Ready-to-eat Research Articles

Consumer attitudes and beliefs towards plant-based food in different degrees of processing – The case of Sweden

The aim of this study was to gain an understanding of consumer attitudes and beliefs on three different types of plant-based meat alternatives (covering two highly processed Plant Based Meat Alternatives (PBMA) products: a. vegetarian nuggets and b. soy mince, and pulses: c. pre-cooked beans). The analysis was based on data obtained from a questionnaire-based survey (N = 483) conducted in Sweden in November 2020. Consumers were separated into four food preference groups (all of whom consume meat): 1. flexitarians (meat reducers), 2. omnivores (mixed diet), 3. consumers who prefer meat and fish (avoid vegetarian food) and 4. consumers who explicitly prefer to only eat meat (avoid vegetarian food and fish). Products were chosen with the intention that they represent products from a scale ranging from a less processed product (pre-cooked beans), via soy mince (a processed PBMA product) to vegetarian nuggets (ready-to eat processed PBMA). The two PBMA products were also chosen to represent one convenience product (vegetarian nuggets) and one product mainly used as an ingredient (soy mince). Gender, age, education, consumption frequencies, food neophobia, health concern, ranking of qualities, awareness of climate change, and the link between food and climate were explored. The results illustrate differences and similarities between the four groups in attitudes and beliefs as well as the three products. Flexitarians represent the group that expresses the most positive and sustainably connected attitudes and beliefs. Results also show that for all groups, PBMA products are perceived as more modern, artificial and expensive compared to pulses, which, in turn, are perceived as healthier and a better climate choice compared to PBMA products. Meat and “meat and fish” eaters attach much importance to taste, perceived protein content, satiety and domestic origin (from Sweden), whereas omnivores are guided by taste, ease of cooking, health, climate change, and the link between food and climate. The outcome is expected to support policymakers and market actors in developing target group applied strategies addressing differences among the four food preference groups, thereby increasing consumers’ intake of sustainable plant-based protein-rich products.

Metagenetic characterization of bacterial communities associated with ready-to-eat leafy vegetables and study of temperature effect on their composition during storage

Ready-to-eat (RTE) and fresh-cut vegetables meet the current needs for healthy and easy-to-prepare food. However, raw vegetables are widely known to harbor large and diverse bacterial communities promoting spoilage and reducing their shelf-life. A better understanding of their bacterial community and the impact of various environmental factors on its composition is essential to ensure the production of high-quality fresh-cut produce. Therefore, a metagenetic amplicon approach, based on gyrB sequencing, was applied for deciphering the bacterial communities associated with the spoilage of RTE rocket and baby spinach and monitoring the changes occurring in their composition during storage at different temperatures. Our results indicated that Pseudomonas genus was the main spoilage group for both leafy vegetables. Specifically, Pseudomonas viridiflava was dominant in most samples of rocket, while a new Pseudomonas species as well as, Pseudomonas fluorescens and/or Pseudomonas fragi were highly abundant in baby spinach. A significant variability on bacterial species composition among different batches of each vegetable type was observed. In the case of baby spinach, the impact of temperature and/or storage time on bacterial microbiota was not explicitly revealed at batch-level. Concerning rocket, the storage time was the most influential factor resulting in the reduction of Pseudomonas species’ abundances and the parallel increase of lactic acid bacteria abundances. The results suggest that a large-scale sampling and further investigation of the various environmental factors shaping the microbiota are needed for gaining deeper knowledge of the diverse bacterial communities on RTE leafy vegetables and thus, enhance the quality of these products.

Effect of cold atmospheric plasma torch distance on the microbial inactivation and sensorial properties of ready-to-eat olivier salad.

