Variations in external and internal microbial populations in shell eggs during extended storage

The current project was conducted to determine the microbial quality of commercially processed shell eggs during extended storage. Unwashed eggs were collected at the accumulator before entering the processing line. Washed eggs were retrieved after placement in flats. All eggs were stored on pulp flats at 4 degrees C for 10 weeks. Twelve eggs from each treatment were rinsed on the day of collection and during each week of storage. After rinsing, eggs were sanitized in ethanol, and contents were aseptically collected. Total aerobes, yeasts and molds, Enterobacteriaceae, and pseudomonads were enumerated from shell rinses and pooled egg contents. During storage, no differences were found between unwashed and washed eggs for Enterobacteriaceae and pseudomonads in either shell rinses or contents. No differences were found between treatments for population levels of total aerobes or yeasts and molds in the egg contents throughout the storage period. Significant differences between treatments were found at each week of storage for external shell contamination by total aerobes. The highest unwashed egg contamination occurred at week 8 of storage and the lowest was at weeks 0 and 1 of storage. The highest shell contamination with aerobic bacteria on the washed eggs was found at week 0 of storage and the lowest was at week 7. Yeast and mold contamination determined by shell rinses was also significantly different between treatments at each week of storage. Commercially washed eggs were significantly less contaminated than were unwashed eggs for the populations monitored.     

Identification of Enterobacteriaceae from washed and unwashed commercial shell eggs

To evaluate the effect of processing on the safety and quality of retail shell eggs, a storage study was conducted with unwashed and commercially washed eggs. This work demonstrated that commercial processing decreased microbial contamination of eggshells. To know which species persisted during storage on washed or unwashed eggs, Enterobacteriaceae isolates were selected and identified biochemically. For each of three replications, shell eggs were purchased from a commercial processing plant, transported back to the laboratory, and stored at 4 degrees C. Once a week for 6 weeks, 12 eggs for each treatment (washed and unwashed control) were rinsed in sterile phosphate-buffered saline. A 1-ml aliquot of each sample was plated onto violet red bile glucose agar with overlay and incubated at 37 degrees C for 24 h. Following incubation, plates were observed for colonies characteristic of the family Enterobacteriaceae. A maximum of 10 isolates per positive sample were streaked for isolation before being identified to the genus or species level using commercially available biochemical strips. Although most of the isolates from the unwashed control eggs belonged to the genera Escherichia or Enterobacter, many other genera and species were identified. These included Citrobacter, Klebsiella, Kluyvera, Pantoea, Providencia, Rahnella, Salmonella, Serratia, and Yersinia. Non-Enterobacteriaceae also recovered from the unwashed egg samples included Xanthomonas and Flavimonas. Very few washed egg samples were contaminated with any of these bacteria. These data provide useful information on the effectiveness of processing in removing microorganisms from commercial shell eggs.     

Pathogen prevalence and microbial levels associated with restricted shell eggs

Restricted shell eggs that do not meet quality standards for retail but maintain acceptable quality for inclusion in further processed eggs are often diverted to further processing. A study was conducted to characterize the microbiological populations present on and in these eggs. On a single day, restricted eggs were collected from three shell egg processing plants a total of three times (replicates). Six shells or egg contents were combined to create a pool. Ten pools of shells and contents were formed for each plant per replicate. Shells and membranes were macerated in 60 ml of diluent. Contents were stomacher blended to form a homogeneous mixture. Total aerobic microorganisms and Enterobacteriaceae were enumerated. The prevalence of Salmonella, Campylobacter, and Listeria was determined by cultural methods. Average aerobic counts were 4.3 log CFU/ml for the shells and 2.0 log CFU/ml for the contents. There were plant x replicate differences for both (P < 0.05 and P < 0.01, respectively). The average Enterobacteriaceae level associated with the shell was 2.4 log CFU/ml and less than 0.1 log CFU/ml for the egg contents, with 36.7% of the samples being positive. One shell sample (0.5% of total samples) was Campylobacter positive. Two shell samples (1.1% of total samples) were Salmonella positive. Twenty-one percent of samples were positive for Listeria (33 shells and 5 contents). Although current pasteurization guidelines are based on Salmonella lethality, the results of this study reiterate the need to revisit the guidelines to determine the effectiveness for other pathogenic species.     

