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In order to investigate the effect of conventional packaging forms on the freshness of market shell eggs, this research investigated shell egg freshness of Roman pink in paper-based packaging without overlapped eggs arrangement, paper-based packaging with overlapped eggs arrangement, foam-based cushioning packaging, carton-based packaging, plastic-based packaging 5 groups. The shell eggs were stored at 25 ℃ for 30 d, and evaluated weight loss, air space diameter and height, yolk index, Haugh unit, thick-to-thin albumen ratio and albumen pH at 0, 10, 20, 30 d. The results showed that in shell eggs treated with paper-based packaging with overlapped eggs arrangement had significantly (P

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Shell egg freshness is the key factor of evaluating egg quality. This review summarizes evaluation methods, influence factors of shell egg freshness, methods of retarding shell egg freshness deteriorations and future research directions of shell egg freshness. The results shows that egg freshness can be possibly evaluated by combination of destructive testing technology and non-destructive testing technology in an objective, dynamic and on-line manner. Hen age, diet, storage, transportation and environmental conditions can make a great influence on shell egg freshness. The characteristics of shell egg freshness can be possibly well maintained by adopting young hen, balanced nutrition diets, low temperature storage and avoiding mechanical damages during transportation and storage. Sterilization, packaging and coating methods can probably retard shell egg freshness deteriorations. Partially/totally adopting green, high efficient and energy-saving non-conventional food sterilization methods, and active, biodegradable and intelligent packaging/coating methods can possibly avoid microbial spoilage and retard egg freshness deteriorations during egg preservation. More researches of non-destructive testing technologies, diet formulations, simulating actual production, storage, transportation and sales, as well as optimization of non-conventional food sterilization-packaging and coating technologies need to be further explored, thus achieving quality improvement and industry promotion of shell eggs.

ABSTRACT: The purpose of this study is to investigate the characteristics of egg consumption in China and the production of functional eggs, and finally enrich the types of shell egg products. Trial 1 explored the influence of egg quality on Chinese consumers' willingness to purchase eggs through a questionnaire, which investigated 1,317 consumers' preferences for egg appearance, factors influencing egg purchase, and purchase of functional eggs. The results showed that about 65% of respondents ate more than 4 eggs per wk, pink eggs were the most popular in China, about 65% of consumers preferred eggs with an egg weight of 48 to 58 grams. For functional eggs, 75.32% of consumers have never heard of them. Preferences for eggshell color and yolk color varied by geographic region, with darker colors preferred in Northeast China. Based on the survey results of functional eggs consumption in Trial 1, the dwarf layers of China Agricultural University were used in Trial 2 to produce functional eggs. The eggs are small and pink in color, which is in line with the preferences of Chinese consumers. Three hundred dwarf layers were divided into 4 groups, using the linseed oil added, marigold extract added, and yeast selenium added diets to produce normal, n-3 fatty acid-enriched, lutein-enriched and selenium-enriched eggs by feeding for 28 d, determined the eggs’ nutrient content and egg quality. The results showed that the n-3 fatty acid, lutein and selenium contents of the eggs of dwarf layers were significantly increased by changing the diets and did not affect the egg weight, eggshell strength, Haugh units or the proportion of egg parts. The results of this study are helpful to understand the trend of egg consumption preferences in China, and on this basis to produce functional eggs that meet the consumers’ expectations.

Thermal pasteurization of shell eggs, at various time-temperature combinations, has been proposed previously and implemented industrially. This study was conducted to determine if shell egg heating rate, which varies with different pasteurization implementations, alters the Salmonella enterica serovar Enteritidis response to different stresses or expression of virulence. Shell eggs, containing Salmonella Enteritidis in yolk, were subjected to a low (2.4°C/min) or a high (3.5°C/min) heating rate during treatments that mimicked the pasteurization temperature come-up stage. The low heating rate protected Salmonella from the following processes: (i) lethal heat at the holding stage, (ii) loss of viability during 8-h cooling after heating, and (iii) sequential antimicrobial ozone treatment. Transcriptional analysis using Salmonella reporter strains revealed that the heat stress response gene grpE was transcribed at 3-fold-higher levels (P = 0.0009) at the low than at the high heating rate. Slow heating also significantly increased the transcription of the Salmonella virulence-related genes sopB (P = 0.0012) and sseA (P = 0.0006) in comparison to fast heating. Salmonella virulence was determined experimentally as 50% lethal dose (LD50) values in an in vivo model. The slow heat treatment mildly increased Salmonella Enteritidis virulence in mice (LD50 of 3.3 log CFU), compared to that in nontreated yolk (LD50 of 3.9 log CFU). However, when ozone application followed the slow heat treatment, Salmonella virulence decreased (LD50 of 4.2 log CFU) compared to that for heat-treated or nontreated yolk. In conclusion, heating shell eggs at a low rate can trigger hazardous responses that may compromise the safety of the final pasteurized products but following the thermal treatment with ozone application may help alleviate these concerns. [ABSTRACT FROM AUTHOR]

In the United States, all shell eggs processed under the USDA Agricultural Marketing Service voluntary grading standards must receive a shell sanitizing rinse of 100–200 ppm chlorine or its equivalent after leaving the washing process. A study was conducted to determine the concentration of peroxyacetic acid (PAA) which would be equivalent to 100–200 ppm chlorine (Cl) in reducing target organisms under the required washing conditions for shell eggs. Three isolates of Salmonella spp. (Enteritidis, Braenderup, and Typhimurium), as well as Enterobacter cloacae were used as inocula. Sanitizing treatments were negative control; deionized water; 100 and 200 ppm Cl; and 50–500 ppm PAA (7 concentrations). Considering all isolates tested, 100 and 200 ppm chlorine had 2.6 and 2.3 log cfu/mL cultural organisms remaining on shell surface; 50 and 100 ppm peracetic acid had 1.9 and 1.0 log cfu/mL cultural organisms remaining, respectively, compared with untreated control average of 3.8 log cfu/mL (P 250 ppm did not produce significant reductions in microbial populations as PAA concentration increased. Culturing for the prevalence of viable and injured organisms, 400–500 ppm PAA resulted in fewer eggs (P