This study aimed to investigate the effect of the cold atmospheric plasma torch (CAPT) nozzle distance from the surface of Olivier salad and the treatment time in the reduction of microbial load and sensory properties of the product simultaneously. In this study, the CAPT nozzle was placed at 3, 5, and 7 cm distances from the surface of the Olivier salad, and its efficiency in inactivating the microbial population, decimal reduction time (D-value), and sensory evaluation of the product were evaluated. The results showed that reducing the distance and increasing the plasma treatment time (30, 60, 90, and 120 s) both reduced the microbial load of the product. The maximum inactivation and the minimum D-value are related to the 3 cm distance for 120 s, which has been 3.77, 2.91, and 1.52 log CFU/g for Coliform, Total viable count (TVC), mold and yeast, respectively. The lowest D-value was related to Coliform (4.41 s). CAPT treatment had no significant sensible effect on the product's sensory characteristics compared to the control sample. The treated sample at a 3 cm distance for 90 s and the microbial reduction to an acceptable amount and high acceptancy from sensory evaluators were selected as the superior treatment in this study. Also, the results showed that CAPT could be used successfully in ready-to-eat (RTE) products.

Quality changes and experimental accelerated shelf‐life determination of ready‐to‐eat burgers made from striped catfish and salmon mince blend by thermal processing in retort pouches

Ready-to-eat (RTE) fish burgers were developed from the minced striped catfish (Pangasius hypophthalmus) and salmon (Salmo salar) mixed at the ratios of 100:0, 75:25, 50:50, 25:75 and 0:100 by thermal processing in flexible pouches using a water spray retort at a temperature of 121.1oC for 15 min. The RTE fish burgers were stored at the temperatures of 25, 35 and 45°C for 3 months. It was found that the diameter, weight, L* value and cohesiveness of the RTE fish burger decreased, while the a* ​​and b* values, hardness, chewiness and thiobarbituric acid (TBA) values of the RTE fish burger increased with longer storage time and higher storage temperatures. Total viable count, yeast and mold and Clostridium perfringens were below 10 CFU/g (detection limit) and coliform was below 3 MPN/g during 3 month-storage. The shelf-life prediction of the RTE fish burgers using Accelerated Shelf-life Test (ASLT) was conducted. The times of product decay were assessed at 3.92 and 1.40 months at the storage temperatures of 35 and 45°C, respectively. The TBA value was used as the shelf-life index of the RTE fish burgers. The calculated shelf-life of the RTE fish burgers stored at 20 and 25°C using Q10 technique were 13.1 and 7.8 months, respectively.

The live bacterial load and microbiota composition of prepacked “ready-to-eat” leafy greens during household conditions, with special reference to E. coli

Ready-to-eat (RTE) leafy greens are popular products that unfortunately have been associated with numerous foodborne illness outbreaks. Since the influence of consumer practices is essential for their quality and safety, the objective of this study was to analyze the microbiota of RTE products throughout shelf life during simulated household conditions. Products from different companies were analyzed in terms of plate counts, and resealed and unopened packages were compared. High bacterial loads were found, up to a total plate count of 9.6 log10 CFU/g, and Enterobacteriaceae plate counts up to 6.0 CFU/g on the expiration date. The effect of consumer practice varied, thus no conclusions regarding resealed or unopened bags could be drawn. The tested products contained opportunistic pathogens, such as Enterobacter homaechei, Hafnia paralvei and Pantoea agglomerans. Amplicon sequencing revealed that the relative abundance of major taxonomic groups changed during shelf life; Pseudomonadaceae and Xanthomonadaceae decreased, while Flavobacteriaceae and Marinomonadaceae inceased. Inoculation with E. coli CCUG 29300T showed that the relative abundance of Escherichia-Shigella was lower on rocket than on other tested leafy greens. Inoculation with E. coli strain 921 indicate growth at the beginning of shelf-life time, while E. coli 731 increases at the end, seemingly able to adapt to cold storage conditions. The high levels of live microorganisms, the detection of opportunistic pathogens, and the ability of E. coli strains to grow at refrigeration temperature raise concerns and indicate that the shelf life may be shortened to achieve a safer product. Due to variations between products, further studies are needed to define how long the shelf-life of these products should be, to ensure a safe product even at the end of the shelf-life period.