Impact of commercial processing on the microbiology of shell eggs

Shell egg microbiology has been studied extensively, but little information is available on how modern U.S. processing conditions impact microbial populations. As regulations are being drafted for the industry, such information can be important for determining processing steps critical to product safety. Five different shell egg surface microbial populations (aerobic bacteria, yeasts and molds, Enterobacteriaceae, Escherichia coli, and Salmonella) were monitored at 12 points along the processing line (accumulator, prewash rinse, washer 1, washer 2, sanitizer, dryer, oiler, scales, two packer head lanes, rewash entrance, and rewash exit). Three commercial facilities were each visited three times, a total of 990 eggs were sampled, and 5,220 microbiological samples were subsequently analyzed. Although variations existed in concentrations of microorganisms recovered from each plant, the patterns of fluctuation for each population were similar at each plant. On average, aerobes, yeasts and molds, Enterobacteriaceae, and E. coli prevalence were reduced by 30, 20, 50, and 30%, respectively, by the end of processing. The microbial concentrations (log CFU per milliliter) in the egg rinse collected from packer head lanes were decreased by 3.3, 1.3, 1.3, and 0.5, respectively, when compared with those of rinses collected from eggs at the accumulator. Salmonella was recovered from 0 to 48% of pooled samples in the three repetitions. Higher concentrations of Salmonella were recovered from preprocessed than from in-process or ready-to-pack eggs. These data indicate that current commercial practices decrease microbial contamination of egg shell surfaces.     

Survey of shell egg processing plant sanitation programs: effects on non-egg-contact surfaces

To successfully implement a hazard analysis critical control point plan, prerequisite programs are essential. Sanitation standard operating procedures are an important part of such a plan and can reduce contamination levels so that food safety and quality are not adversely affected. Noncontact surfaces in the shell egg processing plants can serve as a reservoir of cross-contamination. The objective of this study was to assess the efficacy of sanitation programs used in a variety of shell egg processing facilities (in-line, off-line, and mixed operations). Fourteen different noncontact surfaces were sampled in nine commercial facilities across the southeastern United States. Non-egg-contact surfaces were defined as those where the shell egg does not come into direct contact with the surface or with the fluid from that surface. Gauze pads soaked in sterile phosphate-buffered saline were used for sampling at the end of a processing day (POST) and again the next morning prior to operations (PRE). Aerobic plate counts (APCs) and numbers of Enterobacteriaceae were determined. No significant differences (P > 0.05) were found between POST and PRE counts for either population recovered from the 14 sampling sites. Only samples from the floor under the farm belts, nest-run loader, washers, and packer heads were reduced by 1 log CFU/ml of rinsate for APCs or Enterobacteriaceae counts. APCs of more than 10(4) CFU/ml of rinsate were recovered from many samples. Highest APCs were found on the floor under the farm belt and on shelves of the nest-run carts. High APCs were found on the wheel surface for off-line carts and on the loading dock floor. Highest Enterobacteriaceae counts were found in samples from the floor, drain, and nest-run egg cart shelves. A lack of significant difference between POST and PRE counts indicates that current sanitation programs could be improved. These data suggest that traffic patterns for the movement of eggs and materials through the plant should be reevaluated so that cross-contamination is reduced.     

Hazards with cracked eggs and their relationship to egg shell strength

BACKGROUND: This study examined the relationship between egg shell strength and the prevalence of cracked shells, plus the relationship between egg shell cracks and the presence of bacteria in the albumen of retail eggs. A total of 500 eggs was sampled from five supermarket stores. Each egg was assessed for shell cracks using a candling method. The strength of the shells was assessed using a penetrometer. Bacteria from the egg albumen were recovered on blood agar. RESULTS: The proportion of eggs that were cracked was on average 9%, and at one of the stores it was 17%. Albumen from eggs with gross cracks produced more abundant bacterial growth on blood agar compared to non‐cracked eggs, and contained a higher incidence of Gram negative bacteria. Campylobacter spp. were not recovered from any eggs. The shells in cracked eggs had lower Shore D durometer values indicating that they were physically weaker than non‐cracked eggs. CONCLUSIONS: Weaker shells were more prone to developing cracks, and cracked eggs were more likely to contain bacteria. There were substantial differences between supermarkets in the prevalence of eggs with cracked shells. Copyright © 2008 Society of Chemical Industry     

Identification of yeasts isolated from commercial shell eggs stored at refrigerated temperatures

