Pasta Salad Research Articles

Validation of the CompactDry "Nissui" BC for Enumeration of Bacillus cereus in a Variety of Foods: AOAC Performance Tested MethodSM 092201.

The CompactDry "Nissui" BC is a ready-to-use dry media sheet using a chromogenic medium with selective agents for the detection and enumeration of Bacillus cereus in products after incubation at 30 ± 1°C for 24 ± 2 h. The CompactDry "Nissui" BC method was validated to achieve AOAC Performance Tested MethodsSM certification. The performance of the CompactDry "Nissui" BC was compared to that of ISO 7932:2004 for 10 matrixes, including panna cotta, double cream, dried baby food, dried vegetable soup mix, seafood sticks, salmon pâté, sliced ham, pork liver pâté, ham and cheese sandwich, and Caesar pasta salad with chicken and bacon. Performance indicators included repeatability, difference of means (DOM), and inclusivity/exclusivity. After log10 transformation of the data, the relative standard deviation of repeatability (RSDr) was ≤9.2% for 28 of the 30 materials (10 matrixes each at three contamination levels) analyzed by the CompactDry "Nissui" BC method and ≤13% for 27 of the 30 matrix/level combinations analyzed by the reference method. Method equivalence was demonstrated in 28 of the 30 matrix/level combinations based on the 90% confidence interval of the DOM being within (-0.5, 0.5). For inclusivity, 47 of 50 strains tested showed typical colonies and confirmed positive. For exclusivity, 28 of 33 strains tested resulted in no growth or were negative, and five were positive. Inclusivity and exclusivity results were similar on the reference method agar. The method was shown to be robust to changes in sample volume, incubation temperature, and incubation time, and data are presented supporting product consistency and 18-month shelf life. The CompactDry "Nissui" BC method is validated for the determination of Bacillus cereus in a variety of matrixes. The CompactDry "Nissui" BC method is equivalent to the ISO 7932:2004 reference method and is suitable for Performance Tested MethodsSM certification for the matrixes tested.

Validation of the CompactDry "Nissui" YMR for Enumeration of Yeasts and Molds in a Variety of Foods: AOAC Performance Tested MethodSM 092002.

The CompactDry "Nissui" YMR is a ready-to-use dry media sheet using a chromogenic medium with selective agents for the detection and enumeration of yeasts and molds in products after incubation at 25 ± 1°C for 3 days. The CompactDry "Nissui" YMR method was validated in order to achieve AOAC Performance Tested MethodsSM certification. The performance of the CompactDry "Nissui" YMR was compared to that of ISO 21527-1:2008 for 10 matrixes including cooked prawns, deli vegetable salad, tuna pâté, fermented yogurt drink, spinach and ricotta quiche, egg custard tarts, fruit and vegetable smoothie, cream cheese, egg salad sandwich, and deli pasta salad. Performance indicators included repeatability, difference of means (DOM), and inclusivity/exclusivity. After log10 transformation of the data, the relative standard deviation of repeatability (RSDr) was <10% for all 30 materials (10 matrixes each at 3 levels) analyzed by the CompactDry "Nissui" YMR method and for 29 of the 30 matrix/level combinations analyzed by the reference method. The DOM ranged from -0.284 (-0.310, -0.257) log10 CFU/g to 0.307 (-0.013, 0.627) log10 CFU/g. Method equivalence was demonstrated in 29 of the 30 matrix/level combinations based on the 90% confidence interval of the DOM being within (-0.5, 0.5). All 51 inclusivity strains showed expected or atypical results, and all 32 exclusivity organisms showed no growth on the medium. The method was shown to be robust to changes in sample volume, incubation temperature, and incubation time, and data are presented supporting product consistency and a 24-month shelf life. The CompactDry "Nissui" YMR method is validated for the determination of yeasts and molds in a variety of matrixes. The CompactDry "Nissui" YMR method is equivalent to the ISO 21527-1:2008 reference method and is suitable for Performance Tested MethodsSM certification for the matrixes tested.

Does labelling a food as ‘light’ vs. ‘filling’ influence intake and sensory-specific satiation?

