Publications by authors named "Declan J Bolton"

Cured meat products constitute one of the meat categories commonly consumed in Ireland and has been part of the Irish cuisine and diet for many years. Ham, gammon, and bacon are some of the products that involve curing as part of the traditional processing methods. Common among these products are high levels of salt and the addition of nitrites.

View Article and Find Full Text PDF

The present study compared the impact of two UV light devices: conventional UV lamp and UV-LED on the colour, pH, lipid and protein oxidation of fresh chicken breast meat aerobically stored at 4 °C for 10 days. Lipid oxidation was the most impacted quality attribute in UV lamp treated meat, unlike UV-LED that showed no effect compared to non-treated meat. Slight changes were observed in colour, pH and protein oxidation of chicken samples subjected to UV lamp and UV-LED.

View Article and Find Full Text PDF

This study investigated the combined effect of Ultraviolet (UV) light-emitting diode (LED) technology treatment with refrigerated storage of chicken breast meat over 7 days on Campylobacter jejuni, Salmonella enterica serovar Typhimurium, total viable counts (TVC) and total Enterobacteriaceae counts (TEC). An optimised UV-LED treatment at 280 nm for 6 min decreased inoculated S. Typhimurium and C.

View Article and Find Full Text PDF

Campylobacter jejuni remains a high priority in public health worldwide. Ultraviolet light emitting-diode technology (UV-LED) is currently being explored to reduce Campylobacter levels in foods. However, challenges such as differences in species and strain susceptibilities, effects of repeated UV-treatments on the bacterial genome and the potential to promote antimicrobial cross-protection or induce biofilm formation have arisen.

View Article and Find Full Text PDF

is commonly transmitted to humans from chickens. is the species most frequently associated with human illness, and the most prevalent species recovered from poultry. The objective of this study was to analyse a sub-population of from two broiler flocks on the farm and at slaughter using whole-genome sequencing to gain insights into the changes in the population during broiler production, including changes in virulence and antimicrobial resistance profiles.

View Article and Find Full Text PDF

Campylobacteriosis is one of the most common bacterial infections worldwide causing economic costs. The high prevalence of Campylobacter spp. in poultry meat is a result of several contamination and cross-contamination sources through the production chain.

View Article and Find Full Text PDF

EFSA was requested to estimate the cattle bovine spongiform encephalopathy (BSE) risk (C-, L- and H-BSE) posed by ruminant collagen and gelatine produced from raw material fit for human consumption, or from material classified as Category 3 animal by-products (ABP), to be used in feed intended for non-ruminant animals, including aquaculture animals. Three risk pathways (RP) were identified by which cattle could be exposed to ruminant feed cross-contaminated with ruminant collagen or gelatine: 1) recycled former foodstuffs produced in accordance with Regulation (EC) No 853/2004 (RP1), 2) technological or nutritional additives or 3) compound feed, produced either in accordance with Regulation (EC) No 853/2004 (RP2a) or Regulation (EU) No 142/2011 (RP2b). A probabilistic model was developed to estimate the BSE infectivity load measured in cattle oral ID (CoID )/kg, in the gelatine produced from the bones and hide of one infected animal older than 30 months with clinical BSE (worst-case scenario).

View Article and Find Full Text PDF

Two alternative methods for the production of compost from certain category 3 animal by-products (catering waste and processed foodstuffs of animal origin) were assessed. The first proposed a minimum temperature of 55°C for 72 h; the second 60°C for 48 h, each with a maximum particle size of 200 mm. The proposed composting processes were assessed by the BIOHAZ Panel for their efficacy to achieve a reduction of 5 log of or Senftenberg (775W, HS negative) and a 3 log reduction of the infectivity titre of thermoresistant viruses, such as parvovirus, in the composted material, as set out in Annex V, Chapter 3, Section 2 of Commission Regulation (EU) No 142/2011.

View Article and Find Full Text PDF

spp. are major causes of foodborne illness globally, and are mostly transmitted through the consumption and handling of poultry. infections have widely variable outcomes, ranging from mild enteritis to severe illness, which are attributed to host interactions and the virulence of the infecting strain.