Yeasts and molds can grow on or in eggs, causing spoilage. Washed and unwashed eggs (treatments) were collected aseptically on three separate days (replications) from a commercial processing facility and stored for 10 weeks at 4 degrees C. Ten eggs from each treatment were sampled weekly (110 eggs per treatment per replication). Yeasts and molds were enumerated from external shell rinses by plating onto acidified potato dextrose agar. Yeast colonies were picked randomly and stored for subsequent identification by gas chromatographic analysis of fatty acid methyl esters using the MIDI Microbial Identification System. Of 688 isolates analyzed, 380 were identified to genus or species. Genera identified by this method included Candida, Cryptococcus, Hansenula, Hyphopichia, Metschnikowia, Rhodotorula, Sporobolomyces, and Torulaspora. Candida spp. accounted for 84.5% (321 of 380) of the isolate identifications. Candida famata was the most prevalent species (n = 120), followed by Candida lusitaniae (n = 38). A group of 20 isolates was subjected to molecular or biochemical analyses for comparison with the MIDI results. Biochemical tests were performed using automatic and mini systems. Results of biochemical tests and ribosomal DNA sequencing were in agreement for 11 of the isolates, but only 7 of the 20 MIDI-identified isolates were in agreement with the sequencing results. C. famata, an anamorph of Debaryomyces hansenii var. hansenii, was the most commonly identified isolate by all methods. These data indicate that there was limited correlation between results obtained with the MIDI system and the information obtained from molecular databases. However, both systems were able to correctly identify C. famata, the species most often isolated throughout egg storage.     

Survey of shell egg processing plant sanitation programs: effects on egg contact surfaces

Sanitation standard operating procedures (SSOPs) are an integral component of process control and are often the first step in the implementation of food safety regulations. The objective of this study was to assess and compare the efficacies of sanitation programs used in a variety of shell egg processing facilities. In-line, off-line, and mixed operations were evaluated. Sixteen direct or indirect egg contact surfaces were sampled in various shell egg processing facilities in the southeast United States. Samples were collected at the end of a processing day (POST) and again the next morning before operations began (PRE). Total aerobic plate counts (APCs) were obtained and Enterobacteriacae were enumerated. No significant differences (P > 0.05) between POST and PRE bacterial counts were found for the 16 sampling sites. In general, high APCs were found on the wall of the recirculating water tank both POST and PRE. The APCs for the rewash belt were considerably high for all plants sampled. APCs were also high for the vacuum loaders. APCs for washers and washer brushes were relatively low for most plants sampled. PRE and POST levels of plant sanitation, as determined by direct microbial plating, did not differ significantly. At this point, it is difficult to draw definitive conclusions about how rigid SSOPs should be for the shell egg processing industry.     

Comparison of sponging and excising as sampling procedures for microbiological analysis of fresh beef-carcass tissue

Sponging and excising were evaluated as sampling procedures for microbiological analysis of beef-carcass tissue. Brisket tissue portions (10 x 10 cm) were inoculated with 2 ml of an Escherichia coli ATCC 25922 cell suspension (3 x 10(8)CFU/ ml). After 30 min, the portions were sampled by excising (EX) or swabbing (SP) with a sterile sponge and were analyzed for aerobic plate counts on tryptic soy agar and for total coliform counts and E. coli counts on Petrifilm E. coli count plates. Another set of inoculated samples was analyzed after being spray washed, in sequence, with water (6 s, 35 degrees C, 3.4 bar), acetic acid (2%, 6 s, 35 degrees C, 2.1 bar), water (20 s, 42 degrees C, 20.7 bar), and acetic acid (2%, 6 s, 35 degrees C, 2.1 bar). Additional samples were sampled for analysis after chilling at 7 degrees C for 24 h. Bacterial counts recovered were influenced (P < or = 0.05) by procedure of sampling (EX versus SP), time of sampling (0.5 versus 24 h), and by their interactions. Counts recovered 0.5 h after inoculation from unwashed or spray-washed samples were similar between the two sampling procedures (EX and SP). However, counts recovered after 24 h of sample storage were significantly (P < or = 0.05) lower for the SP compared with the EX procedure. The results indicated that as the carcass tissue was stored, recovery of bacteria by SP was less efficient than was recovery by EX.     

