseudomonads growth as a basis for predicting spoilage of fresh poultry breast and thigh fillets

The growth of naturally contaminated pseudomonads on fresh breast and thigh poultry fillets during aerobic storage was studied and modeled as a function of temperature (0–30°C). A statistical comparison of the models for breast and thigh fillets showed that muscle type does not significantly affect the temperature dependence of pseudomonads growth kinetics. A unified model for breast and thigh was developed and validated against pseudomonads growth rate data under isothermal conditions extracted from literature and experimental data under dynamic temperature conditions. The validation results showed a satisfactory performance of the model with the bias and accuracy factors ranging from 0.85 to 1.09 and 1.02 to 1.21, respectively. The model was further used to predict the shelf life of fresh poultry as the time required by pseudomonads to reach the spoilage level for various scenarios of temperature, initial contamination level, and physiological state of pseudomonads demonstrating its application in a risk-based shelf-life assessment of fresh poultry products.

Functional edible films/coatings integrated with lactoperoxidase and lysozyme and their application in food preservation

Concerning environmental pollution caused by plastic-based food packaging materials and the demand for healthy and safe food, the development of edible food packaging films/coatings with antimicrobial properties is urgently required. Lactoperoxidase (LP) and lysozyme (LY), biopreservation enzymes commonly used in the food industry, appear to be excellent choices for incorporating edible films/coatings to improve food preservation capabilities. In this review, the results of recently published studies on the functional properties and applications of edible films/coatings containing LP and LY are comprehensively reviewed. Several commonly used biomacromolecules have been discussed, such as chitosan, alginate, whey protein, and gelatin, used to prepare edible films/coatings integrated with LP and LY. The application of biopolymer-based films/coatings containing LP and LY to various food packaging was also discussed. Because LP and LY are safe, stable, and have strong antimicrobial properties, and are compatible with most biological macromolecules, the edible films/coatings integrated with LP and LY are suitable for preserving various foods such as fresh fruit, poultry, and seafood products. In addition, the use of edible films/coatings integrated with LY and LP in combination with other food preservation methods or antioxidants in food preservation applications is expected to have the more significant positive effect than single addition.

Evaluation of Antimicrobial Coatings on Preservation and Shelf Life of Fresh Chicken Breast Fillets Under Cold Storage.

Fresh poultry products such as chicken breast are very convenient for consumption due to their availability and nutritional and sensory characteristics but they have a short shelf life (3–5 days) due to their high water activity and propensity to microbial contamination and spoilage. In this work, the characteristics of edible coatings (EC) prepared from various formulations of guar gum (GG) and isolated soy protein were evaluated. From this evaluation, and due to the guar gum EC being the most suitable, antimicrobial coatings were prepared with different proportions of GG, nisin, and oregano oil to determine its effect on shelf life and change in physicochemical and microbiological properties of chicken breast fillets under refrigerated conditions. Fresh samples were coated with a coating-forming solution based on GG and stored at 4 °C for 16 days. During this time, the change in color, firmness, acidity, pH, growth of microorganisms was determined, and sensory tests of appearance, taste, and odor were performed. GG-coated samples retained color and firmness during storage. Likewise, a decrease in weight loss was achieved in the treated samples, and the sensory attributes were preserved compared to the uncoated samples. The application of the coating considerably delayed the growth of microorganisms, increasing the product shelf life (9 days) compared to the control samples (6 days).

Spoilage of fresh turkey and pork sausages: Influence of potassium lactate and modified atmosphere packaging

