Consumption of beef sandwiches in the United States and contributions to intake of energy and select nutrients.

Introduction: Sandwiches are commonly consumed in the United States. This study summarizes contributions of beef sandwiches to energy and select nutrient intakes. Methods: Beef sandwiches were categorized as beef burger sandwiches (hamburgers or cheeseburgers) and non-burger beef sandwiches. Per capita and per user consumption of beef sandwiches (total and by type) and contributions to total nutrient intakes from beef and non-beef sandwich components were estimated for the population ages ≥2 years (n = 15,984) participating in WWEIA/NHANES, 2013-2016. Results: On any given day, 21.4% of the population consumed a beef sandwich. Among all Americans, beef sandwiches provided 6.3% of mean energy intake and accounted for approximately 10% of the population's mean intake of vitamin B12 and saturated fat, 9% of protein and sodium, 7% of iron, 6% of choline, and 5% of potassium. Among beef sandwich consumers, beef sandwiches accounted for 26.2% of mean energy intake on a day of consumption. The beef component of sandwiches accounted for the majority of vitamin B12, choline, and protein, non-beef components accounted for the majority of sodium, iron, and potassium, and beef and non-beef components made similar contributions to saturated fat. Hamburgers provided consumers the lowest energy, sodium, and saturated fat intake, while non-burger sandwiches provided the highest intake of these nutrients. Discussion: Beef sandwiches are an important source of energy, protein, vitamin B12, iron, and choline, and like other sandwiches, are also a source of sodium and saturated fat. Americans could enhance nutrient contributions from sandwiches by selecting lean meat and limiting use of saturated fat- or sodium-rich non-beef components.

Clarithromycin-, and metronidazole-resistant Helicobacter pylori isolated from raw and ready-to-eat meat in Mansoura, Egypt.

Helicobacter pylori (H. pylori), classified as a class-I carcinogen, is one of the leading medical pathogens of global concern associated mainly with the development of gastric adenocarcinomas and gastric mucosa-associated lymphoid tissue lymphomas; nevertheless, its prevalence in food especially meat and meat products is not fully covered. Additionally, the resistance of H. pylori towards clarithromycin is increasing worldwide and consider the leading cause of H. pylori treatment failure. Thus, the present study was designed to determine the prevalence, molecular characterization, and antimicrobial resistance profiles of clarithromycin-, and metronidazole-resistant H. pylori isolated from raw and ready-to-eat meat samples retailed in Mansoura city, Egypt. Among the 250 samples tested, H. pylori were molecularly confirmed in 40.8 % (49/120) of raw meat products and in 29.2 % (38/130) of ready-to-eat meat products. Precisely, 53.3 % (32/60), 56.7 % (17/30), 40 % (8/20), 55 % (11/20), 60 % (12/20), 13.3 % (4/30), and 15 % (3/20) of raw ground beef, beef burger, beef burger sandwiches, beef shawarma sandwiches, beef kofta sandwiches, beef luncheon, and beef sausage sandwiches, respectively were positive for H. pylori. Of the 204 biochemically-identified H. pylori isolates, 53.9 % (110/204) were molecularly confirmed by PCR through the detection of glmM, cagA, or vacA genes, which were detected at an incidence of 95.5 % (105/110), 77.3 % (85/110), and 20.9 % (23/110) among the isolates, respectively. The antimicrobial sensitivity testing revealed that all of the 110 (100 %) molecularly-confirmed H. pylori isolates were multidrug-resistant (MDR; resistant to four or more antibiotics). Interestingly, 100 % and 61.8 % of H. pylori isolated from raw and ready-to-eat meat were resistant to metronidazole and clarithromycin, respectively which consider alarming results as metronidazole and clarithromycin are the mainstay antibiotics in the treatment of H. pylori infections. Additionally, 94.5 %, 94.5 %, 24.5 %, 23.6 %, and 13.6 % of isolates were resistant to vancomycin, sulphamethoxazole-trimethoprim, imipenem, levofloxacin, and nitrofurantoin, respectively. The widespread contamination of examined raw and ready-to-eat meat product samples with MDR H. pylori isolates could constitute a tremendous public health hazard. Further studies concerning the prevalence and possible methods of elimination of H. pylori in different food categories distributed in the various provinces in Egypt as well as in other countries is required for a better understanding the H. pylori as an emerging foodborne pathogen.