Optimizing irradiation treatment of shell eggs using simulation

Accurate dose calculation is needed to ensure proper irradiation process control to maintain the freshness of the product. Our objective was to establish the best irradiation treatment for shell eggs taking into account their different components (shell, albumen, yolk). Computer tomography (CT) data were used to generate a 3-D geometry to simulate dose distributions within 1 egg using a radiation transport code (MCNP5). Radiation energies used for simulation were 10 MeV (high-energy) and 1.35 MeV (low-energy) for electron beam, 5 MeV for X-rays, and 1.25 MeV for a gamma-rays source such as Co-60. Low-energy (surface) e-beam simulation indicated that electrons only penetrate up to the thin albumen (0.6 cm). Because of their irregular shape, shell eggs should be irradiated from the side (rather than from top or bottom) for better dose distribution. For high-energy e-beam simulation, the entire egg was irradiated and the best results were obtained when the egg was irradiated from both sides, showing a dose uniformity ratio (D(max)/D(min)) of 1.42. X- or gamma-ray source simulation from one side only, the dose uniformity ratio was 3.38 and 3.12, respectively. For surface-only irradiation, a low-energy e-beam provides a uniform dose distribution. To irradiate the entire egg, 2-sided high-energy e-beam sources are required for an efficient treatment. Unless the product rotates in front of the source, the dose uniformity ratio for X-ray or gamma ray is not adequate for shell egg treatment for pathogen decontamination purposes. Practical Application: Proper control of irradiation treatment of foods such as shell eggs is critical to ensure pathogen inactivation while maintaining product freshness. Simulation allows for accurate calculation of dose distribution within the egg to further establish the best irradiation scheme.     

合肥市售鸡蛋壳表面与内容物沙门氏菌污染的 检测及其分离株耐药性分析

目的 了解市售鸡蛋壳表面、内容物中沙门氏菌的污染情况及分离菌株的血清型分布与耐药性。方法 采用沙门氏菌常规检测法并结合PCR技术, 对采自合肥市农贸市场、超市的100枚鸡蛋进行检测; 利用国标法和K-B 纸片法对分离株进行血清型鉴定和抗生素药物敏感试验。结果 蛋壳表面沙门氏菌检出率为10%(10/100), 蛋内容物沙门氏菌检出率为1%(1/100); 11株沙门氏菌分离株血清型均为鸭沙门氏菌; 14种抗生素药物敏感试验中, 对青霉素100%耐受, 链霉素18.2%耐药, 36.4%中等耐药率, 其余抗生素均敏感。 结论 合肥市售鸡蛋壳表面的沙门氏菌检出率高于蛋内容物, 抗生素选择压力导致不同地区沙门氏菌分离株的血清型和耐药性有所不同。     

Effect of various refrigeration temperatures on quality of shell eggs

BACKGROUND: The objective of this study was to evaluate the effects of low storage temperatures on shell egg quality. RESULTS: Approximately 2100 shell eggs were collected and stored at ? 1.1, 0.6, 2.2, 3.9, 5.6 and 7.2 °C for up to 4 weeks. Eighteen eggs at each storage temperature were evaluated after 0, 2, 7, 14, 21 and 28 days of storage. Haugh units (HU), yolk index (YI), albumen pH (pHA), yolk pH (pHY) and angel food cake density (CD) were measured. Shell egg quality tended to be preserved better at below 2.2 °C, as high HU and YI values relative to eggs stored at 7.2 °C were determined on day 28. However, storage at ? 1.1 °C tended to cause the opposite effect, especially highly declined HU values over time. Significantly different HU values of shell eggs were measured after 14 days of storage, with eggs stored at 0.6 and 2.2 °C having the highest HU values, 80.42 and 77.97 respectively. CONCLUSION: A lower temperature limit for shell egg storage could be established between 0.6 and 2.2 °C, as both temperatures showed the highest HU values, 77.88 and 77.60 respectively, after 28 days of storage. Copyright © 2011 Society of Chemical Industry     

Effect of thermoultrasonication on Salmonella enterica serovar Enteritidis in distilled water and intact shell eggs

The combined effects of simultaneous application of ultrasonic waves and heat treatment (thermoultrasonication) on the survival of a strain of Salmonella enterica Enteritidis was studied in both distilled water and intentionally contaminated intact eggs immersed in water. Although minor differences were observed between parameters obtained for thermoultrasonic treatment of bacteria suspended in water and those attached to the shell egg, the thermoultrasonication effects were considered to be of the same level in the range of temperatures assayed (52 to 58 degrees C). This combined process presented a clearly higher killing effect than the heat treatment alone. It decreased the decimal reduction times (D-values) by 80 to 55%, respectively, in the range of temperatures for heat treatment when the organism was suspended in water, which means a 99.5% reduction (5D to >2D) of the original bacterial load versus a 90% reduction for the heat treatment alone. The practical implications of the phenomenon are discussed.     