Fresh poultry and pork meat products represent highly perishable products which are susceptible to spoil within a few days after production. Lactate addition and modified atmosphere packaging are common preservation strategies used to overcome spoilage. This study aimed to identify the effects of these strategies and their possible interactions on spoilage indicators simultaneously on fresh pork and turkey sausages. Ten batches of raw meat (turkey or pork) sausages were industrially produced with different lactate concentrations (0, 1 or 2% w/w in turkey and 0, 0.57 and 1.13% w/w in pork), packed under different gas mixtures (air, MAP1: 70% O2 – 30% CO2 and MAP2: 50% CO2 − 50% N2) and chill stored during 22 days. Spoilage responses including enumeration of total aerobic mesophilic and lactic acid bacteria, measurement of pH and colour, evaluation of visual defects and off-odour, were monitored. Effects of lactate and modified atmosphere packaging (MAP) as well as random effect of the batch variability were studied using a mixed effect model. Despite initial batch variability, significant effects of lactate and gas packaging were observed but in a different way in turkey and pork. Our results suggest that for fresh turkey sausages, the gas mixture enriched in oxygen enhanced off-odour perception and sausage discolouration from red to dark grey / brown colour. Unlike turkey sausages, in pork sausages, lactate did not significantly influence the monitored spoilage responses, whereas MAP (70% O2-30% CO2) reduced the off-odour perception. The developed model could be useful to estimate the effect of preservation strategies on spoilage occurrence while considering industrial batch variability.

Analysis of Benzalkonium Chloride Resistance and Potential Virulence of Listeria monocytogenes Isolates Obtained from Different Stages of a Poultry Production Chain in Spain

Listeria monocytogenes can survive in food production facilities and can be transmitted via contamination of food during the various stages of food production. This study was conducted to compile the results of three independent previous studies on the genetic diversity of L. monocytogenes in a poultry production company in Spain and to determine the potential virulence and sanitizer resistance of the strains by using both genotype and phenotype analyses. L. monocytogenes was detected at three production stages: a broiler abattoir, a processing plant, and retail stores marketing fresh poultry products from the same company. These three stages spanned three locations in three provinces of Spain. A set of 347 L. monocytogenes isolates representing 39 subtypes was obtained using pulsed-field gel electrophoresis (PFGE). A total of 28 subtypes (68%) had a full-length internalin A gene, and two subtypes had a phenotype with low potential for virulence because of a mutation in the prfA gene. A total of 32 subtypes (82%) were classified as benzalkonium chloride resistant (BAC-R) and contained the resistance determinant bcrABC (21 subtypes, 54%) or the resistance gene qacH (11 subtypes, 28%). A total of 13 persistent BAC-R subtypes (minimum of 3 months between the first and last sample from with the isolate was recovered) were identified at the abattoir and processing plant. The three production stages shared a unique subtype (PFGE type 1), which had the mutation in the prfA gene and the bcrABC resistance determinant. Whole genome sequencing revealed this subtype to be sequence type 31. Limited genetic diversity was noted in the isolates studied, including some subtypes that were persistent in the environment of the investigated facilities. Given the high prevalence of BAC-R subtypes, these results support the association between resistance to biocides and persistence of L. monocytogenes.

Growth and Persistence of Campylobacter jejuni in Foodstuffs.

Campylobacter genus bacteria causing campylobacteriasis are difficult to culture. This fact necessitates creation of special approaches to studies of the behavior of these pathogens during the manufacture and storage of foodstuffs. The regularities of Campylobacter jejuni transition into an uncultivable state are studied under conditions simulating the process of immersion cooling of fresh poultry products. The proportion of viable colony-forming (CFU) cells to the total count of planktonic and uncultivable cells in the population was calculated by the level of genomic DNA in the samples evaluated by quantitative real-time PCR with intercalating dyes. PCR was carried out with primers detecting the cytolethal toxin subunit B gene cdtB and invasion gene ciaB in C. jejuni strains. The count of detected cells was 5-10-fold higher than the count of CFU; the cultural method failed to detect the agent in 40% analyzed samples of superficially infected products, while the level of uncultivable cells detected by PCR was significantly higher. The relationship between culturing conditions and formation of C. jejuni biofilms was studied. The most intensive formation of film exomatrix was observed under unfavorable conditions for this microorganism at 25oC. In microaerophilic gaseous medium, weak formation of films and intensive growth of C. jejuni populations were observed. Culturing at higher temperatures (37-42oC) was in fact inessential for the film formation process.

Prevalence, phenotypic and genetic diversity of Campylobacter in poultry fresh meat and poultry products on retail sale in Tuscany (Italy).

