Fromagerie Beillevaire UK has recalled a batch of its ‘Brie de Meaux à la Truffe’ with a ‘use by’ date of 22 January 2016 because high levels of the bacterium Listeria monocytogenes have been found in the product.
KSWFoodWorld
Category Archives: Uncategorized
Research -Antimicrobial Efficacy of an Array of Essential Oils Against Lactic Acid Bacteria -Effect of Hops Beta Acids on the Survival of Unstressed- or Acid-Stress-Adapted-Listeria Monocytogenes and on the Quality and Sensory Attributes of Commercially Cured Ham Slices
Abstract
The essential oils of clove bud, cinnamon bark and thyme, and their individual compounds including allyl isothiocyanate (AIT), carvacrol, cinnamaldehyde, cinnamic acid, eugenol, and thymol were initially assessed for antimicrobial activity against 9 lactic acid bacteria (LAB) species. Carvacrol and thymol were the most inhibitory with MICs of 0.1% (v/v and w/v, respectively). Cinnamaldehyde, cinnamon bark oil, clove bud oil, eugenol, and thyme oil were moderately inhibitive (MICs = 0.2% v/v), while cinnamic acid required a concentration of 0.5% (w/v). AIT was not effective with MICs in excess of concentrations tested (0.75% v/v). The bactericidal capability of the oil components carvacrol, cinnamaldehyde, eugenol, and thymol were further examined against Pediococcus acidilactici, Lactobacillus buchneri, and Leuconostoc citrovorum. Thymol at 0.1% (w/v) was bactericidal against L. citrovorum (>4-log reduction), but resulted in a 2-log CFU/mL reduction against L. buchneri and P. acidilactici. Cinnamaldehyde at 0.2% to 0.25% (v/v) was effective against L. citrovorum, L. buchneri, and P. acidilactici, resulting in a >2-log reduction. All 3 organisms were susceptible to 0.2% carvacrol with >3-log reduction observed after exposure for 6 h. Eugenol was the least effective. Concentrations of 0.2% and 0.25% (v/v) were needed to achieve an initial reduction in population, >3-log CFU/mL after 6 h exposure. However, at 0.2%, P. acidilactici and L. buchneri recovered to initial populations in 48 to 72 h. Results indicate essential oils have the capacity to inactivate LAB that are commonly associated with spoilage of shelf stable low-acid foods.
Practical Application
Essential oils are plant derived compounds that consumers may view as more natural and preferred alternatives to synthetic preservatives. These oils have been demonstrated to have antibacterial and antifungal activity within food systems, and may be ideal additives to food formulations in order to meet the growing consumer demand for clean-label, organic or natural food products while preserving the quality and shelf-life of the product. These compounds have yet to be evaluated for their activity against common food spoilage organisms such as lactic acid bacteria, which is a first step in their adoption by the food industry.
Abstract
This study evaluated the antilisterial activity of hops beta acids (HBA) and their impact on the quality and sensory attributes of ham. Commercially cured ham slices were inoculated with unstressed- and acid-stress-adapted (ASA)-L. monocytogenes (2.2 to 2.5 log CFU/cm2), followed by no dipping (control), dipping in deionized (DI) water, or dipping in a 0.11% HBA solution. This was followed by vacuum or aerobic packaging and storage (7.2 °C, 35 or 20 d). Samples were taken periodically during storage to check for pH changes and analyze the microbial populations. Color measurements were obtained by dipping noninoculated ham slices in a 0.11% HBA solution, followed by vacuum packaging and storage (4.0 °C, 42 d). Sensory evaluations were performed on ham slices treated with 0.05% to 0.23% HBA solutions, followed by vacuum packaging and storage (4.0 °C, 30 d). HBA caused immediate reductions of 1.2 to 1.5 log CFU/cm2 (P < 0.05) in unstressed- and ASA-L. monocytogenes populations on ham slices. During storage, the unstressed-L. monocytogenes populations on HBA-treated samples were 0.5 to 2.0 log CFU/cm2 lower (P < 0.05) than control samples and those dipped in DI water. The lag-phase of the unstressed-L. monocytogenes population was extended from 3.396 to 7.125 d (control) to 7.194 to 10.920 d in the HBA-treated samples. However, the ASA-L. monocytogenes population showed resistance to HBA because they had a higher growth rate than control samples and had similar growth variables to DI water-treated samples during storage. Dipping in HBA solution did not adversely affect the color or sensory attributes of the ham slices stored in vacuum packages. These results are useful for helping ready-to-eat meat processors develop operational procedures for applying HBA on ham slices.