Cyclopentadienyl Complexes of the Alkaline Earths in Light of the Periodic Trends.

The electron-rich cyclopentadienyl and the analogous indenyl and fluorenyl ligands (collectively denoted here as Cp') have been impactful in stabilizing electron-deficient metal centers including the highly electropositive alkaline earths. Being in the s-block, the group 2 metals follow a major periodic variation in their atomic and ionic properties which is reflected in those Cp' compounds. This article presents an overview of this class of compounds for all the five metals from beryllium to barium (radium is excluded for its radioactivity), highlighting their systematic variation.

Characterization of virulence factors of Salmonella isolated from human stools and street food in urban areas of Burkina Faso.

BACKGROUND: This study was undertaken to identify and functionally characterize virulence genes from Salmonella isolates in street food and stool cultures. From February 2017 to May 2018, clinical and food Salmonella strains were isolated in three regions in Burkina Faso. Salmonella was serotyped according to the White-Kauffmann-Le Minor method, and polymerase chain reaction (PCR) was used to detec invA, spvR, spvC, fimA and stn virulence genes commonly associated with salmonellosis in Sub-Saharan Africa. RESULTS: A total of 106 Salmonella isolates (77 human stools; 14 sandwiches) was analyzed using a serological identification with an O-group test reagent. The presence of Salmonella was confirmed in 86% (91/106) of the samples were reactive (OMA-positive/OMB-positive). Salmonella serogroup O:4,5 was the most common serogroup detected (40%; 36/91). Salmonella Enteritidis and Typhimurium represented 5.5% (5/91) and 3.3% (3/91), respectively and were identified only from clinical isolates. Furthermore, 14 serotypes of Salmonella (12/91 human strains and 2/15 sandwich strains) were evocative of Kentucky/Bargny serotype. For the genetic profile, 66% (70/106) of the Salmonella had invA and stn genes; 77.4% (82/106) had the fimA gene. The spvR gene was found in 36.8% (39/106) of the isolates while 48.1% (51/106) had the spvC gene. Among the identified Salmonella Enteritidis and Salmonella Typhimurium isolated from stools, the virulence genes detected were invA (3/5) versus (2/3), fimA (4/5) versus (3/3), stn (3/5) versus (2/3), spvR (4/5) versus (2/3) and spvC (3/5) versus (2/3), respectively. CONCLUSION: This study reports the prevalence of Salmonella serotypes and virulence genes in clinical isolates and in street foods. It shows that food could be a significant source of Salmonella transmission to humans. Our results could help decision-making by the Burkina Faso health authority in the fight against street food-related diseases, in particular by training restaurateurs in food hygiene.

Predictive modeling and probabilistic risk assessment of Clostridium perfringens in hamburgers and sandwiches.

This study aimed to develop a mathematical model for the survival of Clostridium perfringens in hamburgers and sandwiches and to evaluate their microbial risk. The primary model was developed in hamburgers using 4 strains of C. perfringens at 5, 10, 15, 25 and 37 °C, and the kinetic parameters of the primary model were fitted well with the Weibull model (R 2 ≥ 0.95). The secondary model was developed and validated in hamburgers and sandwiches using the Davey model, which was evaluated by B f , A f , and RMSE values within the acceptable range. A probabilistic risk model was developed and simulated using @Risk program to estimate the probability of infection (P inf ) of C. perfringens based on the data on prevalence (n = 100), time, temperature, and consumption of hamburgers and sandwiches (150.00 ± 20.96 g). Based on the simulation model, the mean C. perfringens exposure dose was 0.00976 CFU/g, and the estimated mean P inf was 1.78 × 10-13, which was very low in comparison with the current available data. The proposed model and the result can thus be useful to establish risk management options and microbial criteria for C. perfringens contamination in hamburgers and sandwiches. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10068-021-01000-z.

Epidemiological investigations identified an outbreak of Shiga toxin-producing Escherichia coli serotype O26:H11 associated with pre-packed sandwiches.