In this study, the prevalence of Campylobacter spp. in poultry fresh meat and ready‑to‑cook products was evaluated. Seventy‑three samples were collected at retail level from supermarkets and discount stores, obtaining 61.6% positivity. Of 133 Campylobacter isolates, 86 strains (Campylobacter coli, 58.1% and Campylobacter jejuni, 41.9%) were selected for characterisation on the basis of their SmaI and kpnI pulsed field gel‑electrophoresis (PFGE) profiles, to exclude clonal replicates. Campylobacters resulted highly resistant to tetracycline, ciprofloxacin, and nalidixic acid (79.1%, 72.1% and 65.1%, respectively); 50% of C. coli and 13.9% of C. jejuni were resistant to ciprofloxacin and erythromycin, the most important antimicrobials for human campylobacteriosis therapy. Five C. coli were resistant to 5/7 of the tested antimicrobials. HS4c was the prevailing C. jejuni serotype group (22.3%), whereas 8 other serotypes were identified in low percentages. SmaI and kpnI profiles showed a wide variability. The survey showed a high Campylobacter contamination of poultry meat and poultry products at retail level in Tuscany, Italy. A wide strains' heterogeneity and a remarkable level of strains' antimicrobial resistance have been reported, confirming the need for an improvement of specific preventive measures along the production chain.

Use of Vinegar and Jasmine Tea Extract to Control Foodborne Pathogens and Spoilage Micro-Organisms in Fresh Chicken Sausage

ObjectivesConsumer demand for natural preservatives is on rise. Verdad Avanta F100 is a natural vinegar blended with jasmine tea extract (VJTE) and has excellent antimicrobial and antioxidant properties. Salmonella can be a serious problem in fresh poultry products such as fresh chicken sausage. Under abusive temperature storage conditions, Salmonella can grow in poultry products. Aerobic plate counts (APC), Psychrotrophic, Enterobacteriacae and Lactic acid bacteria (LAB) counts are reported to determine the shelf life of the fresh chicken sausage. This study evaluates the impact of vinegar and jasmine tea extract on the shelf life of fresh ground chicken sausage. The objective is to validate the efficacy of vinegar and jasmine tea extract for Salmonella control and shelf-life extension of fresh ground chicken sausage. Materials and MethodsFresh bone-in, skin-on chicken thighs were deboned and ground to 4 mm and mixed with additional ingredients (water, salt, garlic powder, black pepper, onion powder, mustard powder) for control, and 2 levels of VJTE (0.70% and 1.00%). A 5 strain cocktail of Salmonella spp. was used in this study; including: Salmonella enterica; subsp. enterica; serovar Enteritidis, Salmonella enterica; subsp. Enterica; serovar Enteritidis, Salmonella enterica; subsp. Enterica; serovar Typhimurium, Salmonella enterica; subsp. Enterica; serovar Typhimurium and Salmonella enterica; subsp. Enterica; serovar Heidelberg. For inoculated chicken samples approximately 1,000 g of mixed sausage was placed in a plastic bag along with 1 mL of 4.5 log CFU/mL of Salmonella cocktail and mixed together to achieve a final count of 2.5 log CFU/g of Salmonella in the sausage. Inoculated samples were stored at 4 and 15.4°C for 27 and 13 d, respectively. Non inoculated samples were stored at 4°C for 27 d. pH, moisture, water activity were measured for all treatments. The plating for each microflora was done independently- in duplicate and at approximately 0, 7, 11, 20, and 27 d for the non-inoculated samples and at approximately 0, 5, 8, 13 d for the Salmonella inoculated samples. ResultsSalmonella has been shown not to grow under refrigerated temperatures and our results show no growth for any samples over 13 d during refrigerated storage. Salmonella growth indicates that even under temperature abused conditions (15.4°C) vinegar and jasmine tea extract were able to limit the growth of Salmonella for 13 d whereas the control reached 6.54 log CFU/g in 5 d. APC growth kinetics indicate vinegar and jasmine tea extract extended the shelf life of chicken sausage for the full 27 d whereas the control showed 7.00 log CFU/g increase at 11 d. Enterobacteriaceae growth data indicates that use of vinegar and jasmine tea extract inhibited the outgrowth over the shelf life to the initial level, while the control treatment had 7.08 log CFU/g increase in 14 d. ConclusionThis research validates the antimicrobial efficacy of Vinegar and jasmine tea extract (VJTE) in chicken sausage to control the growth of Salmonella under abused temperature conditions and to extend the shelf-life of fresh chicken sausage and provides the meat industry with a highly effective natural antimicrobial to assure the food safety as well the shelf life of the product.