Pasteurization of intact shell eggs

The feasibility of pasteurization for destruction ofSalmonella enteritidisin artificially- inoculated intact shell eggs was investigated. Water-bath and hot air ovens were used for pasteurization of intact shell eggs under different conditions using these two heating methods, either individually or in combination. Eggs pasteurized in a 57°C circulating water-bath for 25 min gave reductions inS. enteritidisATCC 13076 of about 3 log cycles whereas heating at 55°C in a hot air oven for 180 min gave a 5 log reduction ofS. enteritidis. A combin?ation of the two methods (water-bath heating at 57°C for 25 min followed by hot-air heating at 55°C for 60 min) produced 7 log reductions inS. enteritidisATCC 13076 in shell eggs. Examination of lysozyme activity and other physical properties of egg white upon heating indicated that the overall functionality of pasteurized shell eggs are acceptable under the heating conditions defined in this study. This process may be used to produce safe, pasteurized shell eggs.sed     

COMPARISON OF A PEROXIDASE-CATALYZED SANITIZER WITH OTHER EGG SANITIZERS USING A LABORATORY-SCALE SPRAYER

Microbial and foodborne pathogen contamination of eggs continues to represent an important public health concern. The goal of this study was to compare the efficacy of spraying shell eggs with PCC (peroxidase-catalyzed compound, Enzodine ^TM, Symbollon Corporation, Sudbury, MA) with that of other sanitizers in the reduction of surface microbial contamination using a laboratory-scale sprayer apparatus. Treatments were distilled-deionized water, PCC, chlorine (200 ppm), and quaternary ammonium (QA). Each egg was sprayed with 150 mL of the treatment over a 1 min period while being rotated at approximately 150 revolutions per min. Enumeration of aerobic plate populations indicated that all treatments (distilled-deionized water, chlorine, PCC, and QA) significantly reduced the viable aerobic bacterial populations and Salmonella typhimurium when compared to the nonsprayed dry egg control. Spraying eggs with PCC resulted in a 6 logarithmic reduction in viable S. typhimurium populations on egg shell surfaces. Unlike results found with aerobic bacterial populations, PCC was not as effective in reducing levels of S. typhimurium to the extent of the chlorine and QA treatments (greater than 6 logarithmic reduction) but greater than 3 logarithmic reduction was observed with PCC as compared to distilled-deionized water. This study suggests that PCC may be a viable alternative to chlorine and QA in the reduction of bacterial populations on shell egg surfaces and can be applied as a spray on egg shell surfaces.     

Detection of Salmonella enteritidis in shell and liquid eggs using enrichment and plating

Detection methods using various enrichment and plating media and immunoconcentration for Salmonella enteritidis in shell and liquid eggs were evaluated. For liquid egg samples naturally contaminated with S. enteritidis, pre-enrichment in 225 ml of buffered peptone water with cysteine followed by selective enrichment in 10 ml of tetrathionate broth was the superior, resulting in the detection of S. enteritidis in all samples on six of the seven types of selective agar substrate investigated. This enrichment procedure also enabled detection of S. enteritidis in most of artificially inoculated shell egg and pasteurized liquid egg samples.     

不同品种鲜蛋品质差异分析

目的探究褐壳蛋、粉壳蛋和白壳蛋3种类型鸡蛋的品质差异以及对于蛋粉加工的潜在影响。方法选用京红1号、京粉1号和京白1号所产的褐壳蛋、粉壳蛋和白壳蛋作为试验对象,对37周龄和51周龄蛋鸡所产3种类型鸡蛋的蛋品质进行分析比较。结果 37周龄和51周龄的白壳蛋蛋壳厚度、蛋壳比例和蛋壳强度均显著低于其他2个类型鸡蛋(P0.05);37周龄时3种类型鸡蛋的蛋黄水分含量没有显著性差异(P0.05);白壳蛋蛋清水分含量以及总水分含量均较其他2个类型鸡蛋要低。37周龄时褐壳蛋的蛋黄蛋白质和脂肪含量均显著高于其他2个品种,白壳蛋次之,粉壳蛋最低。37周龄时白壳蛋的蛋清蛋白质含量显著低于其他2个品种。由于蛋清中脂肪含量极少,本试验不予考虑。结论褐壳蛋加工成蛋粉后具有更好的营养价值,而白壳蛋可以提高蛋粉加工的产量。     