Although several studies have investigated the influence of nutrition labelling on food intake, the effect of labels indicating a food's satiating power on food intake and sensory-specific satiation (SSS) is poorly understood. We investigated whether providing information about the satiating power of a meal affects intake and SSS. Participants (19 men and 18 women) consumed the same test meal of pasta salad ad libitum on two occasions, once described as ‘light’ and once as ‘filling’. SSS was determined as the change in liking of the flavor and desire to eat the test meal before and after consumption, compared to seven uneaten foods. As hypothesized, intake increased by a mean (±SD) of 31 ± 59 g and 42 ± 81 kcal when the meal was labelled ‘light’ as opposed to ‘filling’ (p < 0.01). After eating, ratings for both liking and desire to eat decreased significantly more for the test meal than for the uneaten control foods (p < 0.001), demonstrating SSS. These relative changes in liking and desire to eat did not differ between the label conditions, despite differences in intake. Furthermore, accounting for amount consumed, the magnitude of SSS did not differ between the label conditions, which suggests that it did not explain the effect of the labels on intake. This study shows that labels indicating the satiating power of a meal can affect intake, warranting caution in the use of such labels on products intended to reduce intake.

3D Phage-based biomolecular filter for effective high throughput capture of Salmonella Typhimurium in liquid streams

Foodborne illnesses caused by pathogens on fresh produce remain one of the most critical food safety problems the world faces. The recalls of pasta salad in 2018 and pre-cut melons in 2019 imply current methods in identifying the source of pathogens and outbreak prevention are inappropriate and time consuming. In this article, a new technology, called the 3D phage-based biomolecular filter, was developed to simultaneously capture and concentrate foodborne pathogens from large volumes of liquid streams (food liquid or wash water streams). The 3D phage-based filter consisted of phage-immobilized magnetoelastic (ME) filter elements, a filter pipe system, and a uniform magnetic field to fix and align the ME filter elements in the 3D filter column. The closely packed ME filter elements display a 3D layered structure which allows for enhanced surface interaction of the immobilized bacteriophage with specific pathogens in the passing liquid streams. As a result, a pathogen capture rate of more than 90% was achieved at a high flow rate of 3 mm/s with 20,000 ME filter elements. The capability of the 3D phage-based filter to capture pathogens in liquid streams at different filter element packing densities was further validated by experiments, finite element analysis and theoretical calculations. The capture rate increases significantly with larger numbers of ME filter elements placed in the testing pipe, and the turbulence flow induced by the 3D stacking of ME filter elements can further improve the capture efficiency. This technology enables rapid capture and analysis of large volume of water in processing fresh fruit and vegetables for the presence of small quantities of pathogens, which will ultimately benefit producers, the food industry, and society with improved food safety and production efficiency.

CompactDry "Nissui" ETC for Enumeration of Enterococci in a Variety of Foods: AOAC Performance Tested MethodSM 111902.

The CompactDry "Nissui" ETC is a ready-to-use dry media sheet using a chromogenic medium with selective agents for the detection and enumeration of Enterococcus spp. After a 20-24 h incubation at 37 ± 1°C, Enterococcus colonies appear blue. The performance of the CompactDry "Nissui" ETC was compared to that of the Nordic Committee on Food Analysis (NMKL) reference method 68, Enterococcus, Determination in Foods and Feeds, for 10 matrixes including cream, custard, lettuce, parsley, pasta salad, frozen ground beef patties, fresh cooked prawns, sandwiches, raw beef, and tuna pate. Performance indicators included repeatability, difference of means (DOM), robustness and inclusivity/exclusivity. For all 30 materials (10 matrixes each inoculated at three levels), the relative standard deviation of repeatability (RSDr) was <10% for both methods. Most materials yielded RSDr <5%, with five materials between 5 and 10% for the CompactDry "Nissui" ETC method and ten materials between 5 and 10% for the NMKL 68 method. The DOM ranged from -0.240 (95% CI-0.363, -0.118) to 0.228 (95% CI 0.041, 0.415) log10 CFU/g, well within the -0.5 to 0.5 log10 CFU/g range generally accepted as microbiologically insignificant. Both the reference method and this method have limitations of the species detected. The CompactDry "Nissui" ETC was validated for the enumeration of Enterococcus species in cream, custard, lettuce, parsley, pasta salad, frozen ground beef patties, fresh cooked prawns, sandwiches, raw beef, and tuna pate.