Effect of supply of fresh poultry products on reducing environment contamination of avian influenza virus in markets

To evaluate the effect of supply of fresh poultry products on reducing environment contamination of avian influenza virus (AIV) in markets in Guangzhou. A total of 40 markets, including 20 selling alive poultry and 20 selling fresh poultry products, were selected randomly in Guangzhou to conduct environment surveillance in 80 poultry stalls every 4 months from July 2014 to April 2015. Four smear samples were collected from different sites of each poultry stall to detect nucleic acid of AIV. The positive samples were further detected for AIV subtype H5, H7 and H9 nucleic acids. Among 40 alive poultry stalls, 95.0% (38/40) kept alive poultry overnight, 25.0% (10/40) were disinfected daily, 95.0% (38/40) were cleaned up weekly, 95.0% (38/40) were closed for one day every month. Among 40 fresh poultry product stalls, 20.0% (8/40) were disinfected daily, 90.0% (36/40) were cleaned up weekly, and 96.0% (38/40) ever sold dressed poultry from alive poultry markets. The positive rate of AIV in alive poultry markets was 40.4% (252/623), higher than that in fresh poultry product markets (32.3%, 197/610), the difference was significant (χ(2)=8.85, P=0.003), and the positive rate of subtype H9 virus in alive poultry markets was 28.6% (178/623), higher than that in fresh poultry product markets (16.2%, 99/610), the difference was significant (χ(2)=26.95, P<0.001). In fresh poultry product markets, the positive rate of AIV in stalls selling dressed poultry was 37.3% (180/482), higher than that in stalls selling no dressed poultry (13.3%, 17/128), the difference was significant (χ(2)=26.78, P<0.001), and the positive rate of subtype H9 virus in stalls selling dressed poultry was 19.1% (92/482), higher than that in stalls selling no dressed poultry (5.5%, 7/128), the difference was significant (χ(2)=13.80, P<0.001). Both the positive rate of AIV and the positive rate of subtype H9 virus were highest in the second round surveillance (October 2014). The differences in AIV and its subtype H5, H7 and H9 virus positive rates of environmental samples from four different sites were not significant, respectively. In the same sample site, the positive rate of subtype H9 virus in alive poultry markets was higher than that in fresh poultry product markets the difference was significant (P<0.05). The supply of fresh poultry products could effectively reduce the level of environment contamination of AIV in markets. Dressed poultry supplement caused the risk of AIV spread in fresh poultry product markets.

Combinations of plant-derived compounds against Campylobacter in vitro

Campylobacter occur in fresh retail poultry products as a result of their colonization of the gastro-intestinal tract of chickens during growth. Feed additives could be used for suppression of Campylobacter levels in the chickens prior to slaughter. To address this opportunity, feed manufacturers are targeting natural antimicrobials from plant material as new forms of consumer-accepted feed additives. However, to be practical, these natural antimicrobials must be effective at low concentrations. The current study has validated an improved laboratory method to study minimal inhibitory concentrations of plant compounds and their combinations against Campylobacter. The assay was shown to be valid for testing lipid-soluble and water-soluble plant extracts and byproducts from the food industry. The study screened 29 extracts or plant-derived compounds and their mixtures for anti-Campylobacter activity using a laboratory assay. Combinations of oregano, lactic acid, and sorghum byproduct showed effective synergy in anti-Campylobacter activity. The synergies allowed a large reduction in the concentration of the individual compounds needed to kill the bacteria with an 80% reduction in concentration being achieved for oregano essential oil. The assay gives rise to further opportunities for the testing of a greater range of combinations of plant-derived compounds and other natural antimicrobials. The method is robust, simple, and easily automated, and it could be used to adjust the cost of feed formulations by reducing costs associated with antimicrobial feed additives.