Egg safety and quality is a long-standing concern for producers and consumers. Salmonella enterica serovar Enteritidis (Salmonella Enteritidis) is the prevalent egg-product-related foodborne pathogen. The treatment with organic acids, including lactic acid, for the elimination and control of foodborne pathogens is generally recognized as safe, and is widely applied in many foods. In this study, we found that spraying with 2% lactic acid on the eggshell surface effectively reduced Salmonella Enteritidis counts. Agar-filled eggs were used to study the bacterial penetration of the eggshell (eggshell and membranes), and the contamination of the whole egg contents was investigated. No significant differences were observed between the Salmonella Enteritidis penetration in lactic acid sprayed and unsprayed eggs stored at 4 °C. The Haugh unit, albumin pH, and eggshell strength values were similar in the sprayed and washed eggs. Average Haugh unit scores for sprayed eggs were still Grade A within 3 weeks. However, the lactic acid treatment decreased the eggshell strength and cuticle layer thickness. SEM observations confirmed that spraying of lactic acid damaged the cuticle integrity. The results from our research will indicate that lactic acid spray is highly effective in reducing Salmonella contamination on the eggshell surface, but trans-shell penetration was demonstrated in the eggs stored at room temperature. Consequently, low-temperature storage is important for the prevention of recontamination of the egg after spraying. • Spraying with lactic acid on the eggshell surface effectively reduced Salmonella Enteritidis contamination. • No significant effect of lactic acid spraying was recorded on Salmonella Enteritidis penetration at 4 °C. • Salmonella penetration was correlated with the coverage of cuticle layer. • Low-temperature storage is effective at inhibiting SE recontamination of the egg after spraying. [ABSTRACT FROM AUTHOR]

Summary: The existing radio frequency (RF) shell egg pasteurisation method, while 60% faster than the industrial hot water method, requires manual rotation of the eggs and expensive deionised water. Therefore, the RF pasteurisation equipment was redesigned to automate egg rotation and use inexpensive tap water. A two‐step process heated eggs for 6 min with RF and then for 15 min with 56.7 °C water. The 21‐min combination process reduced Salmonella Typhimurium in eggs by 6.1 log without affecting the appearance of the albumen, whereas processing with 56.7 °C water alone required 60 min to reduce Salmonella by 5.0 log and clouded the albumen. Angel food cakes made from 21 min RF eggs had significantly greater volumes (P < 0.0001) than those from 60‐min hot water eggs. The improved RF process produced better eggs and cakes than those from the industrial hot water process and is now commercially feasible. The radio frequency (RF) pasteurisation process was improved by automating it and reducing its cost. Using the new RF equipment, Salmonella in shell eggs was reduced by 99.9999% in 21 min which is approximately one‐third the time of the existing industrial pasteurisation process. RF pasteurisation maintained the fresh appearance of egg whites and produced significantly better angel food cakes compared to those from the industrial process. [ABSTRACT FROM AUTHOR]

Egg is a regularly consumed food item. Currently, chlorinated water washing is the most common practice used to disinfect eggs, but this process has a negative environmental impact. A new physical technique, plasma-activated water (PAW), has been demonstrated to possess effective antibacterial activities without long-term chemical residue. In this study, air PAW was used to inactivate Salmonella enterica serovar Enteritidis on shell eggs. Different combinations of activation parameters, including water sources (reverse osmotic (RO) water, tap water), power (40 W, 50 W, 60 W) and activation time (10 min, 20 min, 30 min), were evaluated. The oxidation−reduction potential (ORP) and pH values of each combination were measured, and their antibacterial activity was tested in a bacterial suspension. Higher antibacterial activities, higher ORP values, and lower pH values were obtained with higher power, longer activation time, and lower water hardness. The antibacterial activities of PAW decreased rapidly by increasing the storage time both at room and refrigeration temperatures. Afterwards, RO water was pre-activated for 20 min at 60 W, and then the eggs inoculated with S. enteritidis were placed into PAW for 30 s, 60 s, 90 s, or 120 s with a plasma on-site treatment in the water. More than a 4 log reduction was obtained with 60-s and 120-s treatments. The results showed that the freshness indexes of the eggs treated with PAW were similar to those of the untreated controls and better than those of the eggs treated with commercial processes. In addition, observation under a scanning electron microscope also showed less surface damage of the cuticle on the PAW-treated eggs than on the commercially treated eggs. The results of this study indicate that PAW could be an effective antibacterial agent with less damage to the freshness of shell eggs than commercial methods.

Salmonella Enteritidis (SE) prevalence in eggs is a major concern to the egg industry. Some research has shown that egg sweating can increase Salmonella penetration into egg contents when refrigerated eggs are moved to a warmer temperature. This occurs when eggs are tempered before wash, to minimize thermal cracks. The effect of egg sweating on SE penetration into shell eggs over a 6 week storage period at 4°C was assessed. A 2 × 2 factorial of SE inoculation and egg sweating was utilized. Treatments included (SES) nalidixic acid (NA)-resistant SE inoculated and sweated, (SENS) NA-resistant SE inoculated and not sweated, (NSES) buffered peptone water (BPW) inoculated and sweated, and (NSENS) BPW inoculated and not sweated. Eggs were inoculated with 108 SE. Eggs formed condensation for approximately 17 min in a 32°C incubator. Shell rinse, shell emulsion, and egg contents were sampled then enumerated and assessed for prevalence of SE over a 6 wk storage period at 4°C. After wk 1, the SENS shell rinse had higher SE counts (0.32 log10 CFU/mL) than the other 3 treatments, where no SE was enumerated. A significant week by treatment interaction was found for the shell rinse SE detection (P < 0.05). In subsequent weeks, no SE counts were obtained from the egg shell rinse, shell emulsion, or egg contents. The SENS shell rinses had significantly higher SE prevalence than the SES rinses in weeks 1 (100% vs. 34.3%), 2 (57.6% vs. 22.2%), and 3 (38.2% vs. 11.1%) (P < 0.05). In samples from weeks 4, 5, and 6, there was no difference in SE prevalence between SES and SENS. Egg sweating did not increase SE penetration into the shell emulsion across treatment or week (P < 0.05). The decreasing trend of SE prevalence obtained over the study period indicate that refrigeration is effective at inhibiting SE growth. These results indicate that egg sweating occurring under common US egg handling practices is not harmful to egg safety. [ABSTRACT FROM AUTHOR]