Inactivation of Salmonella enterica serovar Enteritidis on shell eggs by ozone and UV radiation

The presence of Salmonella enterica serovar Enteritidis in shell eggs has serious public health implications. Several treatments have been developed to control Salmonella on eggs with mixed results. Currently, there is a need for time-saving, economical, and effective egg sanitization treatments. In this study, shell eggs externally contaminated with Salmonella (8.0 x 10(5) to 4.0 x 10(6) CFU/g of eggshell) were treated with gaseous ozone (O3) at 0 to 15 lb/in2 gauge for 0 to 20 min. In other experiments, contaminated shell eggs were exposed to UV radiation at 100 to 2,500 microW/cm2 for 0 to 5 min. Treatment combination included exposing contaminated eggs to UV (1,500 to 2,500 microW/cm2) for 1 min, followed by ozone at 5 lb/in2 gauge for 1 min. Eggs that were (i) noncontaminated and untreated, (ii) contaminated and untreated, and (iii) contaminated and treated with air were used as controls. Results indicated that treating shell eggs with ozone or UV, separately or in combination, significantly (P < 0.05) reduced Salmonella on shell eggs. For example, contaminated eggs treated with ozone at 4 to 8 degrees C and 15 lb/in2 gauge for 10 min or with UV (1,500 to 2,500 microW/cm2) at 22 to 25 degrees C for 5 min produced 5.9- or 4.3-log microbial reductions or more, respectively, when compared with contaminated untreated controls. Combinations including UV followed by ozone treatment resulted in synergistic inactivation of Salmonella by 4.6 log units or more in about 2 min of total treatment time. Salmonella was effectively inactivated on shell eggs in a short time and at low temperature with the use of a combination of UV radiation and ozone.     

Correlation of eggshell strength and Salmonella enteritidis contamination of commercial shell eggs

Shell quality has been identified as a heritable trait that can be manipulated by genetic selection. Previous research has concluded that many methods of determining shell quality produce variable results. With the development of newer, more precise measuring technologies, shell strength can now be assessed in a consistent, objective fashion. A research project was conducted to determine what role shell strength might play in affecting external Salmonella Enteritidis contamination of egg contents. Visibly clean eggs were collected from an in-line shell egg-processing facility at the accumulator. Eggs were inoculated by dipping in a concentrated suspension of nalidixic acid-resistant Salmonella Enteritidis. After storage, eggs were assessed for shell strength and both external and internal Salmonella Enteritidis contamination. In the first study, there was a significant difference (P < 0.05) in shell strength among the three replicates. No differences between treatments were found for shell strength or Salmonella Enteritidis contamination of contents. In the second study, there were no replicate differences for any of the monitored factors. When rinsate and content samples were enriched, 100% of the rinsates were positive for Salmonella Enteritidis. No content samples were shown to be contaminated with Salmonella Enteritidis during direct plating, but 3 to 5% of the samples from each replicate were positive after enrichment. Correlation analysis of the results from each study found only weak correlations between shell strength and Salmonella Enteritidis contamination on eggshell surface or contents. Within the range of shell strengths recorded in this study, the correlation analysis suggests that shell strength does not play a major role in Salmonella Enteritidis contamination. Further work with eggs that represent a greater range of shell strengths could provide a clearer indication of the interaction of shell strength and Salmonella Enteritidis contamination.     

Prevalence of Salmonella spp. in poultry broilers and shell eggs in Korea

This study was conducted to determine the presence of Salmonella spp. in raw broilers and shell eggs in Korea. In total, 135 dozen shell eggs and 27 raw broilers were tested. None of the egg yolks were found to contain Salmonella organisms but Escherichia coli, Escherichia hermanii, and Citrobacter freundii were isolated from egg shells. Salmonella spp. were detected in 25.9% of raw broilers, and Salmonella serotypes isolated from raw broilers were Salmonella Enteritidis, Salmonella Virchow, and Salmonella Virginia. D-values and antibiotic resistance of Salmonella isolates were also investigated. D-values of Salmonella enteritidis, Salmonella Virginia, and Salmonella Virchow in tryptic soy broth at 55 degrees C were 2.36, 2.13, and 0.70 min and 0.53, 0.37, and 0.20 min at 60 degrees C, respectively. All Salmonella isolates showed multiple antibiotic resistance patterns and were resistant to penicillin and vancomycin. One strain of Salmonella Enteritidis showed resistance to 12 antibiotics used in this study.