In October 2019, public health surveillance systems in Scotland identified an increase in the number of reported infections of Shiga toxin-producing Escherichia coli (STEC) O26:H11 involving bloody diarrhoea. Ultimately, across the United Kingdom (UK) 32 cases of STEC O26:H11 stx1a were identified, with the median age of 27 years and 64% were male; six cases were hospitalised. Among food exposures there was an association with consuming pre-packed sandwiches purchased at outlets belonging to a national food chain franchise (food outlet A) [odds ratio (OR) = 183.89, P < 0.001]. The common ingredient identified as a component of the majority of the sandwiches sold at food outlet A was a mixed salad of Apollo and Iceberg lettuce and spinach leaves. Microbiological testing of food and environmental samples were negative for STEC O26:H11, although STEC O36:H19 was isolated from a mixed salad sample taken from premises owned by food outlet A. Contamination of fresh produce is often due to a transient event and detection of the aetiological agent in food that has a short-shelf life is challenging. Robust, statistically significant epidemiological analysis should be sufficient evidence to direct timely and targeted on-farm investigations. A shift in focus from testing the microbiological quality of the produce to investigating the processes and practices through the supply chain and sampling the farm environment is recommended.

Listeriosis associated with pre-prepared sandwich consumption in hospital in England, 2017.

A case of listeriosis occurred in a hospitalised patient in England in July 2017. Analysis by whole genome sequencing of the Listeria monocytogenes from the patient's blood culture was identified as clonal complex (CC) 121. This culture was indistinguishable to isolates from sandwiches, salads and the maufacturing environment of Company X which supplied these products widely to the National Health Service. Whilst an inpatient, the case was served sandwiches produced by this company on 12 occasions. No other cases infected by this type were detected in the UK between 2016 and 2020. Between 2016 and 2020, more than 3000 samples of food, food ingredients and environmental swabs from this company were tested. Listeria monocytogenes contamination rates declined after July 2017 from 31% to 0.3% for salads and 3% to 0% for sandwiches. A monophyletic group of 127 L. monocytogenes CC121 isolates was recovered during 2016-2019 and was used to estimate the time of the most recent common ancestor as 2014 (95% CI of between 2012 and 2016). These results represent persistent contamination of equipment, food contact surfaces and foods at a food manufacturer by a single L. monocytogenes strain. Colonisation and persistent contamination of food and production environments are risks for public health.

Photograph Based Evaluation of Consumer Expectation on Healthiness, Fullness, and Acceptance of Sandwiches as Convenience Food.

Sandwiches are the most common "casual-food" consumed by all age groups in Spain. Due to the importance of visual appearance to promote unplanned or impulse buying, foodservice and hospitality companies focus on improving the visual impression of their food menus to create an expectation that satisfies both sensory and hedonic consumer experiences. To provide a list of attributes about the visual appearance of sandwiches, 25 students were recruited from a university and were invited to participate in two nominal group technique (NGT) sessions. To understand whether a sandwiches' appearance can influence the expectation of consumers, 259 participants completed an online survey specially designed from the results of the NGT sessions. Data were analyzed using conjoint, internal preference mapping and cluster analysis; the interaction effect by gender was also studied. The conjoint results indicate that visual perception about the filling (vegetal or pork based) plays the most key role overall in consumer expectation. When consumers choose vegetables as the filling, the consumers' perceived sandwiches as healthier, but the pork filling was perceived as more attractive and satiating. Interaction effect by gender was observed in filling when females perceived pork filling as less healthy than vegetable. By acceptance, consumers were segmented into three groups. The first cluster (n = 80) selected the pork filling. The smaller group (cluster 3, n = 36) prioritized the vegetal filling, and the most numerous cluster 2 (n = 140) liked sandwiches with multigrain bread. These results may help companies to build tailor-made marketing strategies to satisfy consumer segments.

Multidrug-, methicillin-, and vancomycin-resistant Staphylococcus aureus isolated from ready-to-eat meat sandwiches: An ongoing food and public health concern.