The interior of the eggs obtained from healthy hens might be accepted to be free of microorganisms while the outer shell surface might include various microorganisms including pathogens. These microorganisms might pass through micro-cracks in the shell, or egg constituents might be contaminated while the shells are broken by accident or for process related purposes. These cause high microbial risk. Various surface decontamination techniques for shell eggs are applied, and thermal techniques have a certain limitation not to affect the functional properties of egg constituents especially egg white. Infrared application for surface decontamination is one suggested industrial application, and like all the other thermal methods, surface temperature of the shell should not exceed a certain value and must be determined in a quick and accurate manner. Thermocouple measurements bring certain difficulty for surface temperature determination. Hence, use of more convenient methods is required. Therefore, in this study, an infrared thermography method was improved for surface temperature measurement of the eggs undergoing an infrared surface decontamination process. [ABSTRACT FROM AUTHOR]

Hedonic modeling and retail scanner data were utilized to investigate the influence of local, organic, nutrition benefits, and other attributes of shell eggs on retail price premium in Hawaii. Within a revealed preference framework, the analysis of local and organic attributes, simultaneously, under a single unified setting is important, as such work is highly deficient in the published literature. This paper finds high to moderate price premiums in four key attributes of shell eggs -- organic (64%), local (40%), nutrition benefits claimed (33%), and brown shell (18.4%). Large and extra-large sized eggs also experience price premiums over medium sized eggs. With each larger packing size, the estimated coefficients were negative, indicating a price discount, relative to the baseline packing size. However, there is no evidence to support the overwhelming influence of "local" over "organic", as hypothesized in other research work. Overall, the findings in this paper suggest industry producers and retailers should highlight and market effusively the primary attributes of their shell eggs, including "local", to remain competitive in the marketplace. Effective communication channels are crucial to delivering the product information, capturing the attention of consumers, and securing retail sales. [ABSTRACT FROM AUTHOR]

To determine the prevalence of Salmonella serotype Enteritidis in eggs in South Korea, we conducted a microbiological survey of commercially available eggs produced in conventional or organic farms during the period from 2010 to 2012. The contents of 7,000 raw shell eggs (6,000 of conventional and 1,000 of organic origin) were examined to evaluate the extent and type of Salmonella Enteritidis contamination. A total of 26 salmonellae (7.4% of all pooled samples) were isolated from 350 homogenized pools, each containing the contents from 20 eggs. An unexpected and particularly surprising finding was that all the Salmonella isolates were serotyped as Salmonella Gallinarum. Salmonella Gallinarum was more common in eggs from organic farms: 10 of 50 egg pools (20.0%) from organic and 16 of 300 egg pools (5.3%) from conventional farms tested positive for Salmonella Gallinarum. However, organic and conventional isolates showed similar antimi- crobial susceptibilities. All the isolates and a vaccine strain, SG 9R, which has been widely used in South Korea, were further characterized using the automated repetitive sequence-based PCR (rep-PCR) system, DiversiLab, to ascertain the molecular subtypes and to identify differences from the vaccine strain. The rep-PCR identified 2 distinct clusters among the 26 Salmonella Gallinarum isolates with a greater than 96% similarity index. These were clearly differentiated from the vaccine strain, SG 9R, with which there was a less than 86% similarity index. We found there was low genetic heterogeneity among isolates within each cluster and were able to distinguish wild type strains from the live vaccine strain (SG 9R) using the DiversiLab system. [ABSTRACT FROM AUTHOR]

Salmonella, a member of the bacterial family Enterobacteriaceae, may be recovered from foods and processing facilities. High levels of Enterobacteriaceae in the processing plant environment can be an indication of inadequate sanitation. This experiment was designed to determine if nest run egg carts serve as reservoirs for Salmonella. Eggs that are produced by hens not housed in buildings connected to the processing plant are referred to as nest run. Many of these eggs are transported to a central processing facility before they are washed, graded, and packed. Two plants in the Southeastern United States were sampled; one was a mixed operation and the other was an offline operation. On each of 3 visits, 5 shelves on each of 5 carts were sampled (n = 25/visit). A 12 x 12 cm area on each shelf was swabbed with a sterile gauze pad moistened with PBS and transported on ice back to the laboratory. Each swab was preenriched in buffered peptone at 37°C for 24 h, selectively enriched using TT and Rappaport-Vassiliadis broth at 42°C overnight, then plated onto brilliant green sulfa and XLT-4 incubated at 37°C for 24 h. Presumptive colonies were transferred to lysine iron agar and triple sugar iron slants for 24 h at 37°C. Isolates with presumptive reactions were confirmed using commercial polyclonal antisera. After initial confirmation, serogrouping was performed using commercial antisera. Mixedoperation swab samples were 12% positive for Salmonella, whereas offline samples were 36% positive for Salmonella; isolates were confirmed as serogroups B, CI, and C2. Kauffman-White serotyping was performed by a contract laboratory. Serotypes (n = 30) recovered were Anatum, Heidelberg, Infantis, Kentucky, Mbandanka, and Typhimurium. This work demonstrated that nest run egg carts may serve as reservoirs for Salmonella in the shell egg processing environment. [ABSTRACT FROM AUTHOR]

Eggs from alternative production practices are a growing niche in the market. Meeting consumer requests for greater diversity in retail egg options has resulted in some unique challenges such as understanding the food safety implications of eggs from alternative production practices. A study was conducted to determine what, if any, differences exist between nest run conventional cage-produced eggs and free range-produced eggs. A sister flock of brown egg layers was maintained in conventional cage and free-range production with egg and environmental sampling every 6 wk from 20 to 79 wk of age. Aerobic, coliform, and yeast and mold populations were monitored. Environmental microbial levels were not always indicative of egg contamination levels. When significant differences (P < 0.05 and P < 0.0001, dependent on season) were observed among treatments for coliforms, shell contamination levels of free-range nest box eggs and free-range floor eggs were always greater than those of conventional cage eggs, which remained low throughout the study (0.42-0.02 log cfu/mL). Shell yeast and mold levels were significantly greater in free-range floor eggs than in free-range nest box eggs and conventional cage eggs throughout the entire study. Egg contents contamination levels were extremely low for all monitored populations and treatments. Season of the year played a role in both environmental and egg microbial levels. Winter had the lowest levels of all populations monitored for all treatments, except for aerobic free-range floor egg shell emulsions, which were increased (3.6 log cfu/mL). Understanding the differences in microbial populations present on conventional cage-produced and free range-produced eggs can lead to the development of effective cleaning procedures, enhancing food safety. [ABSTRACT FROM AUTHOR]