The effect of selected preservatives on the growth of Listeria monocytogenes in ready-to-eat foods

Our study evaluated the possibility of survival and growth of L. monocytogenes in 9 types of ready-to-eat foods. The evaluation was focused on the effectiveness of selected preservatives, namely sodium benzoate mixed with potassium sorbate (E 211 and E 202) and a commercially available preservative Defence JB. All delicatessen products were stored at 5 or 6 °C. The enumeration of L. monocytogenes was carried out in accordance with the reference ISO method. In most tested products, L. monocytogenes was unable to proliferate and its counts at the end of storage were significantly lower than those at the baseline after the artificial inoculation. This holds true both for samples with preservatives and for those without any preservative. The only exceptions were pasta salad and hard-boiled eggs in mayonnaise, with L. monocytogenes reaching the same (hard-boiled eggs in mayonnaise) or even higher counts (pasta salad) at the end of storage than at the baseline, both in the presence and absence of preservatives. Our results suggest that synergistic effects of intrinsic factors such as pH and aw with low storage temperatures plays a greater role in controlling L. monocytogenes growth than the tested preservatives (sodium benzoate/potassium sorbate and Defence JB).

Characterization of A Staphylococcal Food Poisoning Outbreak in A Workplace Canteen during the Post-Earthquake Reconstruction of Central Italy.

In summer 2017, a foodborne outbreak occurred in Central Italy, involving 26 workers employed in the post-earthquake reconstruction. After eating a meal provided by a catering service, they manifested gastrointestinal symptoms; 23 of them were hospitalized. The retrospective cohort study indicated the pasta salad as the most likely vehicle of poisoning. Foods, environmental samples, and food handlers’ nasal swabs were collected. Bacillus cereus (Bc) and coagulase-positive staphylococci (CPS) including S. aureus, together with their toxins, were the targets of the analysis. CPS, detected in all the leftovers, exceeded 105 CFU/g in the pasta salad, in which we found Staphylococcal Enterotoxins (SEs) (0.033 ng SEA/g; 0.052 ng SED/g). None of the environmental and human swabs showed contamination. We characterized 23 S. aureus from foods. They all belonged to the human biotype, showed the same toxigenic profile (sea, sed, sej, and ser genes), and had the same Pulsed Field Gel Electrophoresis (PFGE) pattern; none of them harbored mecA or mupA genes. We also detected Bc contamination in the pasta salad but none of the isolates harbored the ces gene for the emetic toxin cereulide. The EU Reference Laboratory for CPS confirmed the case as a strong-evidence outbreak caused by the ingestion of SEs produced by a single strain of S. aureus carried by the same human source. This outbreak was successfully investigated despite the emergency situation in which it occurred.

Corrigendum to "The STARTEC Decision Support Tool for Better Tradeoffs between Food Safety, Quality, Nutrition, and Costs in Production of Advanced Ready-to-Eat Foods".

[This corrects the article DOI: 10.1155/2017/6353510.].

The Validation of the Dai Nippon Medi·Ca SA Method for AOAC Research Institute Performance Tested MethodsSM Certification.

A ready-made dry medium method for Staphylococcus aureus count, the Medi·Ca SA method incubated at 35 or 37°C, was compared with the Baird-Parker method (AOAC Official MethodSM 975.55) for 11 food matrices: raw beef, raw ground beef, raw lamb, cooked ham, raw salmon, frozen prawn, fresh chilled pasta, pasteurized milk, natural cheese, cream puff, and potato salad. The mean difference between the two methods at each contamination level for each matrix was <0.5 log10, and the 95% confidence intervals on the mean differences fell within the range of -0.50 to 0.50. Standard deviation of repeatability and RSDr values of the Medi·Ca SA method were generally the same level as those of the Baird-Parker method, and r2 ranged from 0.98 to 1.00. Product consistency and stability studies showed little variability between productions lots and a shelf-life of 16 months. Incubation time within the range of 22-26h and variations to the sample volume did not adversely affect the results. These results showed that the Medi·Ca SA method is a reasonable alternative to the reference method for selected food matrices and makes it possible to simultaneously detect and enumerate S. aureus in only 24h.