Practical Application
This study validated the antilisterial activities of HBA on commercially cured ham slices undergoing an HBA dipping treatment. Our results indicated that dipping the commercially cured ham slices into a 0.11% HBA solution (4.44 mg/kg of HBA on ham surfaces) inhibited unstressed-L. monocytogenes growth during storage, and the ASA-L. monocytogenes was cross-protected by HBA treatment. Moreover, application of 0.11% HBA to ham slices did not have negative effects on the color and sensory properties of the ham slices.
Posted in Uncategorized
Information -How To Avoid Restaurant Food Poisoning
Chipotle is learning the hard way rule number one of the restaurant business: Make sure people feel that your food is safe to eat. Whatever claims that you may make about your food being organic, locally sourced or from animals that were naturally raised, treated well, unstressed, did yoga, etc. will have little effect if people think your food results in food poisoning. (Disclaimer: Investigations into Chipotle’s food safety practices are ongoing and have not yielded definitive findings yet, and Chipotle never said that their cows do yoga.) Since July of 2015, Chipotle customers have suffered from two norovirus outbreaks in Simi Valley, Calif., and Boston, Mass., two E. coli outbreaks, and one Salmonella outbreak in Minnesota. Regardless of whether the outbreaks prove to be coincidences or the result of deficient food safety practices, they have left Chipotle squeezed into an increasingly tight burrito. Chipotle is now facing drops in sales, declining stock prices, a criminal investigation and most recently an investor lawsuit that claims that Chipotle failed to maintain food safety standards and disclose potential risks.
Posted in Uncategorized
Research -Recovering From Food Poisoning?
A bout with food poisoning usually resolves itself within a few days without any real treatment but there are ways to help your body as it recovers — paying particular attention to your food choices. You might not exactly feel like eating when you’re dealing with food poisoning but keeping some tips in mind might help ease your recovery. See full information at the link above.
Posted in Uncategorized
Information -Have You Washed Your Hands Lately?
The Holidays are now officially over and summer is still too far away to bear. This is the time of year when we are most likely to stay in and binge on some good old-fashioned TV. Sitting at home, all warm and cozy, surrounded by a plethora of snacks as far as the eye can see, is a perfectly satisfying way to watch the coldness of January pass by.
However, before you reach for that bowl of popcorn or grab a handful of chips from the tray, stop and ask yourself a very important question: Have my hands been properly washed recently? This is one of the simplest yet most effective ways to prevent the spread of many types of infection and illness, including foodborne illness. During these days of seemingly endless coughing and sniffling, we tend to touch our eyes, ears, and noses without even realizing it. In doing so, we can inadvertently be contaminating our food with a plethora of sickness-inducing germs.
Posted in Uncategorized
UK – IFST Courses London
IFST – Food Safety and the Production Environment – Selection, Use and Maintenance of Cleaning Equipment
Tuesday, January 26, 2016 – 09:30 to 11:15 SCI, 14-15 Belgrave Square, Londow, SW1X 8PS
IFST – Food Safety: Foodborne viruses – current work and challenges
Thursday, May 19, 2016 – 09:00 to Saturday, November 12, 2016 – 11:00
The Nutrition Society, 10 Cambridge Court, 210 Shepherds Bush Road, London, W6 7NJ
IFST -Food Safety in Retail
Wednesday, March 23, 2016 – 09:30 to 11:15
The Nutrition Society, 10 Cambridge Court, 210 Shepherds Bush Road, London, W6 7NJ
Posted in Uncategorized
Research -Cryptosporidium – Silver Particles – Cold Plasma – E.coli – Staphylococcus -Nisin
Applied and Environmental Microbiology
Silver Nanoparticles Decrease the Viability of Cryptosporidium parvum Oocysts
Oocysts of the waterborne protozoan parasite Cryptosporidium parvum are highly resistant to chlorine disinfection. We show here that both silver nanoparticles (AgNPs) and silver ions significantly decrease oocyst viability, in a dose-dependent manner, between concentrations of 0.005 and 500 μg/ml, as assessed by an excystation assay and the shell/sporozoite ratio. For percent excystation, the results are statistically significant for 500 μg/ml of AgNPs, with reductions from 83% for the control to 33% with AgNPs. For Ag ions, the results were statistically significant at 500 and 5,000 μg/ml, but the percent excystation values were reduced only to 66 and 62%, respectively, from 86% for the control. The sporozoite/shell ratio was affected to a greater extent following AgNP exposure, presumably because sporozoites are destroyed by interaction with NPs. We also demonstrated via hyperspectral imaging that there is a dual mode of interaction, with Ag ions entering the oocyst and destroying the sporozoites while AgNPs interact with the cell wall and, at high concentrations, are able to fully break the oocyst wall.