The aim of this study was to compare technological properties (gel hardness, foam drainage, and meringue crispness) of albumen of nonpacked table eggs (control) with those of eggs packed in high-barrier plastic pouches with 3 modified atmosphere packaging (MAP) conditions (air, 100% N2, and 100% CO2) during 28 d of storage at 25°C. The values of gel hardness for the control sample showed an increasing trend, demonstrating the highest values throughout the experiment duration compared with the other samples. This behavior was probably attributable to the pH increase detected only for this sample during storage (from 8.82 ± 0.06 for fresh egg to 9.96 ± 0.06 at the end of the experiment). Air and N2 samples showed constant and similar hardness values during storage. The hardness of coagulated albumen showed a strict correlation with raw albumen pH (r2 = 0.929; P < 0.001). Other than reducing albumen pH during storage, MAP with CO2 caused the formation of a soft and puffy coagulum with very low hardness, reaching the lowest value of 1.26 ± 0.38 N after 4 d of storage, that slowly increased to 2.11 ± 0.49 N at the end of the experiment. Foam stability decreased during storage for all samples, but CO2 eggs showed a significantly (P < 0.05) higher foam stability than fresh eggs until 15 d, reaching values similar to those of the other samples only at the end of the storage time. Packing eggs in CO2 promoted an improvement of meringue crispness. The application of this atmosphere could ameliorate the quality characteristics of albumen-based food products. Commercially, CO2 MAP could provide an albumen-based ingredient tailored to maximize the characteristics needed in the final product (e.g., fresh shell eggs special for meringue preparation) that could give an added value to the product. [ABSTRACT FROM AUTHOR]

Three thermal processes viz. dry (55°C, 2 h), moist (57°C, 5 min) and microwave (power 9, 20 sec) were studied to determine their efficacy for the pasteurization of intact chicken eggs based on the extent of inactivation of artificially inoculated Salmonella typhimurium (ST) in the yolk of shell eggs and alteration in albumen protein solubility (APS). Moist heat treatment was superior to others as it brought about 2 log cfu/ml reduction of inoculated ST in much less time than dry heating but changes in APS were not significant. Subsequent quality evaluation of normal (uninoculated) eggs subjected to moist heat pasteurization during 15 days of ambient (35°C, 36% RH) (35 ± 0.5°C, 36 ± 2% RH)storage revealed no significant effect on percent loss in egg weight, albumen pH, viscosity of albumen and yolk and thiobarbituric acid values between pasteurized and unpasteurized eggs. Pasteurization had no adverse effect on foam volume and foam stability of albumen during storage in comparison to those of raw eggs. Naturally occurring aerobic mesophilic bacteria, coliforms, staphylococci, yeast and moulds on the egg shell surface and in egg contents got markedly reduced by pasteurization of shell eggs and their multiplication also retarded during storage. Both pasteurized and raw eggs remained fairly acceptable sensorily up to 10 days of storage at ambient conditions. [ABSTRACT FROM AUTHOR]

Cracks in the shell surface compromise the primary barrier for external microbial contamination of the egg. Microcracks are very small cracks in the shell surface that are difficult to detect by human graders. New technology has been developed that uses modified pressure and imaging to detect microcracks in eggs. Research has shown the system to have an accuracy of 99.6% in detecting both cracked and intact eggs. A study was undertaken to determine if quality differences existed between modified pressure imaged and control eggs during extended cold storage. Three replicates were conducted with eggs stored at 4°C for 5 wk with weekly quality testing. The physical quality factors monitored were Haugh units, albumen height, egg weight, shell strength, vitelline membrane strength and elasticity, and whole egg total solids. All measurements were conducted on individual eggs (12/treatments per replicate) each week with the exception of whole egg solids, which were determined from 3 pools (4 eggs each)/treatment per replicate each week. Percentage of whole egg total solids was the only significant difference (P < 0.05) between treatments (23.65% modified pressure imaged and 23.47% control). There was a significant difference (P < 0.05) for egg weight between replicates (60.82, 58.02, and 60.58 g for replicates 1, 2, and 3, respectively). Therefore, imaging eggs in the modified pressure system for microcrack detection did not alter egg quality during extended cold storage. Utilizing the modified pressure crack detection technology would result in fewer cracked eggs reaching the consumer, consequently enhancing food safety without affecting product quality. [ABSTRACT FROM AUTHOR]

There are a number of specialty shell eggs available to consumers in the US retail market. A survey consisting of white and brown large shell eggs with various production and nutritional differences (traditional, cage-free, free-roaming, pasteurized, nutritionally enhanced, and fertile) was conducted to determine if physical quality and compositional differences exist. Identical brands of eggs were purchased from the same retail outlets on 3 occasions (replicates) in a single city. The average range of time from processing to purchase for all eggs was 7.67 to 25.33 d, with traditional white eggs in retail having the shortest time. Haugh unit values ranged from 66.67 (cage-free, docosahexaenoic acid, and n-3 enhanced) to 84.42 (traditional white). Albumen height followed a similar pattern. Egg weight was greater for brown eggs (61.12 vs. 58.85 g). Brown eggs also had greater static compression shell strength than white eggs (4,130.61 vs. 3,690.31 g force). Vitelline membrane strength was greatest for traditional brown eggs (2.24 g force). Percentage of total solids and crude fat was greatest in the cage-free, n-3-enhanced white eggs (25.07 and 11.71%, respectively). Although significant differences were found between white and brown shell eggs and production methods, average values for quality attributes varied without one egg type consistently maintaining the highest or lowest values. [ABSTRACT FROM AUTHOR]

Studies were conducted to determine the effects of various sanitizing compounds on the microbial and physical quality of shell egg processing vacuum loader cups. The sanitizing compounds used were as follows: sterile, distilled water; 200 μL/L of sodium hypochlorite; 200 pL/L of calcium hypochlorite; and 200 μL/L of peracetic acid. In the microbial inoculation study, cups were inoculated with Enterobacter cloacae because it was the most common isolate from a commercial study examining the flora found on vacuum loader cups. In all 3 replicates, aerobic plate counts and Enterobacteriaceae levels were similar for the clean control cups and the cups from the 2 chlorine treatments. Physical quality was measured via serial static compression testing using texture profile analysis. The serial compression mimicked the movement of the vacuum loader cups on the processing line. The strength of the vacuum loader cups was enhanced with exposure to any sanitizer treatment, including distilled water, compared with the controls throughout the 20 applications of the sanitizers. Durometer measurements were not consistent in monitoring vacuum loader cup quality and were determined to not he effective assessments for this application. The use of 200 pL/L of sodium hypochlorite or 200 1wL/L of calcium hypochlorite successfully reduced microbial contaminants, had a positive effect on vacuum loader cup physical quality, and should be considered when developing sanitation programs for shell egg processing facilities. [ABSTRACT FROM AUTHOR]