MC-Media Pad ACplus™ for Enumeration of Aerobic Counts in a Variety of Foods

The MC-Media Pad ACplus™ is a dry, rehydratable film medium for the enumeration of aerobic bacterial colonies. The performance of the method in a variety of foods was compared to that of U.S. reference methods: U.S. Department of Agriculture (USDA) Food Safety and Inspection Service (FSIS) Microbiology Laboratory Guidebook (MLG) Chapter 3.02 "Quantitative Analysis of Bacteria in Foods as Sanitary Indicators" (USDA/FSIS MLG 3.02); Standard Methods for the Examination of Dairy Products (SMEDP) Chapter 6 "Microbiological Count Methods, Standard Plate Count Method" (SMEDP 6); AOAC Official MethodSM 966.23 Microbiological Methods; and ISO 4833-1:2013 "Microbiology of the food chain-Horizontal method for the enumeration of microorganisms-Part 1: Colony count at 30 degrees C by the pour plate technique." The validated matrixes included raw chicken breast and raw ground pork for USDA/FSIS MLG 3.02; cream cheese and yogurt drink for SMEDP 6; parsley, vegetable juice, prawns, tuna pate, sandwiches, and pasta salad for AOAC Method 966.23, and raw chicken breast, raw ground pork, cream cheese, yogurt drink, parsley, vegetable juice, prawns, tuna pate, sandwiches, and pasta salad for ISO 4833-1:2013. In each matrix study, five replicates at each of three contamination levels were tested as paired test portions. All 10 matrixes were compared to the appropriate U.S. reference methods under MC-Media Pad ACplus standard-usage conditions (35 ± 1°C for 48 ± 2 h). Across all matrixes, the difference of mean log10 values ranged from -0.43 to 0.44, within the acceptable range of -0.50 to 0.50. The candidate method repeatability SD (sr) varied from 0.03 to 0.23 log10 CFU/g, comparing favorably to the reference method SD, which ranged from 0.06 to 0.30 log10 CFU/g. Seven matrixes were compared to the appropriate U.S. reference methods under MC-Media Pad ACplus rapid-usage conditions (35 ± 1°C for 24 ± 2 h). Of the 21 matrix/concentration combinations, only three instances of difference of mean >0.5 log were observed. The ranges of sr values of the rapid-usage candidate method (0.023-0.324) and the reference method (0.013-0.236) were similar for the seven matrixes tested. All 10 matrixes were compared to the International Organization for Standardization (ISO) reference method under MC-Media Pad ACplus alternate-method conditions (30 ± 1°C for 72 ± 3 h). All 10 matrixes yielded a mean difference between methods of <0.5 log, and the ranges of sr values were similar between the candidate alternate method (0.037-0.378) and the ISO reference method (0.037-0.437). The product consistency study demonstrated no significant difference between lots of product and supported the 2-year shelf life. Robustness testing yielded no significant differences when small variations were made in sample volume, incubation temperature, and incubation time. Thus, the data show equivalent or better performance of the MC-Media Pad ACplus method compared to the relevant reference methods in support of AOAC Performance Tested MethodSM certification.

Modelling the growth kinetics of Listeria monocytogenes in pasta salads at different storage temperatures and packaging conditions

The aim of this study was to model Listeria monocytogenes growth kinetics in ready to eat full meal pasta salads, containing fresh and cooked ingredients. With this aim, laboratory prepared salads, representing two formulations of commercial pasta salads, were spiked with L. monocytogenes and tested under categorised packaging and storage temperature conditions. L. monocytogenes enumeration results collected in 15 different laboratory prepared salad datasets were analysed with primary and secondary models. The models showing the best fit to describe L. monocytogenes growth kinetics in the laboratory prepared salads were then validated within commercial pasta salads. Baranyi no-lag was the best primary model fitting datasets collected at 12 °C, whereas the exponential model gave the best results for datasets collected at 4 °C. The maximum microbial specific growth rate (μmax) mean values obtained at 4 and 12 °C for salads packaged under air packaging conditions were 0.008 ± 0.003 and 0.036 ± 0.006 log10 (cfu/g) h−1, respectively. At the same temperatures, the μmax mean values obtained under modified atmosphere were 0.005 ± 0.005 and 0.026 ± 0.005 log10 (cfu/g) h−1, respectively. The Gamma secondary model predicted the growth kinetics of L. monocytogenes at both temperatures and packaging conditions and the μmax at the optimum temperature and the optimum pH for Listeria growth (μopt) estimated by the model corresponded to 0.247 ± 0.009 log10 (cfu/g) h−1. Baranyi model without lag phase was used to generate growth kinetics under different scenarios. In the comparison of the predicted log10 concentrations respect to the observed ones the residues rarely exceeded 1 Log10 cfu/g. The selected models can be applied to describe the growth kinetics of L. monocytogenes in similar types of pasta salads with comparable pH, shelf life and storage conditions.