Enterotoxin- and Antibiotic-Resistance-Encoding Genes Are Present in Both Coagulase-Positive and Coagulase-Negative Foodborne Staphylococcus Strains

Food poisoning by staphylococcal enterotoxins (SE) is a major cause of foodborne illness, often associated with coagulase-positive staphylococci (CPS). The increase in the number of methicillin-resistant Staphylococcus aureus (MRSA) strains is another major problem associated with CPS. However, reports of the association of SE and methicillin-resistant Staphylococcus with coagulase-negative staphylococci (CNS) are beginning to re-emerge. In this context, the aim of this study is to investigate the presence of staphylococcal enterotoxin genes and to characterize the phenotypic and genotypic antimicrobial resistance in 66 isolates of Staphylococcus spp. (47 CNS and 19 CPS) recovered from ready-to-eat (RTE) street food sold in Maputo, Mozambique. Seven virulence genes encoding SE (sea, seb, sec, sed and see) and two toxins (hlb and sak) were screened by multiplex PCR (MPCR). Antimicrobial resistance against 12 antibiotics was evaluated by the disk diffusion method. The presence of genes encoding resistance to penicillin, methicillin, vancomycin and erythromycin (blaZ, mecA, vancA, vancB, ermA, ermB and ermC) were also screened by PCR. At least one of the seven virulence genes assessed in this study was detected in 57.9% and 51% of CPS and CNS isolates, respectively. In CPS isolates, the most frequent gene was hlb (47.4%), followed by sec (15.8%) and sea, seb and sed genes with 5.3% each. In CNS isolates, the most frequent gene was sec (36.2%) followed by sak (17%), hlb (14.9%), sed (12.8%) and seb (6.4%). Five of the twelve CPS in which virulence genes were detected were also antibiotic-resistant. All the CNS isolates harboring virulence genes (n = 27, 57.4%) were antimicrobial-resistant. The prevalence of multidrug resistance was higher (59.6%) in CNS than in CPS (26.3%) isolates. Regarding the presence of antibiotic-resistance genes, blaZ (penicillin-resistant) was the most frequent in both CPS (42.1%) and CNS (87.2%), followed by the mecA (encoding methicillin resistance) and vancA genes (vancomycin-resistant), which represented 36.8% and 31.6% in CPS isolates and 46.8% in CNS isolates, respectively. The prevalence of vancomycin-resistant staphylococci has been increasing worldwide and, to our knowledge, this is the first study to report the occurrence of vancomycin-resistant staphylococci in Mozambique. These results emphasize the need to investigate CNS isolates in parallel with CPS, as both constitute public health hazards, given their potential to produce SE and spread antimicrobial resistance genes.

Isolation, identification, and antibiogram studies of Escherichia coli from ready-to-eat foods in Mymensingh, Bangladesh.

Background and Aim:Ready-to-eat (RTE) foods are widely used at home, restaurants, and during festivals in Bangladesh. So it is very important to investigate possible microbial contamination in RTE foods. Therefore, this study aimed to determine the total coliform count (TCC), isolate, identify, and characterize the Escherichia coli in RTE foods. The antimicrobial sensitivity of E. coli obtained from RTE foods was also performed using 12 commonly used antibiotics.Materials and Methods:A total of 100 RTE food samples were collected aseptically and comprised of ten samples each: Burger, pizza, sandwich, chicken roll, chicken meat loaf, chicken fry, salad vegetable, ice-cream, yogurt, and milkshake sold in Mymensingh City. Samples were inoculated onto Eosin methylene blue agar and incubated at 37°C for 24 h. Isolation and identification of bacteria were performed based on cultural, staining, and biochemical properties, followed by a polymerase chain reaction.Results:The TCC in Chicken meat loaf, burger, pizza, sandwich, salad vegetable ice-cream, and yogurt samples were 3.57 ± 0.96, 3.69 ± 0.08, 3.50 ± 0.60, 2.60 ± 0.20, 4.09 ± 0.29, 4.44 ± 0.25, and 3.14 ± 0.30 mean log colony-forming units ± standard deviation/mL, respectively. The study found a higher prevalence of E. coli in RTE salad vegetable products than in RTE meat and milk products. Forty percent of the mixed vegetable salad samples showed positive results for E. coli. Whereas E. coli prevalence in RTE meat and milk products was 20% and 16.7%, respectively. All the 21 isolates were subjected to antibiotic susceptibility test against 12 different antibiotics. It was observed that 46.1% were susceptible, 16.6% were intermediate, 46.1% were resistant, and 47.6% were multidrug-resistant (MDR) among seven different antibiotic classes. E. coli isolates were resistant to cephalexin, ceftazidime, oxytetracycline, and ampicillin and sensitive to gentamycin, followed by kanamycin, ceftriaxone, colistin, and enrofloxacin.Conclusion:The study revealed that RTE foods are a serious issue from a public health point of view. To achieve a safer level of E. coli in RTE foods sold for human consumption, public food outlets must improve hygienic and good production procedures. Moreover, MDR E. coli in these foods pose serious public health threats.