A Healthy Diet Is Associated with Less Endothelial Dysfunction and Less Low-Grade Inflammation over a 7-Year Period in Adults at Risk of Cardiovascular Disease1–3

Background: A healthy diet rich in fish, fruit, and vegetables, but moderate in alcohol and low in dairy products and meat, has been associated with a lower rate of incident cardiovascular disease (CVD). The underlying mechanisms, however, remain unclear. Endothelial dysfunction and low-grade inflammation play important roles in CVD. A healthy diet might modify these phenomena.Objective: We investigated the associations between the above food groups and overall biomarker scores of endothelial dysfunction and low-grade inflammation in a 7-y longitudinal study.Methods: Using longitudinal data from 557 participants at increased CVD risk from the CODAM (Cohort on Diabetes and Atherosclerosis Maastricht) Study, we assessed diet intake by food-frequency questionnaire and measured plasma biomarkers of endothelial dysfunction [von Willebrand factor, soluble vascular cell adhesion molecule 1, soluble endothelial selectin, soluble thrombomodulin, soluble intercellular adhesion molecule 1 (sICAM-1)] and low-grade inflammation [C-reactive protein, serum amyloid A, interleukin (IL)-6, IL-8, tumor necrosis factor α, and sICAM-1]. At baseline, participants were aged 59.6 ± 6.9 y. Measurements were performed then and after 7 y. Biomarkers were combined into overall scores (sum of z scores; higher scores indicating worse function). Longitudinal data were analyzed with generalized estimating equations and adjusted for sex, age, glucose metabolism, energy intake, body mass index, physical activity, alcohol consumption, and smoking.Results: Higher consumption of fish (per 100 g/wk), but not total consumption of vegetables, fruit, alcohol-containing beverages, dairy products, or meat, was associated with a lower overall endothelial dysfunction score over 7 y (β: −0.027; 95% CI: −0.051, −0.004). No associations were observed with the overall low-grade inflammation score. Further food component analyses indicated that consumption of more lean fish (per 100 g/wk) and raw vegetables (per 100 g/d), and fewer high-fat dairy products (per 100 g/d) was associated with less endothelial dysfunction [(β: −0.038; 95% CI: −0.072, −0.005), (β: −0.095; 95% CI: −0.191, 0.000), and (β: −0.070; 95% CI: −0.131, −0.009), respectively]. Consumption of more fresh fruit (per 100 g/d), wine (per 100 mL/wk), and poultry (per 100 g/d), and fewer high-fat dairy products (per 100 g/d) was associated with less low-grade inflammation [(β: −0.074; 95% CI: −0.133, −0.015), (β:−0.006; 95% CI: −0.013, 0.001), (β:−0.247; 95% CI: -0.479, -0.014), and (β:−0.100; 95% CI: −0.182, −0.019), respectively].Conclusion: These data suggest that the dietary modification of endothelial dysfunction and low-grade inflammation, processes that are important in atherothrombosis, is possible.

Development of a novel antimicrobial film based on chitosan with LAE (ethyl-Nα-dodecanoyl-l-arginate) and its application to fresh chicken

Chitosan (CS) films incorporating the antimicrobial compound ethyl-Nα-dodecanoyl-l-arginate (LAE) were developed for food packaging applications. Cast chitosan films were made with 1, 5 or 10% LAE and 20% glycerol in the film forming solution. Optical properties, release of LAE and antimicrobial activity of developed films was determined. The minimum inhibitory concentration (MIC) and the minimum biocide concentration (MBC) of LAE were determined. CS films with LAE were transparent and uniform, without discontinuities or visible particles and no visual differences could be perceived between CS and CS-LAE films. When in contact with an aqueous food simulant, the agent was fully released following a Fickian behavior in a few hours at 4 and 28°C. Antimicrobial activity of films against mesophiles, psychrophiles, Pseudomonas spp., colifoms, lactic acid bacteria, hydrogen sulfide-producing bacteria, yeast and fungi, was evaluated at two, six and eight days for its application on chicken breast fillets. Films were active against bacteria, yeasts and fungi in liquid and solid media. CS films evidenced antimicrobial activity in the range 0.47–2.96 log reductions, while CS-5%LAE film produced 1.78–5.81 log reduction. Results highlighted that LAE incorporation in a chitosan-based packaging structure may provide a relevant antimicrobial activity that could improve the stability of fresh poultry products.