Methicillin-resistant S. aureus (MRSA) and their antimicrobial resistance pose exacerbating global health threats and endangering everyone. Thus, the prevalence, molecular characterization of virulence genes, and antimicrobial resistance patterns of strains isolated from 225 beef burger and hot dog sandwiches vended in Mansoura city, Egypt were determined. 83.1% of the sandwiches tested were contaminated with coagulase-positive S. aureus, with a mean count of 4 × 103 CFU/g. Genes encoding mecA, α-hemolysin, staphylococcal enterotoxins, and toxic shock syndrome toxin-1 were detected in 22.6%, 96.3%, 61.1%, and 0% of the strains isolated, respectively. Of the 190 coagulase-positive strains, 43 (22.6%) were confirmed as MRSA. Among them, 4 strains (2.1%) were vancomycin-resistant S. aureus (VRSA) and resistant to all antimicrobials tested. Interestingly, all isolates were resistant to at least one of the antimicrobials tested, with 75.2% being multi-drug resistant (MDR) and an average multiple antimicrobial resistance (MAR) index of 0.503. Not less important, 100%, 96.3%, 90.5%, 79.5%, 73.7%, 62.6%, and 48.9% of isolates were resistant to Kanamycin, Nalidixic acid, Cefotaxime, Sulphamethoxazole-Trimethoprim, Penicillin G, Tetracycline, and Cephalothin, respectively. The potential hazard of MDR-, MRSA-, and VRSA-contaminated sandwiches may be an indication of the presence of what is more dangerous. Hence, strict hygienic measures and good standards of food handler's personal hygiene to prevent transmission of these pathogens to consumers are imperative.

Assessing microbiological quality of ready-to-eat prepacked sandwiches, in Crete, Greece.

The microbiological quality of pre-packed sandwiches, prepared by a company which had implemented the Hazard Analysis Critical Control Points system, was assessed at retail level, in Crete, Greece. Totally, we analyzed 225 sandwiches (S1: ham, cheese; S2: ham, cheese, tomato; S3: tuna salad), for specific pathogens (Listeria monogytenes, Salmonella spp, Staphylococcus aureus) and hygiene indicators (Escherichia coli, Enterobacteriaceae, Aerobic Colony Count-ACC). Pathogens were not detected. The E. coli numbers enumerated in day 0 (factory level) were found within acceptable levels < 100 cfu/g; limited samples had unsatisfactory values at the 3rd day of retailing storage (7%, 7%, and 27% > 100 cfu/g for S1, S2, and S3, respectively), which were further increased at the 7th day (20%, 33% and 53% > 100 cfu/g for S1, S2, and S3, respectively). The Enterobacteriaceae numbers mean log CFU/g were in the satisfactory or acceptable category with an increase in the range of 19.5-49.5% at the 7th day, nevertheless never exceeded the borderline of 4 log CFU/g. All ACC values were satisfactory or acceptable as no value higher than 7 log CFU/g was recorded. Overall there was a difference between the three sandwiches types, with S2 and S3, exhibiting higher levels than S1, possibly due to the extra ingredients. A number of corrective actions can be applied, as i.e. revision of cooking-chilling times, sanitizing procedures, staff hygiene practices and training etc.

Type of Sandwich Consumption Within a US Dietary Pattern Can Be Associated with Better Nutrient Intakes and Overall Diet Quality: A Modeling Study Using Data from NHANES 2013-2014.

BACKGROUND: Previous research in adults has reported an association between sandwich consumers and increased daily energy, total fat, and sodium intakes and decreased dietary fiber intake. Additionally, sandwich consumers had a lower diet quality, as compared to non-sandwich consumers. However, the research failed to differentiate between the types of sandwiches consumed. OBJECTIVES: The purpose of this study was to model different sandwiches, using both whole-grain bread (WGB), enriched-grain bread (EGB), and soft taco tortillas, to examine associations with energy (kcal), nutrient intakes, and diet quality, in comparison to the typically consumed sandwich (control). METHODS: Data from the NHANES 2013-2014 was used to complete the analyses in adults ≥19 years old, and USDA food composites were used to create 5 sandwich types, using WGB, EGB, or soft corn tortillas. RESULTS: In the modeling analysis, adults consuming the soft corn tortilla taco had lower energy, as compared to those eating the typical sandwich. Total fat intakes were lower in the WGB and EGB grilled chicken/cheese/vegetable sandwiches and in the soft taco tortilla, in comparison to the control sandwich. Sodium intakes were lower in the WGB and EGB grilled chicken/cheese/vegetable sandwiches and in the soft taco tortilla, in comparison to the typical sandwich consumed. All WGB sandwich models and the soft taco tortilla had greater daily dietary fiber intakes, in comparison to the control sandwich. WGB, EGB, and tortilla sandwiches were also associated with greater intakes of shortfall nutrients. All sandwich models, except EGB with meat/cheese/vegetables, had higher diet qualities, in comparison to the control. CONCLUSIONS: The current data support the inclusion of certain WGB and EGB sandwiches/tortillas, within recommended dietary patterns, in American adults, and suggest that ingredients within a sandwich, rather than the just the bread component, can be an important contributor to overall nutrient intakes and nutrients to limit in the diet.