Effect of Plasma Bubbling on Textural and Engineering Properties of Ready-to-Eat Pearl Millet Flakes and Puffs

Ready-to-eat (RTE) millet grain flakes and puffs are gaining importance in the modern era because of their nutritional and health benefits. In this work, air plasma has been generated and bubbled into pearl millet during soaking, followed by analyzing its flaking and puffing characteristics. The voltage 180, 200, and 220 V with airflow rates of 10 and 12 lph for 1 and 2 h was exposed to treat pearl millet samples. An increase in conductivity, total soluble solids (TSS), and drop in pH of the soaked medium was observed with the bubbling of plasma. The plasma bubbling exhibited an improvement in the pearl millet’s flaking and puffing properties. The noteworthy changes ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$P &lt; 0.05$ </tex-math></inline-formula> ) in expansion volume, bulk density, color, moisture content, crispiness, and hardness were observed in flaked and puffed samples. An increase in the expansion ratio (ER) of pearl millet flakes and puffs from 4.2 to 8.3 and 4.9 to 9.5 decreases in bulk density of flakes and puffs from 0.36 to 0.11 and 0.14 to 0.06 kg/m <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> , respectively, was noticed with the plasma bubbling. The textural properties like the crispiness of the flakes and puffs elevated, and hardness was reduced with the given treatments. The decrement in yellowness index (YI) and increase in whiteness index (WI) was observed in both flaked and puffed samples with the rise in exposure time. The synergistic effect of plasma reactive species in combination with hydration aids in improving grain properties and helps in diversifying the utilization of millet grains.

Food-to-Food Fortification of Ready-to-Eat Cereal-Based Porridges: A Potential Sustainable Food-Based Strategy to Improve Bioavailable Iron and Zinc in Plant-Based Diets

Abstract Objectives Iron and zinc deficiencies are prevalent in Africa, including urban populations, often due to monotonous plant-based diets low in bioavailable minerals. Food-to-food fortification (FtFF) is an emerging tool in the fight against mineral deficiencies. However, due to rapid urbanisation in Africa, demand for ready-to-eat (RTE) staple foods is increasing. This study investigated whether FtFF with plant foods rich in minerals (moringa leaves) and their bioavailability enhancers, organic acids (baobab fruit) and β-carotene (mango, papaya) at 2.5–14.9 g/100 g porridge with micronutrient premix (MP) can improve iron and zinc bioaccessibilities in extrusion-cooked wholegrain pearl millet-based porridges. Methods Three extrusion-cooked pearl millet-based porridges were formulated: 1) Pearl millet + carrot + mango + baobab + moringa; 2) Pearl millet + carrot + papaya + baobab; 3) Pearl millet + carrot + papaya + baobab + MP (iron (2.1 mg) zinc (1.65 mg), vitamin A (840 IU)). Raw pearl millet served as the control. Porridge mineral, phytate and total phenolics contents were determined. In vitro equilibrium dialysability assay was performed to predict mineral bioavailability. Results The RTE FtFF-porridges had higher bioaccessible iron than pearl millet (p &amp;lt; 0.05), in terms of percentage and amount, by up to 23-fold. However, the porridges were unnaturally high in iron due to contamination from the extruder cooker parts. FtFF with combinations of carrot, papaya, baobab plus MP or with carrot, mango, baobab plus moringa leaves increased bioaccessible zinc (p &amp;lt; 0.05), in terms of percentage and amount, by up to 4-fold, with the porridge containing MP enhancing iron and zinc bioaccessibility the most. The organic acids and β-carotene contents plus the low pH (3.0–5.2) of the food fortificants likely enhanced the solubility of the contaminating iron and the intrinsic iron and zinc in the porridges. Extrusion cooking reduced the porridges’ phytate contents, by 35–50%, hence, likely contributed to the increased mineral bioaccessibilities. Conclusions Thus, such ready-to-eat food-to-food fortified wholegrain cereal-based porridges may be a sustainable food-based strategy to improve bioavailable iron and zinc in the diet of at-risk urban populations in Africa. Funding Sources USAID, South Africa National Research Foundation/TWAS.