Current egg washing practices use wash water temperatures averaging 49°C and have been found to increase internal egg temperature by 6.7 to 7.8°C. These high temperatures create a more optimal environment for bacterial growth, including Salmonella Enteritidis if it is present. Salmonella Enteritidis is the most common human pathogen associated with shell eggs and egg products. Its growth is inhibited at temperatures of 7.2°C and below. The objective of this study was to determine if commercially washing eggs in cool water would aid in quickly reducing internal egg temperature, preserving interior egg quality, and slowing microbial growth. During 3 consecutive days, eggs were washed using 4 dual-tank wash water temperature schemes (HH = 49°C, 49°C; HC = 49°C, 24°C; CC = 24°C, 24°C; CH = 24°C, 49°C) at 2 commercial processing facilities. A 10-wk storage study followed, in which vitelline membrane strength, Haugh unit, and aerobic microorganisms and fungi (yeasts and molds) were monitored weekly. As storage time progressed, average Haugh unit values declined 14.8%, the average force required to rupture the vitelline membrane decreased 20.6%, average numbers of bacteria present on shell surfaces decreased 11.3%, and bacteria present in egg contents increased 39.5% during storage. Wash water temperature did not significantly affect Haugh unit values, vitelline membrane strength, or the numbers of aerobic microorganisms and fungi within the shell matrices of processed eggs. Results of this study indicate that incorporating cool water into commercial shell egg processing, while maintaining a pH of 10 to 12, lowers postprocessing egg temperatures and allows for more rapid cooling, without causing a decline in egg quality or increasing the presence of aerobic microorganisms and fungi for approximately 5 wk postprocessing. [ABSTRACT FROM AUTHOR]

This study was made to examine the combined effects of stored temperature and carbon dioxide atmosphere on shell egg quality. The shell eggs were packed into polyethylene terephthalate/polyethylene (PET/PE) pouches and stored at 0 °C (super chilling), 10 °C, and 20 °C, respectively for 90 d. The atmospheric carbon dioxide concentration was controlled to obtain the 3 concentration levels of high (about 2.0%), medium (about 0.5%), and low (below 0.01%). Changes in Haugh unit (HU) values, weakening of vitelline membranes, and generation of volatiles were analyzed to evaluate the freshness of shell eggs. Results showed that, compared with the other combinations, the technique of super chilling and high carbon dioxide concentration enabled shell eggs to be most effectively stored for 90 d, based on estimations of the statistical significances of differences in HU values, and on maintaining the initial HU values during storage. In addition, the storage of shell eggs using this combination technique was found to significantly prevent the weakening of the vitelline membrane based on the estimations of numbers of eggs without vitelline membrane breakage when eggs broke, and significantly lowered the incidence of hexanal in the yolk from exposure to the gas chromatographic-mass spectrometric analyses of volatiles. Thus, these results confirmed that the combination of super chilling and high carbon dioxide concentration was the most effective technique for preserving shell eggs during a long term of 90 d compared with other combination techniques. [ABSTRACT FROM AUTHOR]

Enterobacteriaceae, including Salmonella, may be recovered from foods and processing facilities. High levels of Enterobacteriaceae in the processing plant environment can be an indication of inadequate sanitation. This experiment was designed to determine if nest run egg carts serve as reservoirs for Enterobacteriaceae. Eggs that are produced by hens not housed in buildings connected to the processing plant are referred to as nest run. Many of these eggs are transported to the plant on carts to be processed. Two plants in the southeastern United States were sampled. On each of 3 visits, 5 shelves on each of 5 carts were sampled (n = 25/visit). A 12 x 12 cm area on each shelf was swabbed with a sterile gauze pad moistened with PBS and transported on ice back to the laboratory. Enterobacteriaceae were enumerated using violet red bile glucose agar incubated at 37°C for 24 h. There was 100% prevalence for Enterobacteriaceae at plant A with an average 3.8 log10 cfu/mL swab diluent. Plant B had 90% prevalence for Enterobacteriaceae with an average 3.2 log10 cfu/mL swab diluent, Two randomly selected isolates from each positive sample were recultured 3 times to increase the likelihood of clonality and were then identified biochemically. Of the 124 isolates analyzed, genera identified were Citrobacter spp., Escherichia spp., Enterobacter spp., Klebsiella spp., Hafnia spp., Kluyvera spp., Leclercia spp., and Salmonella spp. Pseudomonas spp. was the only non-Enterobacteriaceae identified by our methods. This work demonstrates that nest run egg carts serve as reservoirs for Enterobacteriaceae in the shell egg processing environment. [ABSTRACT FROM AUTHOR]

Microwaves have been shown to cause thermal as well as nonthermal destruction of pathogens such as Salmonella, which can be found in shell eggs. The objective of this study was to determine if using microwave technology would cause detrimental quality effects in shell eggs. Treatments included control (no treatment) and microwave-treated (20 s) shell eggs. There were no differences in mineral content, fatty acid profile, Haugh units, broken-out score, yolk index, emulsion stability, pH of whole egg, and foaming capacity between 2 treatments (P ⩾ 0.05). At 0 and 30 d, there were no noticeable differences in H2O activity between 2 treatments. The foaming stability and albumen thermocoagulation of microwave-treated eggs were significantly higher than control eggs (P ⩽ 0.05). The control eggs had significantly higher emulsion capacity and lower vitelline membrane strength than the micro- wave-treated eggs (P ⩽ 0.05). Poached eggs were evaluated by sensory testing for hardness, yolk color, and albumen color, and there are no noticeable differences at 0, 15, or 30 d. At 0 d, the color of control albumen was more yellow than the microwave-treated albumen, and the chalazae of the microwave-treated eggs was more attached than the control eggs (P ⩽ 0.05). The TBA reactive substances were similar for 2 treatments at 0, 15, and 30 d. Peroxide values were significantly higher in the microwave-treated eggs at d 0 (P ⩽ 0.05), but at 15 and 30 d, no prominent differences in peroxide values were noted (P ⩾ 0.05). Therefore, microwave technology can be applied to shell eggs without causing detrimental effects to quality. [ABSTRACT FROM AUTHOR]