NDE Detection Techniques and Characterization of Aluminum Wires Embedded in Honeycomb Sandwich Composite Panels Using Terahertz Waves.

For many years, scientists have been aware of the importance of terahertz waves (T-rays), which have now emerged as an NDE (nondestructive evaluation) technique for certain ranges of the electronic spectrum. The present study deals with T-ray scanning techniques of honeycomb sandwich composite panels with a carbon-fiber-reinforced plastic (CFRP) skin as well as the refractive index (n), and the electrical conductivity (α) of glass fiber-reinforced plastic (GFRP) composites. For this experiment, the degree of penetration to FRP composites is investigated for the THz transmitted power based on the angle in the electric field (E-field) direction vs. the direction of the unidirectional carbon fibers. Also, when CFRP skin honeycomb sandwich panels are manufactured for use in aerospace applications, aluminum wires are twisted together into the one-sided surface of the honeycomb sandwich panels to protect against thunderstorms. The aluminum wires are partly visible because they are embedded in the CFRP skin on the honeycomb sandwich panels. After finishing work with a paintjob, the wires become invisible. Thus, detecting the aluminum wires is a key issue for product monitoring. Based on a simple resistor model, an optimal scanning method is proposed to determine the preferred scan orientation on the baseline of the E-field in the direction of fibers to evaluate the level of transmission of T-rays according to the frequency bandwidth. Thus, the combination of angles required to detect the aluminum wires embedded with carbon fibers on the surface of the composite panels can be determined.

Buenas prácticas de manufactura y microorganismos indicadores en sándwiches de verdura expendidos en el mercado central de abasto de Asunción, Paraguay (2014) / Good manufacturing practices and indicator microorganisms in vegetable sandwiches expended at the central supply market in Asunción, Paraguay (2014)

El objetivo de este estudio descriptivo y transversal fue describir la presencia de microorganismos indicadores y las BPM en los locales que producen sándwiches de verdura en el Mercado Central de Abasto de Asunción (MCAA) en el 2014. Se eligieron sándwiches de verduras debido a la materia prima cruda y mayonesa, a que no sufren tratamiento térmico y son de consumo masivo. Se elaboró una lista de verificación para las BPM según la FAO/OMS. Se estudiaron 20 muestras en 10 locales(2/local) para Recuento de Aerobios Mesófilos (RAM), coliformes totales, E. coli y S. aureus. El límite microbiológico fue dado por la Norma Sanitaria del Ministerio de Salud de Perú y la técnica utilizada fue el Recuento en Placa, utilizando placas de 3M PETRIFILM.El 90% de los 10 localestenía limpieza adecuada,todos refirieron lavadode las verduras previa utilización, para lo cual usaban agua de canilla (90%)o agua reutilizada (10%). El 70% de los manipuladores refirió lavadode manos previa manipulación y 90% después.El 80% de los locales refirió utilizar mayonesa comercial y el 30% la mantenía a temperatura ambiente durante todo el día.El 20% de los locales ofrecíaal día siguiente los sándwiches no vendidos. El 95% (19 de 20)de las muestras se considera microbiológicamente como “No Aptas” para el consumo, el 70% presentó recuentos mayores para RAM, 85% para coliformes, 30% para E. coli y 75% para S. aureus. Estos productos pueden ser considerados de riesgo para el consumo humano.

The objective of this cross-sectional descriptive study was to evaluate the presence of indicator microorganismsand to describe the Good Manufacturing Practices (GMP) in places producing vegetable sandwiches of the Central Supply Market of Asunción (MCAAfor its name in SpanishMercado Central de Abasto de Asunción)in 2014. Vegetable sandwiches were chosen for being of high risk, as they use raw materials and mayonnaise, they do not undergo heat treatment and are of massive consumption.For GMP, a checklist was prepared according to FAO / WHO. Twenty samples in 10 shops (2 samples per shop) were studied for Mesophilic Aerobic Count, total coliform counts, E. coli and S. aureus. Ninety percent of the 10 stores had adequate cleaning. Hundred percent claimed to wash the raw material (vegetables) before being used, 90% used tap water and 10% washed them with reused water. Seventy percent of the cooks washed their hands before preparing the sandwiches and 90% afterwards. Eighty percent of the stores used commercial mayonnaise and 30% keepthem at room temperature throughout the day. Twenty percent of the stores offered unsold sandwiches the next day.Of the 20 samples, 19 (95%) were considered microbiologically as "Not Apt" for consumption, 70% due to high Counting of Mesophilic Aerobes, 85% coliforms, 30% E. coli and 75% S. aureus. These products can be considered as a risk for human consumption.