A study on breakfast consumption and skipping pattern among college students in Coimbatore

Background: Breakfast, an important meal in a day provides 1/3rd of the days’ requirement. Beyond satisfying hunger, breakfast improves both the health and cognitive ability of individual. This study aimed at exploring the breakfast consumption pattern, prevalence of skipping breakfast, reasons for skipping and perceptions toward this meal. The study also aimed to find a solution to reduce the prevalence of breakfast skipping. Methodology: A cross-sectional survey was conducted among 612 undergraduate students from four colleges comprising of 2 Engineering and 2 Arts and Science colleges in Coimbatore district, Tamil Nadu. The questionnaire included socio-demographic, perception about each meal, reasons for skipping breakfast and their preference towards breakfast choices. Results: In a sample of 612 undergraduate students, 73 percent reported skipped any one of the meals, of which breakfast accounts to 66 percent. Though 59 per cent participants believed that breakfast is an essential meal contradictorily, they skip breakfast. Reasons for breakfast skipping were enlisted to be lack of time (37 per cent) followed by not feeling hungry, waking up late. About 86 per cent of the students showed a positive response towards the acceptance of Ready-To-Eat (RTE) breakfast due to lack of time in the morning. They expressed this kind of RTE will help them to consume breakfast regularly. Conclusion: Creating awareness on importance of breakfast alone would not contribute to reduce breakfast skipping. As preferred by the participants, development of affordable and available RTE (on-the-go meals) convenient foods would help them to consume it regularly thereby enhancing the nutritional and health status of the college students.

Growth potential of Salmonella enterica in thirty‐four different RTE vegetable salads during shelf‐life

SummaryThirty‐four different ready‐to eat (RTE) vegetable salads were inoculated with a cocktail of three Salmonella enterica strains, and stored under a modified atmosphere for up to 168 h at 4, 7, 12 and 16°C. Eighteen (18) of the salad samples comprised of two or more vegetable ingredients (also referred to as MV RTE salads), and 16 were made up of single vegetable ingredients (SV RTE salads). Generally, the growth potential of inoculated S. enterica varied depending on temperature and type of RTE vegetable salad. The higher temperature was generally more favourable for the growth of S. enterica. Among all 34 salad samples, 5, 11, 18 and 24 salad samples supported the growth of Salmonella at 4, 7, 12 and 16°C, respectively. All salads consisting of multiple vegetable ingredients except two: one comprised of carrots, lettuce and beetroot and another comprised of white cabbage and purple cabbage, supported the growth of Salmonella at high temperatures (either 12 or 16 or both 12 and 16°C). Although the growth of Salmonella was variable in the different types of RTE salads, and growth was generally low at 4°C, Salmonella exhibited consistently minimal growth in some vegetable salads such as those comprised of carrots, lettuce and beetroot, carrots, beetroots, cabbage and cucumber, as well as one comprised of beetroot and corn at all temperature conditions tested.