MC-Media Pad SA (Sanita-kun SA) for the Enumeration of Staphylococcus aureus in a Variety of Foods.

MC-Media Pad SA (formerly known as Sanita-kun SA) is a dry rehydratable film medium for the enumeration of Staphylococcus aureus. The performance of the method in a variety of foods was compared with that of ISO 6888-1:1999, Microbiology of Food and Animal Feeding Stuffs - Horizontal Method for the Enumeration of Coagulase-Positive Staphylococci (Staphylococcus aureus and Other Species) - Part 1: Technique Using Baird-Parker Agar Medium. The validated matrixes included pastrami, a sliced cooked chicken roll, cooked prawns, cold-smoked salmon, pasta salad, sandwich spread, fresh uncooked pasta, infant cereal, custard, and raw-milk Brie cheese. In the matrix study, five replicates at each of three contamination levels were tested as paired test portions. Across all matrixes, the difference in mean log10 values ranged from -0.32 to 0.10, which was within the acceptable range of -0.50 to 0.50. Thus, all 10 matrixes met the acceptance criterion at all concentration levels. Further, only two matrixes, cooked prawns and raw-milk Brie cheese, had 95% confidence limits outside the -0.50 to 0.50 criterion, and these were at the lowest concentration level for each matrix. The candidate method sr varied from 0.03 to 0.22 log10 CFU/g. This compares favorably with the reference method SD, which ranged from 0.06 to 0.30 log10 CFU/g. The candidate and reference methods detected 51 of 53 inclusivity strains, with both methods not detecting the same two strains. The candidate method did not detect any of the 32 exclusivity strains, whereas the reference method did not detect 30 of the 32 exclusivity strains; the 2 strains detected by the reference method were S. delphini and S. hyicus, both developing atypical colonies on Baird-Parker plates. The product consistency study demonstrated no significant difference between lots of product and supported the 1 year shelf life. Robustness testing yielded no significant differences when small variations were made in sample volume, incubation temperature, and incubation time. Thus, the data show equivalent or better performance of the Sanita-kun SA/MC-Media Pad SA method compared with the International Organization for Standardization reference method, in support of AOAC Performance Tested MethodSM certification.

Microbial survey of ready-to-eat salad ingredients sold at retail reveals the occurrence and the persistence of Listeria monocytogenes Sequence Types 2 and 87 in pre-packed smoked salmon

BackgroundAs the preparation of salads involves extensive handling and the use of uncooked ingredients, they are particularly vulnerable to microbial contamination. This study aimed to determine the microbial safety and quality of pre-packed salads and salad bar ingredients sold in Singapore, so as to identify public health risks that could arise from consuming salads and to determine areas for improvement in the management of food safety.ResultsThe most frequently encountered organism in pre-packed salad samples was B. cereus, particularly in pasta salads (33.3%, 10/30). The most commonly detected organism in salad bar ingredients was L. monocytogenes, in particular seafood ingredients (44.1%, 15/34), largely due to contaminated smoked salmon. Further investigation showed that 21.6% (37/171) of the pre-packed smoked salmon sold in supermarkets contained L. monocytogenes. Significantly higher prevalence of L. monocytogenes and higher Standard Plate Count were detected in smoked salmon at salad bars compared to pre-packed smoked salmon in supermarkets, which suggested multiplication of the organism as the products move down the supply chain. Further molecular analysis revealed that L. monocytogenes Sequence Type (ST) 2 and ST87 were present in a particular brand of pre-packed salmon products over a 4-year period, implying a potential persistent contamination problem at the manufacturing level.ConclusionsOur findings highlighted a need to improve manufacturing and retail hygiene processes as well as to educate vulnerable populations to avoid consuming food prone to L. monocytogenes contamination.

The STARTEC Decision Support Tool for Better Tradeoffs between Food Safety, Quality, Nutrition, and Costs in Production of Advanced Ready-to-Eat Foods.