Vibration Damping Analysis of Lightweight Structures in Machine Tools.

The dynamic behaviour of a machine tool (MT) directly influences the machining performance. The adoption of lightweight structures may reduce the effects of undesired vibrations and increase the workpiece quality. This paper aims to present and compare a set of hybrid materials that may be excellent candidates to fabricate the MT moving parts. The selected materials have high dynamic characteristics and capacity to dampen mechanical vibrations. In this way, starting from the kinematic model of a milling machine, this study evaluates a number of prototypes made of Al foam sandwiches (AFS), Al corrugated sandwiches (ACS) and composite materials reinforced by carbon fibres (CFRP). These prototypes represented the Z-axis ram of a commercial milling machine. The static and dynamical properties have been analysed by using both finite element (FE) simulations and experimental tests. The obtained results show that the proposed structures may be a valid alternative to the conventional materials of MT moving parts, increasing machining performance. In particular, the AFS prototype highlighted a damping ratio that is 20 times greater than a conventional ram (e.g., steel). Its application is particularly suitable to minimize unwanted oscillations during high-speed finishing operations. The results also show that the CFRP structure guarantees high stiffness with a weight reduced by 48.5%, suggesting effective applications in roughing operations, saving MT energy consumption. The ACS structure has a good trade-off between stiffness and damping and may represent a further alternative, if correctly evaluated.

Listeria Spp. and Listeria Monocytogenes Contamination in Ready-To-Eat Sandwiches Collected from Vending Machines.

Ready-to-eat (RTE) food is characterised by a long shelf-life at refrigerated temperature and can be consumed as such, without any treatment. The aim of the work was to evaluate the presence of Listeria spp. and Listeria monocytogenes in RTEs collected from refrigerated vending machines placed in hospital environment and accessible to the hospitalised patients. In 4 different sampling, 55 RTEs were collected from vending machines of six hospitals located in different areas of Sardinia region. All the samples were characterised by similar manufacturing process, such as the use of modified atmosphere packaging and belonged to 5 different producers. Listeria spp. was not countable using the enumeration method in all of the analysed samples. Using the detection method, Listeria spp. was recovered from 9 sandwich samples. Interestingly, 3 of these samples (5.5%) made by the manufacturer, were positive for L. monocytogenes contamination. The risk related to the L. monocytogenes presence in RTEs proportionally increases when food is introduced in susceptible environments, such as hospitals and consumed by susceptible people. Although the RTEs analysed showed values that complied with the European microbiological criteria for foodstuffs, the availability of these products in a susceptible environment should be carefully checked. Therefore, in order to limit the possible exposition to L. monocytogenes, more information on the risk related to RTE consumption should be provided to the hospitalised patients.

Asymmetric MoS2 /Graphene/Metal Sandwiches: Preparation, Characterization, and Application.

The polarizable organic/water interface is used to construct MoS2 /graphene nanocomposites, and various asymmetrically dual-decorated graphene sandwiches are synthesized. High-resolution transmission electron microscopy and 3D electron tomography confirm their structure. These dual-decorated graphene-based hybrids show excellent hydrogen evolution activity and promising capacitance performance.

Two Outbreaks of Salmonella enteritidis Associated with Monte Cristo Sandwiches.

We report on two outbreaks of Salmonella enteritidis which occurred in 1992; both were associated with Monte Cristo sandwiches. The first outbreak, which occurred in Woods Hole, Massachusetts, was investigated as a case-control study, and involved 74 persons. The second outbreak, investigated as a cohort study, occurred in Brewster, Massachusetts, and involved 32 persons. Monte Cristo sandwiches were strongly implicated in both outbreaks; the odds ratio in the case-control study was 43, and the relative risk in the cohort study was 13. Food-preparation procedures were reviewed and food handlers were educated about safe food-preparation practices. Because of the short grilling time for Monte Cristo sandwiches, (usually several minutes) the eggs used in the preparation may only be partially cooked. As a result, this food should be viewed as high risk for S. enteritidis . Pasteurized eggs should be used to prepare Monte Cristo sandwiches, especially in a commercial setting.