Behaviour and adhesion capacity of Listeria monocytogenes on Mozzarella di Bufala Campana PDO cheese and in fluids involved in the production process

Listeria monocytogenes is a foodborne pathogen for humans. It can be found in ready-to-eat (RTE) products and its presence represents one of the biggest food safety concerns. Most of the cases of cheese contamination reported by the Rapid Alert System for Food and Feed (RASFF) in the last 10 years did not involve Mozzarella di Bufala Campana (MBC) Protected Designation of Origin (PDO) cheese. Suddenly, in the last years, RASFF has disposed of the withdrawn from the market of this product contaminated with L. monocytogenes on two different occasions (RASFF 2018/1198 and 2018/2459), and the Canadian Food Inspection Agency disposed one withdrawn in 2019. Following these events, this study aimed to evaluate the behaviour of L. monocytogenes in Mozzarella di Bufala Campana PDO cheese. First of all, the adhesion capacity of the pathogen to MBC cheese was studied through microbial challenge tests simulating the passage of MBC in hardening water and in covering liquid used for cheese storage during the production process. In addition, the ability of L. monocytogenes to grow in MBC cheese and covering liquid during shelf life, at refrigerated condition, was evaluated also this time employing microbial challenge tests. Results demonstrated that L. monocytogenes can adhere to the surface of the cheese and be released during the contact of contaminated cheese with other fluids. However, the presence of an abundant microbiota on the cheese exerted a protective role against this pathogen preventing the growth of L. monocytogenes. Indeed, the pathogens artificially contaminating the covering liquid at 2 log CFU/mL and 4 log CFU/mL remained at the inoculum level during 32 days of storage at 4 °C.

Multijurisdictional Outbreak of Enterohemorrhagic Escherichia coli O157 Caused by Consumption of Ready-to-Eat Grilled Skewered Meat in Niigata, Japan.

Enterohemorrhagic Escherichia coli O157 (EHEC) causes severe complications such as hemolytic uremic syndrome. Contaminated ready-to-eat (RTE) food is one of the vehicles of multijurisdictional outbreaks of foodborne disease worldwide. Multijurisdictional (covering cities, towns, and villages) outbreaks of EHEC are usually linked to an increase in cases, and here we describe such an outbreak involving 29 cases in October 2017 in the Niigata Prefecture. After prefecture-wide active case finding, we conducted a case-control study of 29 cases with eligible data who tested positive for EHEC. To determine the association of the outbreak with risk factors, we compared these cases with 38 controls selected from family and acquaintances who were both symptom free and tested negative for EHEC. The largest number of cases was in the 20-29-year age group (7/29; 24%) and most were women (20/29; 69%). All 29 cases had an identical or similar multilocus variable number tandem-repeat analysis (MLVA) profile. Of these, 76% (22/29) had consumed some type of grilled skewered meat. Also, 69% (20/29) had consumed grilled skewered meat produced by company X. EHEC infection was strongly associated with the consumption of grilled skewered meat produced by any food processing company (odds ratio [OR] = 11.8, confidence interval [95% CI]: 3.7-37.4) and by company X (OR = 9.8, 95% CI: 3.2-30.7). At company X, the skewered meat was grilled to 95°C and then removed from the grilling area to meat trays. The meat trays were not sufficiently washed and disinfected. Testing indicated that the facility was negative for EHEC but four asymptomatic employees tested positive for EHEC. Company X was temporarily closed and voluntarily recalled the foods. We recommend that all employees sufficiently wash and disinfect meat trays to prevent contamination of RTE food, avoid cross-contamination of grilled skewered meat through the environment by regularly cleaning the facility, and appropriately practice self-health care.

Identifying elements of a ready-to-eat meal desired by older adults

The population of older adults is rapidly growing, and undernutrition remains a concern. Properly formulated ready to eat (RTE) meals can provide older adults with convenient, nutritious meals that require minimal preparation. The study objective of this work was to uncover which properties and components of RTE meals were most important to older adults. 285 participants (mean age = 68.3 years) from Canada (n = 167) and the United States (n = 118) completed a two-part online survey. First, demographic information, including oral health survey and medication history was gathered. Rating-based conjoint analysis was then employed to identify RTE meal preferences. Meal ideas (n = 24) were created via a half-factorial design comprised of four concepts: taste theme (Asian, Latin, Mediterranean), protein source (chicken, fish, alternative protein, egg), spice (presence/absence), and fiber source (grains/vegetables). Participants indicated their expected liking and purchase intent of each meal idea. Results from the oral health survey found significant correlations between age and medication intake (R = 0.219, p = 0.0002), and frequencies of loss of taste and loss of smell (R = 0.800, p < 0.0001). Regarding meal components, protein source had the greatest importance to the total population (relative importance = 51.5%) with chicken having the greatest positive influence on liking (utility value = 0.31). A greater preference for the Mediterranean taste theme was observed in the Canadian respondents (p = 0.0002). Segmentation of the full dataset revealed four clusters based on relative importance of meal components. Cluster 1 (n = 25) contained participants preferring the presence of chicken and not fish, Cluster 2 (n = 190) was positively affected by the inclusion of chicken and fish, Cluster 3 (n = 42) contained individuals negatively affected by the presence of spice, and Cluster 4 (n = 23) contained individuals who preferred vegetarian options. In future research, meals that contain chicken or are vegetarian-friendly will be pursued.