Characterization of Methicillin-Resistant Staphylococcus aureus Isolates from Food and Food Products of Poultry Origin in Germany

During a survey of fresh chicken and turkey meat as well as chicken and turkey meat products for the presence of methicillin-resistant Staphylococcus aureus (MRSA) isolates in Germany, 32 (37.2%) of 86 samples were MRSA positive. Twenty-eight of these MRSA isolates belonged to clonal complex 398 (CC398), which is widespread among food-producing animals. These CC398 isolates carried SCCmec elements of type IV or V and exhibited spa type t011, t034, t899, t2346 or t6574 and either the known dru types dt2b, dt6j, dt10a, dt10q, dt11a, dt11v, and dt11ab or the novel dru types dt6m, dt10as, and dt10at. In addition, two MRSA sequence type 9 (ST9) isolates with a type IV SCCmec cassette, spa type t1430, and dru type dt10a as well as single MRSA ST5 and ST1791 isolates with a type III SCCmec cassette, spa type t002, and dru type dt9v were identified. All but two isolates were classified as multiresistant. A wide variety of resistance phenotypes and genotypes were detected. All isolates were negative for the major virulence factors, such as Panton-Valentine leukocidin, toxic shock syndrome toxin 1, or exfoliative toxins. In contrast to the MRSA CC398 isolates, the four ST9, ST5, or ST1791 isolates harbored the egc gene cluster for enterotoxin G, I, M, N, O, and U genes. Although the relevance of contamination of fresh poultry meat or poultry products with MRSA is currently unclear, the presence of multiresistant and, in part, enterotoxigenic MRSA emphasizes the need for further studies to elucidate possible health hazards for consumers.

A National Epidemic of Campylobacteriosis in Iceland, Lessons Learned

Epidemics often result in organizational, policy and technical changes within a country. In 1999, an epidemic of campylobacteriosis was reported in Iceland. The recent availability of fresh poultry products in the marketplace was suggested as the source of infection. This paper reports on the context of the epidemic, reviews interventions implemented to prevent campylobacteriosis, and discusses lessons learned. A retrospective study of interventions implemented in Iceland from June 1995 to December 2007 was conducted by interviewing key informants and reviewing Iceland's literature. Cumulative incidence rates of domestic campylobacteriosis by year and average incidence rates per epidemic period were calculated. Interventions included on-farm surveillance of Campylobacter, producer education, enhanced biosecurity measures, changes in poultry processing, a leak-proof packaging policy, a freezing policy for products from Campylobacter-positive poultry flocks, consumer education, and the creation of a legislated inter-organizational response committee. These interventions appear to have collectively contributed to a decrease in campylobacteriosis' incidence rate near pre-epidemic baseline levels. Expert consultations revealed that the implementation of a Campylobacter surveillance program in poultry and the freezing policy were critical to controlling the disease in the Icelandic population. It was also recognized that new multidisciplinary collaborations among public health, veterinary, and food safety authorities and a sustained co-operation from the poultry industry were integral factors to the mitigation of the epidemic. Iceland's response to the campylobacteriosis epidemic is a lesson learned of inter-disciplinary and inter-organizational precautionary public health action in the face of a complex public health issue.