A prototype decision support IT-tool for the food industry was developed in the STARTEC project. Typical processes and decision steps were mapped using real life production scenarios of participating food companies manufacturing complex ready-to-eat foods. Companies looked for a more integrated approach when making food safety decisions that would align with existing HACCP systems. The tool was designed with shelf life assessments and data on safety, quality, and costs, using a pasta salad meal as a case product. The process flow chart was used as starting point, with simulation options at each process step. Key parameters like pH, water activity, costs of ingredients and salaries, and default models for calculations of Listeria monocytogenes, quality scores, and vitamin C, were placed in an interactive database. Customization of the models and settings was possible on the user-interface. The simulation module outputs were provided as detailed curves or categorized as “good”; “sufficient”; or “corrective action needed” based on threshold limit values set by the user. Possible corrective actions were suggested by the system. The tool was tested and approved by end-users based on selected ready-to-eat food products. Compared to other decision support tools, the STARTEC-tool is product-specific and multidisciplinary and includes interpretation and targeted recommendations for end-users.

Nutritional Properties of Ready-to-Eat Pasta Salads: Effect of Processing and Storage Conditions

Nutritional properties of ready-to-eat meals can vary greatly during storage due to the complexity of their food matrix. The nutritional properties of two types of ready-to-eat pasta salads differing in the processing of one of their ingredients (bell pepper) were evaluated during 12 days of storage at 4 and 12C. Salads with cooked (C) or uncooked (UC) red bell pepper were analyzed for proximate composition, dietary fiber content, lipid profile, ascorbic acid degradation kinetics and in vitro digestion of starch; rapid digestible starch and predicted glycemic index were also calculated. Results showed that vegetable processing significantly affected the ascorbic acid degradation, starch hydrolysis, as well as the fat and energy content of the salads. Nutritional properties of commercially available ready-to-eat pasta salads may significantly differ between manufacturers depending on the processing applied, storage temperature and time after production, and thus this should be seriously considered when evaluating their health implications. Practical Applications Despite the convenience and ease of preparation of ready-to-eat meals, consumers should be aware that health benefits claimed by some ingredients included in these products might be lessened by the storage conditions (time and temperature), type of processing and interaction with other constituents of the product. This work provides food manufacturers with an in depth insight on how these factors can affect the nutritional properties of their products and lead to foods that can retain the full potential of their nutritional qualities. More research regarding the health implications of the consumption of ready-to-eat foods is encouraged.

Appropriateness, acceptance and sensory preferences based on visual information: A web-based survey on meat substitutes in a meal context

The aim of this study was to investigate the appropriateness, attractiveness, use-intention and (un)desirable sensory properties of meat substitutes in different dishes based only on visual information. A web-based survey was developed to let consumers assess the use of meat substitutes in different dishes. The survey consisted of 38 key questions with subdivisions and was completed by 251 respondents. Six different dishes (spaghetti, rice, wrap, pizza, pasta salad, and soup) were rated for their appropriateness for the use of meat substitutes. Subsequently, appropriateness, attractiveness, and use-intention were rated based on photographs of the six dishes prepared with meat substitutes that differed in shape and appearance. Respondents also had to indicate (un)desirable sensory properties of meat substitutes for every dish. Spaghetti, rice and wrap were more appropriate for the use of meat substitutes than the other dishes. The most appropriate meat substitute–meal combinations were those that are similar to common Dutch meal combinations (e.g. spaghetti with mince and rice with pieces). Attractiveness and intention scores were in line with the appropriateness scores. Furthermore, we found that current users of meat substitutes and younger respondents gave higher appropriateness ratings. This study demonstrates that appropriateness of meat substitutes in a dish is related to attractiveness and use-intention and that meal context should be taken into account in the development of new meat substitutes.

Facts about Quinoa

The U.S. Department of Agriculture’s MyPlate nutrition guide recommends that Americans consume half of their grains from whole grain foods. Whole wheat bread and oatmeal are whole grain foods that are familiar to most Americans, but lots of other whole grain foods are also available. An example of an unfamiliar whole grain food is quinoa (pronounced keen-wa). Quinoa is a nutritious seed that is simple to prepare. It can be served as a hot cereal or side dish, as a cold salad similar to pasta salad, or it can be used in recipes in place of rice or other grains. It also has the advantage of being gluten free, which is a must for people diagnosed with celiac disease. Follow the link to learn more about quinoa and what it has to offer. This 3-page fact sheet was written by Alexandra Dati, Gail Kauwell, and Amy Simonne, and published by the UF Department of Family, Youth and Community Sciences, May 2014.&#x0D; FCS80035/FY1408: Facts about Quinoa (ufl.edu)

Flow cytometry immunodetection and membrane integrity assessment of Escherichia coli O157:H7 in ready-to-eat pasta salad during refrigerated storage