Comparative immunomodulatory effects in mice and in human dendritic cells of five bacterial strains selected for biocontrol of leafy green vegetables

The market for ready-to eat vegetables is increasing, but unfortunately so do the numbers of food-borne illness outbreaks related to these products. A previous study has identified bacterial strains suitable for biocontrol of leafy green vegetables to reduce the exposure to pathogens in these products. As a tentative safety evaluation, five selected strains (Rhodococcus cerastii MR5x, Bacillus coagulans LMG P-32205, Bacillus coagulans LMG P-32206, Pseudomonas cedrina LMG P-32207 and Pseudomonas punonensis LMG P-32204) were individually compared for immunomodulating effects in mice and in human monocyte-derived dendritic cells (MoDCs). Mice receiving the two B. coagulans strains consistently resemble the immunological response of the normal control, and no, or low, cell activation and pro-inflammatory cytokine expression was observed in MoDCs exposed to B. coagulans strains. However, different responses were seen in the two models for the Gram-negative P. cedrina and the Gram-positive R. cerastii. Moreover, P. punonensis and B. coagulans increased the microbiota diversity in mice as seen by the Shannon-Wiener index. In conclusion, the two strains of B. coagulans showed an immunological response that indicate that they lack pathogenic abilities, thus encouraging further safety evaluation and showing great potential to be used as biocontrol agents on leafy green vegetables.

Presence and Virulence Characteristics of Shiga Toxin Escherichia coli and Non-Shiga Toxin-Producing Escherichia coli O157 in Products from Animal Protein Supply Chain Enterprises in South Africa.

Consumption of food that is contaminated with Shiga toxin–producing Escherichia coli (STEC) has been linked to serious foodborne disease outbreaks. Our aim was to provide a descriptive study on the presence and virulence factors of STEC and non-STEC O157 isolates recovered from 2017 diverse meat and meat product samples from all provinces of South Africa (n = 1758) and imported meat from South Africa's major ports of entry (n = 259). A cross-sectional study was undertaken to analyze raw intact meat, raw processed (nonintact) meat, and ready-to-eat (RTE) meat from cattle, game, sheep, pork, and poultry. Isolation was performed using International Organization for Standardization-based microbiological techniques, while detection and characterization were performed using real-time PCR (RT-PCR) and conventional PCR targeting the stx1, stx2, eae, and ehxA genes. A total of 28 of 1758 (1.59%; confidence interval [CI] 1.1–2) samples from the domestic market tested positive (n = 10 Escherichia coli O157:H7; n = 14 Escherichia coli O157: non-H7; and n = 4 non-O157 STEC), while 4/259 (1.54%; CI 0.4–4) samples from ports of entry tested positive for Escherichia coli O157:H7 based on RT-PCR. On average, diverse samples from domestic meat and meat products from cattle showed the highest number of positive samples (22/1758; 1.3%; CI 0.8–2). RT-PCR detected more positive samples (n = 32) compared with culture (n = 17). Sixteen different virulence factor combinations were observed. Our findings demonstrate a relatively low presence of diverse STEC strains along the meat value chain. To our knowledge, this is the first extensive report in South Africa to analyze STEC and non-STEC O157 from local and imported samples from many animal species. This is important as it reveals virulence factors in STEC strains circulating in meat and meat products in South Africa, which contribute to the risk of infection.