View Article and Find Full Text PDF

Aims: Information on the gut microbiota of salmon is essential for optimizing nutrition while maintaining host health and welfare. This study's objectives were to characterize the microbiota in the GI tract of Atlantic salmon (Salmo salar) farmed in waters off the west coast of Ireland and to investigate whether there is a difference in microbiota diversity between the proximal and distal regions of the intestine.

Methods And Results: The microbiota from the proximal and distal intestine (PI and DI, respectively) of Atlantic salmon was examined using MiSeq Illumina high-throughput sequencing of the 16S ribosomal RNA gene.

View Article and Find Full Text PDF

Spoilage is a major issue for the seafood sector with the sale and exportation of fish limited by their short shelf-life. The immediate and storage effects of immersion (30 s at 20 °C) with 5% (/) citric acid (CA), 5% (/) lactic acid (LA), 5% (/) capric acid (CP) and 12% trisodium phosphate (TSP) (experiment 1) and essential oil components (EOC) (1% (/) citral (CIT), 1% (/) carvacrol (CAR), 1% (/) thymol (THY) and 1% (/) eugenol (EUG)) (experiment 2) on the concentrations of indicator (total viable counts (TVC) (mesophilic and psychrophilic) and total counts (TEC)), and spoilage organisms ( spp., lactic acid bacteria (LAB), , spp.

View Article and Find Full Text PDF

During the processing of Irish Brown Crab (), protein and moisture are released and losses up to 10% (by weight) are common. The objective of this study was to investigate the use of clean label ingredients to reduce this loss, without adversely affecting shelf-life or promoting the growth of spoilage bacteria. Following preliminary studies, 5% () sodium caseinate (SC) and (5%, ) potato starch (PS), with and without (0.

View Article and Find Full Text PDF

Human infections with foodborne pathogenic organisms are relatively well described in terms of their overt physical symptoms, such as diarrhea, abdominal cramps, vomiting, fever, and associated sequelae. Indeed, some of these are key for diagnosis and treatment, although it should be noted that, for some foodborne pathogens, the physical symptoms might be more diffuse, particularly those associated with some of the foodborne parasites. In contrast, the impact of these pathogens on mental health is less well described, and symptoms such as depression, anxiety, and general malaise are usually ignored when foodborne infections are recorded.

View Article and Find Full Text PDF

Background: The objective of this study was to characterise Campylobacter growth in enrichment broths (Bolton broth, brain heart infusion broth), caecal material (in vitro), and in the naturally infected live broilers (in vivo) in terms of mean lag periods and generation times as well as maximum growth rates and population (cell concentration) achieved.

Methods: Bolton and brain heart infusion broths and recovered caecal material were inoculated with 10 poultry strains of Campylobacter (eight Campylobacter jejuni and two Campylobacter coli), incubated under microaerobic conditions, and Campylobacter concentrations determined periodically using the ISO 10272:2006 method. Caeca from 10 flocks, infected at first thinning, were used to characterise Campylobacter growth in the live birds.

View Article and Find Full Text PDF

Despite over 30 years of research, campylobacteriosis is the most prevalent foodborne bacterial infection in many countries including in the European Union and the United States of America. However, relatively little is known about the virulence factors in Campylobacter or how an apparently fragile organism can survive in the food chain, often with enhanced pathogenicity. This review collates information on the virulence and survival determinants including motility, chemotaxis, adhesion, invasion, multidrug resistance, bile resistance and stress response factors.

View Article and Find Full Text PDF

Verocytotoxigenic Escherichia coli (VTEC) are a significant foodborne public health hazard in Europe, where most human infections are associated with six serogroups (O157, O26, O103, O145, O111 and O104). With the exception of O104, these serogroups are associated with bovine animals and beef products. This paper reviews our current knowledge of VTEC in the beef chain focusing on transmission and the factors which impact on survival from the farm through transport, lairage, slaughter, dressing, processing and distribution, in the context of the European beef industry.

View Article and Find Full Text PDF

A study was undertaken to investigate Salmonella in pigs at each step from birth to carcass. Environmental and/or pig samples were taken at birth, farrowing, 1st weaning, 2nd weaning, finishing, transport, lairage, bleeding and chilling of carcasses and tested for Salmonella. All isolates were characterised in terms of serotype, phage type (where relevant) and subtyping with pulsed field gel electrophosesis (PFGE).