Applied and Environmental Microbiology
Mechanisms of Inactivation by High-Voltage Atmospheric Cold Plasma Differ for Escherichia coli and Staphylococcus aureus
Atmospheric cold plasma (ACP) is a promising nonthermal technology effective against a wide range of pathogenic microorganisms. Reactive oxygen species (ROS) play a crucial inactivation role when air or other oxygen-containing gases are used. With strong oxidative stress, cells can be damaged by lipid peroxidation, enzyme inactivation, and DNA cleavage. Identification of ROS and an understanding of their role are important for advancing ACP applications for a range of complex microbiological issues. In this study, the inactivation efficacy of in-package high-voltage (80 kV [root mean square]) ACP (HVACP) and the role of intracellular ROS were investigated. Two mechanisms of inactivation were observed in which reactive species were found to either react primarily with the cell envelope or damage intracellular components. Escherichia coli was inactivated mainly by cell leakage and low-level DNA damage. Conversely, Staphylococcus aureus was mainly inactivated by intracellular damage, with significantly higher levels of intracellular ROS observed and little envelope damage. However, for both bacteria studied, increasing treatment time had a positive effect on the intracellular ROS levels generated.
Applied and Environmental Microbiology
Impact of Nisin-Activated Packaging on Microbiota of Beef Burgers during Storage
Beef burgers were stored at 4°C in a vacuum in nisin-activated antimicrobial packaging. Microbial ecology analyses were performed on samples collected between days 0 and 21 of storage to discover the population diversity. Two batches were analyzed using RNA-based denaturing gradient gel electrophoresis (DGGE) and pyrosequencing. The active packaging retarded the growth of the total viable bacteria and lactic acid bacteria. Culture-independent analysis by pyrosequencing of RNA extracted directly from meat showed that Photobacterium phosphoreum, Lactococcus piscium, Lactobacillus sakei, and Leuconostoc carnosum were the major operational taxonomic units (OTUs) shared between control and treated samples. Beta diversity analysis of the 16S rRNA sequence data and RNA-DGGE showed a clear separation between two batches based on the microbiota. Control samples from batch B showed a significant high abundance of some taxa sensitive to nisin, such as Kocuria rhizophila, Staphylococcus xylosus, Leuconostoc carnosum, and Carnobacterium divergens, compared to control samples from batch A. However, only from batch B was it possible to find a significant difference between controls and treated samples during storage due to the active packaging. Predicted metagenomes confirmed differences between the two batches and indicated that the use of nisin-based antimicrobial packaging can determine a reduction in the abundance of specific metabolic pathways related to spoilage. The present study aimed to assess the viable bacterial communities in beef burgers stored in nisin-based antimicrobial packaging, and it highlights the efficacy of this strategy to prolong beef burger shelf life.
Posted in Uncategorized
Guyana – Gastroenteritis – One Dead
At least one person has died and a few scores are reportedly suffering from symptoms consistent with gastroenteritis. This is according to information filtered to the Ministry of Public Health to the Government Information Agency (GINA), which suggests that at least 60 individuals have sought care at the Baramita Health Centre manifesting symptoms of vomiting and diarrhoea.
It was in fact mounting cases of vomiting and diarrhoea that caused the Ministry to commence a close monitoring process of the indigenous locale.
The Region One area had an outbreak of gastro-enteritis infection in the past resulting in the deaths of a few children.
Posted in Uncategorized
Research -Whole-Genome Sequencing Analysis
Applied and Environmental Microbiology
Whole-Genome Sequencing Analysis Accurately Predicts Antimicrobial Resistance Phenotypes in Campylobacter spp.