Risk and socio-economic impact for Staphylococcus aureus foodborne illness by ready-to-eat salad consumption

Microbial risk assessment is a valuable tool to provide scientific evidence to control food safety. Therefore, this study evaluated the risk of foodborne illness caused by Staphylococcus aureus in ready-to-eat (RTE) salad products and economic impact. The prevalence of S. aureus in salads, the RTE salad consumption, and distribution conditions (time and temperature) in market parameters were determined, and the data were analysed using the @RISK program to determine the appropriate probabilistic distribution. Predictive models were developed to describe the fate of S. aureus under distribution conditions. A simulation model was prepared with the collected data to calculate the risk of illness per person per day, and this risk was used to calculate the economic impact. S. aureus was detected in 2% of RTE salads, and the initial contamination level was calculated using the Beta distribution. Baranyi model was used to calculate the maximum specific growth rate (μmax), lag phase duration (LPD), and the secondary models well described the temperature effect on LPD and μmax with R2 values of 0.973–0.979. Also, the root mean square error values of 0.362 suggested that the model performance was appropriate. Lognormal distribution estimated that the average daily consumption amount and ratio was 137.7 g and 9.8%, respectively. The simulation model showed that the average probability of S. aureus foodborne illness following RTE salad consumption was 2.1 × 10−9 per person per day. The probability was used to estimate the socio-economic burden, and the annual socio-economic cost was calculated as $48,343.

Use of DNA Barcoding to Identify Species of Raw Ready‐To‐Eat Seafood Products Sold in Orange County, CA

DNA barcoding is widely used to identify commercial fish species sold in the U.S and internationally. This method is based on DNA sequencing of a standardized region of DNA from a sample. Sequences can then be analyzed against the Barcode of Life Data system (BOLD) for species identification. Additional analysis of samples by a method called DNA mini‐barcoding can be used for samples that cannot be correctly identified to the species level by the traditional DNA barcoding method. While relatively high levels of seafood mislabeling have been reported for sushi dishes, few studies have investigated mislabeling of other raw, ready‐to‐eat (RTE) seafood such as poke and ceviche. The objective of this study was to evaluate the presence of species mislabeling in raw, RTE seafood products in Orange County, CA. DNA barcoding and mini‐barcoding were used to investigate 70 samples of sushi, ceviche, and poke collected from various locations in Orange County. All samples underwent DNA barcoding, followed by species identification using the BOLD database. Six samples underwent further analysis with mini‐barcoding. The FDA seafood list was used to identify common and acceptable market names. The results showed that 13 samples were substituted on the basis of species, and 20 samples did not have an acceptable market name. The overall mislabeling rate for all samples combined was 52.3% (33/63). These results indicate a need for greater scrutiny of labeling practices for raw, RTE seafood sold in Orange County, California.

Microbial Qualities of Parasites and Foodborne Pathogens in Ready to Eat (RTE) Fresh-cut Produces at the On/Offline Markets

Microbial Qualities of Parasites and Foodborne Pathogens in Ready to Eat (RTE) Fresh-cut Produces at the On/Offline Markets

Food safety inspection of tas kebab and salad processing line in a catering company

This study was conducted to evaluate the sufficiency of food safety practices in a catering company. The presence of some pathogenic and indicator bacteria was monitored in the samples collected from raw materials, food, food contact surfaces and workers' hands and various steps of the tas kebab (a Turkish meat stew) and salad processing lines. Bacillus cereus was found in ready-to-eat (RTE) tas kebab and RTE salad, while Listeria monocytogenes was isolated from RTE salad. Furthermore, it was observed that RTE salad contained coagulase-positive Staphylococcus aureus without staphylococcal enterotoxin production. The swab samples obtained from cutting board surfaces, knives and workers' hands contained high counts of total aerobic bacteria and some samples were contaminated with coliforms and coagulase-positive/negative staphylococci. The presence of B. cereus and L. monocytogenes in RTE foods is a serious threat to public health, especially in the catering business. Preventing the presence of toxin-producing bacteria in RTE food is a fundamental action. Also, the occurrence of L. monocytogenes in RTE salad and B. cereus in RTE tas kebab/salad samples showed insufficient cleaning/disinfection practices. As a result, hygiene practices and regular monitoring in the catering business are necessary for food safety.