View Article and Find Full Text PDF

The objective of this study was to establish the time-temperature combinations required to ensure the thermal inactivation of Yersinia enterocolitica during scalding of pork carcasses. A 2 strain cocktail of Y. enterocolitica (bioserotypes 2/O:5,27 and 1A/O:6,30) was heat treated at 50, 55 and 60°C in samples of scald tank water obtained from a commercial pork slaughter plant.

View Article and Find Full Text PDF

Thirty-nine Shiga toxin-producing Escherichia coli (STEC) O113 Irish farm, abattoir, and clinical isolates were analyzed in conjunction with eight Australian, New Zealand, and Norwegian strains for H (flagellar) antigens, virulence gene profile (eaeA, hlyA, tir, espA, espB katP, espP, etpD, saa, sab, toxB, iha, lpfA(O157/OI-141,) lpfA(O113,) and lpfA(O157/OI-154)), Shiga toxin gene variants (stx(1c), stx(1d), stx(2), stx(2c), stx(2dact), stx(2e), stx(2f,) and stx(2g)) and were genotyped using pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). All of the Irish strains were O113:H4, regardless of source, while all non-Irish isolates carried the H21 flagellar antigen. The stx(1) gene was present in 30 O113:H4 strains only, whereas the stx(2d) gene was common to all isolates regardless of source.

View Article and Find Full Text PDF

Four hundred and fifty beef animal hides and a similar number of carcasses were screened for STEC in 3 beef abattoirs over a 12 month period using PCR and culture based methods. 67% (301/450) of hides and 27% (122/450) of carcasses were STEC PCR positive. Forty isolates representing 12 STEC serotypes (O5:H-, O13:H2, O26:H11, O33:H11, O55:H11, O113:H4, O128:H8, O136:H12, O138:H48, O150:H2, O168:H8 and ONT:H11) and 15 serotype-virulotype combinations were identified.

View Article and Find Full Text PDF

Non-O157 Shiga toxin-producing Escherichia coli (STEC) strains are clinically significant food-borne pathogens. However, there is a dearth of information on serotype prevalence and virulence gene distribution, data essential for the development of public health protection monitoring and control activities for the meat and dairy industries. Thus, the objective of this study was to examine the prevalence of non-O157 STEC on beef and dairy farms and to characterize the isolates in terms of serotype and virulence markers.

View Article and Find Full Text PDF

The aim of this study was to examine the effect of pH and volatile fatty acids concentrations, as influenced by bovine diet, on the survival of Salmonella in inoculated rumen fluid and feces, thus providing preliminary data on the potential application of dietary manipulation as a preharvest control strategy to reduce Salmonella contamination at slaughter. The in vitro survival of nonacid- and acid-adapted (AA) Salmonella cocktails (Salmonella serovars: Dublin, Enteritidis, Newport, Typhimurium, and Typhimurium DT104) in rumen fluid and feces, collected from fistulated cattle fed five different diets ([1] grass, [2] grass + concentrate, [3] grass silage, [4] hay, and [5] a high grain diet), was examined at 6°C and 15°C (feces) and at 37°C (rumen fluid). The pH of the rumen fluid ranged from 5.

View Article and Find Full Text PDF

Verocytotoxigenic Escherichia coli (VTEC) are a good example of the evolution and emergence of pathogenic E. coli. Unknown before the late 1970s, these bacteria are a major cause of hemorrhagic colitis and hemolytic uremic syndrome worldwide.

View Article and Find Full Text PDF

This study determined the effects of (a) the short "heat shrink" treatment frequently applied to vacuum packed meats within normal commercial production, and (b) chill holding storage temperature, on the subsequent time to onset (TTO) of "blown pack" spoilage (BPS). Beef or lamb steaks were inoculated with 10³ CFU/cm² of spore suspensions of five gas producing clostridia, vacuum packed (VP) and treated as follows: no heat, 50°C/15 s, 70°C/10 s or 90°C/3 s. Samples were stored at -1.

View Article and Find Full Text PDF

The transferability of antimicrobial resistance from lactic acid bacteria (LAB) to potential pathogenic strains was studied using in vitro methods and mating in a food matrix. Five LAB donors containing either erythromycin or tetracycline resistance markers on transferable elements were conjugally mated with LAB (Enterococcus faecalis, Lactococcus lactis) and pathogenic strains (Listeria spp., Salmonella ssp.

View Article and Find Full Text PDF