The objectives of this study were to identify antimicrobial resistance genotypes for Campylobacter and to evaluate the correlation between resistance phenotypes and genotypes using in vitro antimicrobial susceptibility testing and whole-genome sequencing (WGS). A total of 114 Campylobacter species isolates (82 C. coli and 32 C. jejuni) obtained from 2000 to 2013 from humans, retail meats, and cecal samples from food production animals in the United States as part of the National Antimicrobial Resistance Monitoring System were selected for study. Resistance phenotypes were determined using broth microdilution of nine antimicrobials. Genomic DNA was sequenced using the Illumina MiSeq platform, and resistance genotypes were identified using assembled WGS sequences through blastx analysis. Eighteen resistance genes, including tet(O), blaOXA-61, catA, lnu(C), aph(2″)-Ib, aph(2″)-Ic, aph(2′)-If, aph(2″)-Ig, aph(2″)-Ih, aac(6′)-Ie-aph(2″)-Ia, aac(6′)-Ie-aph(2″)-If, aac(6′)-Im, aadE, sat4, ant(6′), aad9, aph(3′)-Ic, and aph(3′)-IIIa, and mutations in two housekeeping genes (gyrA and 23S rRNA) were identified. There was a high degree of correlation between phenotypic resistance to a given drug and the presence of one or more corresponding resistance genes. Phenotypic and genotypic correlation was 100% for tetracycline, ciprofloxacin/nalidixic acid, and erythromycin, and correlations ranged from 95.4% to 98.7% for gentamicin, azithromycin, clindamycin, and telithromycin. All isolates were susceptible to florfenicol, and no genes associated with florfenicol resistance were detected. There was a strong correlation (99.2%) between resistance genotypes and phenotypes, suggesting that WGS is a reliable indicator of resistance to the nine antimicrobial agents assayed in this study. WGS has the potential to be a powerful tool for antimicrobial resistance surveillance programs.
Applied and Environmental Microbiology
Whole-Genome Sequencing in Microbial Forensic Analysis of Gamma-Irradiated Microbial Materials
Effective microbial forensic analysis of materials used in a potential biological attack requires robust methods of morphological and genetic characterization of the attack materials in order to enable the attribution of the materials to potential sources and to exclude other potential sources. The genetic homogeneity and potential intersample variability of many of the category A to C bioterrorism agents offer a particular challenge to the generation of attributive signatures, potentially requiring whole-genome or proteomic approaches to be utilized. Currently, irradiation of mail is standard practice at several government facilities judged to be at particularly high risk. Thus, initial forensic signatures would need to be recovered from inactivated (nonviable) material. In the study described in this report, we determined the effects of high-dose gamma irradiation on forensic markers of bacterial biothreat agent surrogate organisms with a particular emphasis on the suitability of genomic DNA (gDNA) recovered from such sources as a template for whole-genome analysis. While irradiation of spores and vegetative cells affected the retention of Gram and spore stains and sheared gDNA into small fragments, we found that irradiated material could be utilized to generate accurate whole-genome sequence data on the Illumina and Roche 454 sequencing platforms.
Advanced Molecular Diagnostic Techniques for Detection of Food-borne Pathogens; Current Applications and Future Challenges.
The elimination of disease-causing microbes from the food supply is a primary goal and this review deals with the overall techniques availavle for detection of food-borne pathogens. Now-a-days conventional methods are replaced by advanced methods like Biosensors, Nucleic Acid-based Tests (NAT) and different PCR based techniques used in molecular biology to identify specific pathogens. Bacillus cereus, Staphylococcus aureus, Proteus vulgaris, Escherichia coli, Campylobacter, Listeria monocytogenes, Salmonella spp, Aspergillus spp. Fusarium spp. Penicillium spp., and pathogens are detected in contaminated food items which cause always diseases in human in any one or the other way. Identification of food-borne pathogens in a short period of time is still a challenge to the scientific field in general and food technology in particular. The low level of food contamination by major pathogens requires specific sensitive detection platforms and the present area of hot research looking forward to new nanomolecular techniques for nanomaterials, make them suitable for the development of assays with high sensitivity, response time and portability. With the sound of these we attemet to highlight a comprehensive overview about food-borne pathogen detection by rapid, sensitive, accurate and cost affordable in situ analytical methods from conventional methods to recent molecular approaches for advanced food and microbiology research
Posted in Uncategorized
USA -Salmonella Outbreak at Alabama Restaurant
A Salmonella outbreak at Johnny Ray’s in Pelham, Alabama is being investigated by the Alabama Department of Public Health. As of January 8, 2016, four people who ate at the restaurant at 309 Huntley Parkway have tested positive for Salmonella. Two of those sickened have matching patterns of a rare strain of Salmonella Enteritidis.
Posted in Uncategorized