Cleaning and sanitation are paramount in food processing. Gaining an understanding of the microbial populations present in a processing facility can help in the development of effective and efficient cleaning. The current study was undertaken to gain a better understanding of the Enterobacteriaceae present on vacuum loader cups used in shell egg processing to transfer nest run eggs to the processing line. Twenty cups were rinsed on each of 3 visits to both an off-line operation and a mixed operation. A total of 442 Enterobacteriaceae isolates were biochemically identified from vacuum loader cup rinses. The predominant genera isolated from the 2 facilities were Enterobacter, Klebsiella, Escherichia, Citrobacter, and Serratia. The primary organisms from the off-line facility were Klebsiella oxytoca, Enterobacter amnigenus 2, and Klebsiella pneumoniae. The isolates found in the greatest proportion from the mixed operation were Enterobacter cloacae and Klebsiella oxytoca. A total of 18 genera were recovered from the 2 facilities, with 9 being present in both processing facilities. The findings of this study can be used in assessing the sources of bacterial contamination in egg processing and in developing more effective, targeted cleaning programs for processing equipment and facilities. [ABSTRACT FROM AUTHOR]

The Egg Safety Action Plan released in 1999 raised many questions concerning egg temperature used in the risk assessment model. Therefore, a national study by researchers in California, Connecticut, Georgia, Iowa, Illinois, North Carolina, Pennsylvania, and Texas was initiated to determine the internal and external temperature sequence of eggs from oviposition through distribution. Researchers gathered data from commercial egg production, processing, and distribution facilities. The experimental design was a mixed model with random effects for season and a fixed effect for duration of the transport period (long or short haul). It was determined that processors used refrigerated transport trucks (REFER) as short-term storage (STS) in both the winter and summer. Therefore, this summary of data obtained from REFER also examines the impact of their use as STS. Egg temperature data were recorded for specific loads of eggs during transport to point of resale or distribution to retailers. To standardize data comparisons between loads, they were segregated between long and short hauls. The summer egg temperatures were higher in the STS and during delivery. Egg temperature was not significantly reduced during the STS phase. Egg temperature decreases were less (P < 0.0001) during short delivery hauls 0.6°C than during long hauls 7.8°C. There was a significant season x delivery interaction (P < 0.05) for the change in the temperature differences between the egg and ambient temperature indicated as the cooling potential. This indicated that the ambient temperature during long winter deliveries had the potential to increase egg temperature. The REFER used as STS did not appreciably reduce internal egg temperature. These data suggest that the season of year affects the temperature of eggs during transport. Eggs are appreciably cooled on the truck, during the delivery phase, which was contrary to the original supposition that egg temperatures would remain static during refrigerated transport. These data indicate that refrigerated transport should be a component in future assessments of egg safety. [ABSTRACT FROM AUTHOR]

In the United States, commercial shell eggs are washed and graded before retail. Since passage of the Egg Products Inspection Act in 1971, processing guidelines have been set to ensure that external and internal characteristics are maintained. However, less is known about how commercial processing affects the safety of shell eggs. To identify enteric bacteria entering plants and persisting throughout processing, eggs were collected from 3 US commercial shell egg-processing plants on 3 separate visits. On each plant visit, 12 eggs were collected from each of 12 sites along the processing line: accumulator, prewash rinse, first washer, second washer, sanitizer rinse, dryer, oiler, check detection/scales, 2 egg grader/packer head lanes, rewash belt entrance, and rewash belt exit. Each egg was sampled by a rinse technique, and the rinsate was plated onto violet red bile glucose agar with overlay for the detection and enumeration of Enterobacteriaceae. From each plate, up to 5 colonies were randomly selected and isolated for identification to genus or species by using biochemical tests. Several genera and species were detected at each of the 3 plants. Sites from which the greatest numbers of isolates were identified were those collected from eggs during preprocessing (accumulator, prewash rinse) or from eggs judged as dirty (rewash belt entrance or exit). Sites yielding the smallest number of isolates were those during or at the end of processing. Escherichia coli and Enterobacter spp. were isolated from each of the 9 plant visits. Other genera isolated from at least 1 of the 3 plants included Cedecea, Citrobacter, Erwinia, Hafnia, Klebsiella, Kluyvera, Leclercia, Morganella, Proteus, Providencia, Rahnella, Salmonella, and Serratia. Non-Enterobacteriaceae isolated and identified included Aeromonns, Chryseomonas, Listonella, Pseudomonas, Sphingobacterium, Vibrio, and Xanthomonas. All of the genera and species were recovered less frequently from fully processed eggs than from unwashed eggs, indicating that shell eggs are less contaminated with bacteria as a result of commercial washing procedures. [ABSTRACT FROM AUTHOR]

The Egg Safety Action Plan released in 1999 raised questions concerning egg temperature used in the risk assessment model. Therefore, a national study was initiated to determine the internal and external temperature sequence of eggs from oviposition through distribution. Researchers gathered data from commercial egg production, shell egg processing, and distribution facilities. The experimental design was a mixed model with 2 random effects for season and geographic region and a fixed effect for operation type (inline or offline). For this report, internal and external egg temperature data were recorded at specific points during shell egg processing in the winter and summer months. In addition, internal egg temperatures were recorded in pre- and postshell egg processing cooler areas. There was a significant season x geographic region interaction (P < 0.05) for both surface and internal temperatures. Egg temperatures were lower in the winter vs. summer, but eggs gained in temperature from the accumulator to the postshell egg processing cooler. During shell egg processing, summer egg surface and internal temperatures were greater (P < 0.05) than during the winter. When examining the effect of shell egg processing time and conditions, it was found that 2.4 and 3.8°C were added to egg surface temperatures, and 3.3 and 6.0°C were added to internal temperatures in the summer and winter, respectively. Internal egg temperatures were higher (P < 0.05) in the preshell egg processing cooler area during the summer vs. winter, and internal egg temperatures were higher (P < 0.05) in the summer when eggs were ¾ cool (temperature change required to meet USDA-Agricultural Marketing Service storage regulation of 7.2°C) in the postshell egg processing area. However, the cooling rate was not different (P > 0.05) for eggs in the postshell egg processing cooler area in the summer vs. winter. Therefore, these data suggest that season of year and geographic location can affect the temperature of eggs during shell egg processing and should be a component in future assessments of egg safety. [ABSTRACT FROM AUTHOR]