Over the past years, products of non-animal origin have been increasingly linked to foodborne diseases caused by the enterohemorrhagic pathogen Escherichia coli O157:H7. Contaminated fresh produce and derived ready-to-eat meals are of major concern, since no further or only minimal processing is applied. In this study, flow cytometry was evaluated as a rapid technique to detect E. coli O157:H7 by immunofluorescence, using polyclonal antibodies conjugated to R-phycoerythrin, in refrigerated ready-to-eat pasta salad containing acetic acid and benzoic acid. Signal filtering strategies were applied during sample analysis to reduce the limit of detection of the technique to 5 logCFU/g. Simultaneously with pathogen detection, physiological state was assessed by staining with the membrane integrity indicators propidium iodide and SYBR Green I. Fine tuning of dye concentrations and ratios allowed discrimination of not only cells with intact or damaged membranes, but also of cells with partially damaged membranes, which were considered injured cells. Then, changes in membrane integrity of inoculated E. coli O157:H7 cells were monitored throughout 14-day refrigerated storage. Most cells were injured at the beginning of refrigeration, but showed an intact membrane at the end. This suggests that injured E. coli O157:H7 cells underwent a membrane repair during exposure to refrigeration and acid stresses, and survived in ready-to-eat pasta salad. This highlights the importance of the implementation of control measures to limit the presence of this pathogen in non-animal origin food products. Additionally, the proposed immunodetection and membrane integrity three-color assay in food is a good tool to monitor the effect of a number of food-related treatments on E. coli O157:H7 cell membrane.

The interplay of health claims and taste importance on food consumption and self-reported satiety

Research has shown that subtle health claims used by food marketers influence pre-intake expectations, but no study has examined how they influence individuals’ post-consumption experience of satiety after a complete meal and how this varies according to the value placed on food taste. In two experiments, we assess how labeling a pasta salad as “healthy” or “hearty” influences self-reported satiety, consumption volume, and subsequent consumption of another food. Using MANOVA, Study 1 shows that individuals who report low taste importance consume less—yet feel just as satiated—when a salad is labeled “hearty” rather than “healthy.” In contrast, for individuals with higher taste importance, consumption and self-reported satiety are correlated and are both higher when a salad is labeled as “hearty” versus “healthy.” Study 2 primes taste importance, rather than measuring it, and replicates these findings for consumption, but not for self-reported satiety. There was no effect on the consumption of other foods in either study. Overall, our findings add to earlier work on the impact of health labels by showing that subtle food descriptions also influence post-intake experiences of satiety, but that the direction of the effects depends on taste importance and on the selection of direct or indirect measures of satiety.

Assessing the epidemiological data of Staphylococcus aureus food poisoning occurred in the State of Rio Grande do Sul, Southern Brazil.

Staphylococcal food poisoning is one of the most frequent foodborne illnesses worldwide and it is caused by the ingestion of food contaminated with enterotoxins produced by some strains of Staphylococcus (S.) aureus. In the State of Rio Grande do Sul (RS), Southern Brazil, S. aureus has been identified as the second most frequent agent of foodborne illnesses in the last two decades. The aim of the present study was to assess and analyse the epidemiological data of S. aureus food poisoning occurred in the State of RS during the years of 2000 to 2002. The official records of epidemiological investigations carried out by the Sanitary Surveillance Services of the State of RS were analysed. Among foodborne outbreaks for which aetiology was determined, S. aureus was identified as the responsible agent of 57 foodborne outbreaks, being 42 (74%) confirmed by microbiological analyses and 15 (26%) confirmed by clinical symptoms and/or epidemiological data. Staphylococcal outbreaks were responsible for the exposition of 5,991 persons, of which 1,940 (32%) were interviewed by the Sanitary Surveillance officers. The most affected age group corresponded to people with 20 to 49 years old (48%), where men (48%) and women (52%) were affected similarly. The main involved food vehicles were meats servings (35%), followed by pastries (25%), cheese (23%), pasta (11%) and potato salad with homemade mayonnaise (11%). The majority of the outbreaks occurred inside private homes (33%) followed by commercial food establishments (28%). Inadequate control of temperature and failures in general hygiene practices were identified as the main factors responsible for the outbreaks. In conclusion, S. aureus was an important food poisoning etiological agent in the State of RS during 2000 to 2002 and its prevention depends on control measures involving different parts of the food chain.