The temporal, PFGE and resistance pattern associations suggest that poultry products are only a minor source of human infections in Western Finland

In order to compare human and retail poultry meat thermophilic Campylobacter isolates originating in a regional area in Western Finland, minimum inhibitory concentration (MICs) for six antimicrobials (96 isolates) and pulsed-field gel electrophoresis (PFGE) (102 isolates) were analysed. Campylobacter spp. were detected in 10.5% out of 305 fresh poultry products studied; 29 (90.5%) isolates were identified as Campylobacter jejuni. Among the 70 human isolates, 66 (94.3%) isolates were identified as C. jejuni. Only one C. jejuni domestic poultry isolate showed resistance (ampicillin), whereas domestic human C. jejuni isolates were more commonly resistant to ciprofloxacin, nalidixic acid, ampicillin and tetracycline. The resistance in foreign human isolates was significantly more common than among domestic isolates. PFGE analysis with KpnI restriction enzyme resulted in 59 different PFGE types among the poultry and human isolates. Three types were detected first in poultry meat and thereafter during the following month in domestic human samples, whereas the other conjoint types were detected only after many months. This study suggests that poultry products play only a minor role in human campylobacteriosis in the study area and that the resistance found in domestic human isolates is not likely related to retail poultry meat products.

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.

Nucleic acid sequence based amplification for the rapid and sensitive detection of Salmonella enterica from foods

The purpose of this study was to apply nucleic acid sequence-based amplification (NASBA) for the detection of Salmonella enterica serovar Enteritidis (S. Enteritidis) in representative foods. A previously reported primer and probe set based on mRNA sequences of the dnaK gene of Salmonella were used in this study. To test for possible food matrix inhibition and assay detection limits, 25-g samples of representative food commodities (fresh meats, poultry, fish, ready-to-eat salads and bakery products) were pre-enriched with and without S. Enteritidis inoculation. The NucliSens(R) Basic Kit, supplemented with enzymes from various other commercial sources, was used for RNA isolation, NASBA amplification and electrochemiluminescent (ECL) detection. The end point detection limit of the NASBA-ECL assay was equivalent to 101 CFU of S. Enteritidis per amplification reaction. When the assay was tested on noncontaminated foods, none of the food matrices produced false-positive results. Some of the food matrices inhibited the NASBA-ECL reaction unless the associated RNA was diluted 10-fold prior to amplification. For all food items tested, positive ECL signals were achieved after 18 h of pre-enrichment and subsequent NASBA at initial inoculum levels of 102 and 101 CFU per 25 g food sample. This rapid, semi-automated detection method has potential for use in the food, agricultural and public health sectors.

Evaluation of Time–Temperature Integrators for Tracking Poultry Product Quality throughout the Chill Chain

The goal of this study was to evaluate the application of one type of time–temperature integrator (TTI) to monitor the microbiological quality of ice-packed raw chicken drumsticks as a function of temperature exposure. A kinetics-based model was used to correlate the TTI chroma response to the number of bacteria on the drumstick surface under constant- and variable-temperature conditions. Two constant-temperature studies (4 and 15°C) and one variable-temperature study (4°C for 24 h, 15°C for 24 h, 4°C constant) were conducted to evaluate the applicability of the TTI under ideal and worst-case situations. During the constant-temperature studies, quality predictions made at the midpoint of the product shelf life were accurate within 15% for the observed bacterial populations. The accuracy of the TTI was marginal in the initial and final stages of the response period. During the variable-temperature study, the TTI response demonstrated positive history effects, whereby the observed rate constant is affected by previous temperature exposure. After the TTIs had been held at 15°C for 24 h, the TTI response rate constant observed during subsequent storage at 4°C was higher than what would be predicted for 4°C. Further work will be needed to develop a continuous TTI-based quality monitoring system. However, because the microbiological quality of fresh poultry could be reliably predicted with kinetic models, fresh poultry products would be excellent candidates for a TTI-based quality monitoring system.

The Economic Benefits of Nutrition Labeling: A Case Study for Fresh Meat and Poultry Products

New rules issued by the U.S. Department of Agriculture requiring provision of nutrition information on raw meat and poultry products may encourage consumers to make healthier food choices. Reduced intake of fat and cholesterol may prevent future cases of stroke, heart disease, and cancer. The benefits of these rules are estimated to be $62 to $125 million annually.