During Egg Safety Action Plan hearings in Washington, DC, many questions were raised concerning the egg temperature (T) used in the risk assessment model. Therefore, a national study was initiated to determine the T of eggs from oviposition through distribution. In part 1; researchers gathered data on internal and surface egg T from commercial egg production facilities. An infrared thermometer was used to rapidly measure surface T, and internal T was determined by probing individual eggs. The main effects were geographic region (state) and season evaluated in a factorial design. Egg T data were recorded in the production facilities in standardized comparisons. Regression analysis (P < 0.0001) showed that the R2 (0.952) between infrared egg surface T and internal T was very high, and validated further use of the infrared thermometer. Hen house egg surface and internal T were significantly influenced by state, sea- son, and the state x season interaction. Mean hen house egg surface T was 27.3 and 23.8°C for summer and winter, respectively, with 29.2 and 26.2°C for egg internal T (P < 0.0001). Hen house eggs from California had the lowest surface and internal T in winter among all the states (P < 0.0001), whereas the highest egg surface T were recorded during summer in North Carolina, Georgia, and Texas, and the highest internal T were recorded from Texas and Georgia. Cooling of warm eggs following oviposition was significantly influenced by season, state, and their interaction. Egg internal T when 3/4 cool was higher in summer vs. winter and higher in North Carolina and Pennsylvania compared with Iowa. The time required to 3/4 cool eggs was greater in winter than summer and greater in Iowa than in other states. These findings showed seasonal and state impacts on ambient T in the hen house that ultimately influenced egg surface and internal T. More important, they showed opportunities to influence cooling rate to improve internal and microbial egg quality. [ABSTRACT FROM AUTHOR]

This article reports on investigating the possibility of non-destructively predicting basic quality parameters of shell eggs using an open-ended coaxial probe dielectric measurement technique. The studied parameters include yolk index, thick albumen height, and Haugh unit as well as air cell size as a function of storage duration at room temperature. The probe was connected to an impedance analyzer from which the dielectric spectra (dielectric constant and loss factor) were collected using a data logger and analyzed by means of partial least squares (PLS) analysis. The tests were carried out in the 10 to 1800 MHz frequency band on shell eggs stored for 1, 2, 4, 8 and 15 days at 22 °C, positioning the probe in three different points on the shell eggs. For storage duration, the results showed R² values up to 0.985 and 0.980 in cross-validation and test-set validation, respectively, while the R² for the air cell height was up to 0.927 and 0.921, respectively. Yolk index, thick albumen height, and Haugh unit were also predicted with R² values ranging from 0.526 to O. 728 (test-set validation). No substantial differences in prediction power emerged by using the dielectric constant, loss factor spectra, or position of the probe on the shell egg. The best frequency band for prediction was from 10 to 700 MHz. [ABSTRACT FROM AUTHOR]

Shell eggs were irradiated and the physicochemical, and functional properties of egg yolk and white were determined. The color of egg yolk was not affected, but the viscosity of egg white was dramatically lowered and became watery by irradiation. The foam capacity and foam stability of egg white were significantly decreased due to protein oxidation by irradiation. However, the texture characteristics of egg white were not changed by irradiation, indicating that irradiation may not alter the thermal characteristics of egg white proteins. Sulfur volatiles were generated by irradiation but disappeared during storage under aerobic conditions. Because egg white became watery, irradiation may not be advisable for table eggs but may be useful for pasteurizing liquid egg white or liquid whole egg without significant deterioration of their quality and functionality. In particular, the dramatic decrease in the viscosity of egg white by irradiation will improve flow of liquid egg white or liquid whole egg, which could be highly useful for egg processing. [ABSTRACT FROM AUTHOR]

Salmonella is a zoonotic pathogen commonly transmitted through food. External disinfection of shell eggs is of crucial importance to health in reducing egg-borne salmonellosis, since Salmonella on the shells can be easily transmitted to other food products or infect food handlers. A new thermal treatment was developed for the inactivation of Salmonella enterica on shell eggs. Steam is applied to the eggs while they move through a Thermal Trap (TT)- a partially enclosed chamber filled with steam. Following parameter optimization, a short treatment of a few seconds in a TT prototype completely inactivated Salmonella (>7.8 log CFU reduction) on artificially-inoculated fresh shell eggs. The treatment had no adverse effects on Haugh units, albumen and yolk pH, and albumen whip. The technology is efficient in terms of energy and operation and may provide a feasible solution for shell egg external disinfection. • Shell eggs were treated for external disinfection. • A new method for efficient thermal treatment was applied. • Complete eradication of Salmonella was achieved by seconds of exposure to steam. • No adverse effects on egg quality were found. [ABSTRACT FROM AUTHOR]

Hydrocarbons produced by γ-radiation of shell eggs were analyzed to determine how irradiation affects their production. Shell eggs were nonirradiated or irradiated at 0.5, 1, and 3 kGy and the stored at 5°C for 8 wk or at 30°C for 10 d. Hydrocarbons were determined by a sequential procedure of lipid extraction by hexane, Florisil column chromatography, and gas chromatography. Hydrocarbons C15:0, C14:1, C17:0, C16:1, C17:1, C16:2, C17:2, and C16:3 were detected in shell eggs irradiated at 0.5 kGy or higher, but not in nonirradiated ones except C15:0 and C17:0. Storage of nonirradiated or irradiated eggs had little effect on detection levels of hydrocarbons. The detection levels in all the samples irradiated at 1 and 3 kGy were in the order of C16:2+C17:1, C15:0+C14:1, C17:2+C16:3, and C17:0+C16:1 from the highest to the lowest. [ABSTRACT FROM AUTHOR]

This study investigated the bactericidal effect of low-energy X-ray on mono-culture biofilms of Salmonella Enteritidis and Pseudomonas fluorescens biofilm as well as co-culture biofilms of S. Enteritidis and P. fluorescens at the ratio of 1:1 and 1:100 (S. Enteritidis: P. fluorescens) on shell eggs. The results showed that the low-energy X-ray irradiation could effectively inactivate the mono-culture biofilm cells of S. Enteritidis and P. fluorescens with the t R values of 63.19 Gy and 66.53 Gy, respectively. The low-energy X-ray irradiation could also effectively inactivate co-culture biofilm cells with t R values of 80.03 Gy and 47.97 Gy for S. Enteritidis biofilm cells in the 1:1 and 1:100 ratios of co-culture, respectively, and 61.87 Gy and 30.16 Gy for P. fluorescens biofilm cells in the two ratios of co-co-culture, respectively. Apart from inactivating biofilm cells, extracellular polysaccharide (EPS) was markedly reduced at increasing dosage of irradiation. Based on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and texture profile analysis (TPA) results, egg white proteins and the puncture force of eggshell remained unchanged after the irradiation at up to 225 Gy. No 2-alkylcyclobutanones (2-ACBs) were detected in the irradiated eggs. These findings demonstrated that low-energy X-ray has potential as an effective method to inactivate the mono- and co-culture biofilms of S. Enteritidis and P. fluorescens on shell eggs. • Low energy X-ray showed high sterilization efficacy on egg shell. • Mono/co-culture S. Enteritidis biofilm cells were inactivated by 5 log at 175–225 Gy. • Low-energy X-ray caused destruction of extracellular polysaccharide. • No 2-alkylcyclobutanones (2-ACBs) were detected in irradiated egg. • Irradiation did not change egg white proteins and egg shell puncture force. [ABSTRACT FROM AUTHOR]

The current approaches remain insufficient for measuring chicken egg spoilage or present analytical limitations. This study aimed to complement the existing analyses and identify novel markers using liquid chromatography-high resolution mass spectrometry-based foodomics strategies. In the discovery set, comparative untargeted metabolomics was utilized to identify marker candidates in microbially inoculated chicken eggs. Markers were annotated by spectral matching with authentic standards, experimental libraries, or in silico fragmentation. In the validation set, targeted metabolomics was employed to verify the markers in stored chicken eggs from five farms. Statistical differences at a p -value < 0.001 revealed increases in lactic and 3-hydroxybutyric acids and decreases in phosphocholine, LPE(O-18:1), LPC(16:0), and LPC(18:0) in stored eggs. Receiver operating characteristic curve analysis of the six combined markers yielded an AUC of 0.956 and a sensitivity and specificity of ∼90%. Four phospholipids were highlighted as a novel class of spoilage markers. Our findings may contribute to further industrial implementation, benefiting the quality assurance and food safety of poultry egg production.

The objective of this work was to computationally investigate radio frequency (RF) heating rate and uniformity of shell egg as affected by orientation and rotation. To do this, a multiphysics model was developed using COMSOL to simulate RF heating of a vertically oriented non-rotating shell egg. This model was experimentally validated against temperature measurements taken at three different internal locations within the egg. Simulations were then performed using the validated model with both non-rotating and rotating egg for different orientations (vertical and horizontal). Rotation of egg was incorporated into the model by rotating the RF system around the stationary egg instead of rotating the egg. Temperature-dependent material properties of the yolk, albumen and shell within a temperature range of 20 to 70 °C were used in the model. Simulated temperature uniformity index (STUI) values were calculated to evaluate the effect of orientation and rotation on heating uniformity. The results showed that heating was more uniform when shell egg was oriented horizontally rather than vertically. However, rotation did not further improve heating uniformity of the horizontally-oriented egg. Although heating uniformity was improved when the vertically-oriented egg was rotated, concentrated heating around the air cell could not be avoided. • Radio frequency heating uniformity of vertically-oriented shell egg was highly non-uniform, even when it was rotated. • Shell egg heated much more uniformly, but more slowly, in the horizontal orientation. • Rotation did not improve heating uniformity of the horizontally-oriented shell egg placed in the middle of the electrodes. • A rapid and relatively uniform heating may be achieved if shell egg is horizontally oriented and rotated near the electrodes. [ABSTRACT FROM AUTHOR]

Egg is a regularly consumed food item. Currently, chlorinated water washing is the most common practice used to disinfect eggs, but this process has a negative environmental impact. A new physical technique, plasma-activated water (PAW), has been demonstrated to possess effective antibacterial activities without long-term chemical residue. In this study, air PAW was used to inactivate Salmonella enterica serovar Enteritidis on shell eggs. Different combinations of activation parameters, including water sources (reverse osmotic (RO) water, tap water), power (40 W, 50 W, 60 W) and activation time (10 min, 20 min, 30 min), were evaluated. The oxidation–reduction potential (ORP) and pH values of each combination were measured, and their antibacterial activity was tested in a bacterial suspension. Higher antibacterial activities, higher ORP values, and lower pH values were obtained with higher power, longer activation time, and lower water hardness. The antibacterial activities of PAW decreased rapidly by increasing the storage time both at room and refrigeration temperatures. Afterwards, RO water was pre-activated for 20 min at 60 W, and then the eggs inoculated with S. enteritidis were placed into PAW for 30 s, 60 s, 90 s, or 120 s with a plasma on-site treatment in the water. More than a 4 log reduction was obtained with 60-s and 120-s treatments. The results showed that the freshness indexes of the eggs treated with PAW were similar to those of the untreated controls and better than those of the eggs treated with commercial processes. In addition, observation under a scanning electron microscope also showed less surface damage of the cuticle on the PAW-treated eggs than on the commercially treated eggs. The results of this study indicate that PAW could be an effective antibacterial agent with less damage to the freshness of shell eggs than commercial methods. [ABSTRACT FROM AUTHOR]

The current study was conducted to evaluate the ability to recover Salmonella from shell egg contents by culture methods. A total of 4,000 eggs were obtained from a grading and packing center located in the Gyeonggi Province of South Korea, and 200 samples were created by pooling 20 broken eggs. The pooled samples were held at room temperature for 4 d before a 25-mL aliquot of each pool was added to 225 mL of modified trypticase soy broth (mTSB) and incubated at 35°C for 24 ± 2 h. A loopful of the culture was streaked onto chromogenic Druggan-Forsythe-Iversen (DFI) agar and incubated at 36 ± 1°C for 18-24 h. In addition, 1 mL and/or 0.1 mL of the mTSB cultures were added to 10 mL of Muller-Kauffmann tetrathionate with novobiocin (MKTTn) or Rappaport-Vassiliadis (RV) broth, and they were incubated for 24 ± 2 h at 35 ± 2°C or 42 ± 0.2°C, respectively. A loopful from these cultures was streaked onto Brilliant Green (BG), xylose lysine deoxycholate (XLD), and bismuth sulfite (BS) agar plates, respectively. Directly streaking onto DFI agar revealed the presence of Salmonella in 14 out of the 200 pooled samples (7%); whereas the combination of RV medium and BG, XLD, and BS agar detected the pathogen in only 9 (4.5%), 7 (3.5%), and 3 (1.5%) of the pooled samples, respectively. When MKTTn broth was used, Salmonella was detected in 7 (3.5%), 2 (1%), and 0 (0%) of the samples when streaked onto BG, XLD, and BS agar, respectively. The results indicate that direct plating onto DFI agar without enrichment was the most suitable among the methods evaluated in this study for detecting Salmonella in raw shell egg contents with a low microbial load.