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Introduction. Hyposmia is a frequent symptom of Parkinson's disease (PD), which greatly impacts patients' flavor perception and their quality of life. However, PD patients recognize some odors better than others. Identifying which food odors are still recognized by PD patients may be useful for flavor enhancement. Our aim was to evaluate the olfactory identification of Sniffin' Sticks and spice odorants in PD patients and healthy controls (HC), to identify the impact of synthetic odorants compared with real-life food and the impact of odor familiarity and pleasantness on odorant identification in PD patients. Methods. Sniffin' Sticks odorant identification was evaluated in 80 PD patients and 105 age-matched HC. In a subset, the spice odorant identification was evaluated. Results. The mean total score was higher for the Sniffin' Sticks than for the spice odor identification test in all participants (55.4% versus 22.5%). Sniffin' Sticks orange, peppermint, rose, and fish odorants were best correctly identified by PD patients, by 62.5, 53.8, 52.9, and 57.5%, respectively. Of the spice odor identification test, garlic and "no stimulus" were best correctly identified by PD patients, by, respectively, 38.2 and 67.6%. HC identified most Sniffin' Sticks odorants and spices better than PD patients. Odorant familiarity determined real-life food odorant identification. Conclusion. This study demonstrates that some food odorants, both the commercial Sniffin' Sticks as natural odorants, are still recognized by PD patients. Sniffin' Sticks were better recognized compared with real-life odorants, by both HC and PD patients. Odorant familiarity determined PD patients' odorant identification; therefore, familiar food odorants may have potential for a future flavor enhancement. Implications. This is the first study, to our knowledge, to evaluate real-life food odor identification in PD patients. Our results provide a first step towards patient-appropriate flavor enhancement strategies in PD. [ABSTRACT FROM AUTHOR]

People in need of care, chronic or acute, often present problematic food intake and special nutritional needs. Integrated, person-centred and pro-active food and nutritional care delivery has been proven effective for people in health care. However, skills mismatches have been reported in different professions involved, which also applies to the role of chefs in healthcare. The EU funded project NECTAR aims at closing this gap by creating a new job profile, called Chef Gastro-Engineering (CGE). The current publication summarizes the status quo in hospitals and gives a perspective on the future role of chefs in integrated healthcare delivery. [ABSTRACT FROM AUTHOR]

To meet their growing interest and to counteract the increase of diet-related diseases worldwide, the field-to-fork concept comprises opportunities for providing consumers with nutritious and health-beneficial food. Although health-beneficial effects have been ascribed to specific food compounds, most often in vivo human evidence and/or accepted health/nutrient claims are lacking. Part I of this review gives an overview of possible sources of macronutrients, micronutrients and other compounds (e.g. secondary metabolites) with proven in vivo human health-beneficial effects and/or health/nutrition EFSA claims. More importantly, it focuses on opportunities within the primary production to obtain/increase/maintain sufficient amounts of such compounds: (i) crop choice, breeding, crop husbandry and environment, harvesting/storage for plant-derived products, (ii) breeding stock selection, feeding strategies and animal husbandry for animal-derived products. However, providing food commodities/products with sufficient amounts of such nutrients is one thing, but aspects like, for example, bioavailability and interindividual variability play a role as well. As such, a balanced diet should be aimed at by means of differentiation within the dietary pattern while considering foods as a whole rather than a sum of compounds. Within this concept, all factors/actors of the agriculture-food-health trichotomy should be integrated as much as possible to provide consumers with health-beneficial food commodities/products. [ABSTRACT FROM AUTHOR]

Dysphagia is a frequent symptom in Parkinson's disease (PD). Thickening liquids facilitates safe swallowing, however, low treatment compliance is a major issue, due to patients' dislike of thickened liquids. Some studies suggest a negative impact of gum‐based thickeners, currently most used in clinical practice, on sensory properties compared to starch‐based thickeners. This has not yet been investigated in PD. This study's aim was to compare taste, texture, and aroma of gum‐based and starch‐based thickened soups in participants with PD. Gum‐based resource thicken up clear (RTUC) and starch‐based kitchen products potato starch (PS) and quinoa flour (QF) were evaluated in broccoli soup. Texture, aroma, and taste were characterized by rheology, volatile, and sensory profiling. Thickened soups were evaluated in participants with PD and controls through a paired comparison test. Reduced release of 61.4%, 46.2%, and 38.5% of volatiles was observed after thickening with RTUC, PS, and QF, respectively. Overall taste intensity was reduced in RTUC‐ and PS‐thickened soup, respectively. Taste and aroma of PS‐thickened soup were considered more intense by 70.3% and 63.8% of all participants, respectively (n = 36 PD, n = 41 controls), 56.3% preferred the PS‐thickened soup's texture. Taste and aroma of QF‐thickened soup were considered more intense by 68.1% and 65.6% of all participants, respectively (n = 47 PD, n = 31 controls), 58.0% preferred the QF‐thickened soup's texture. Starch‐based thickeners demonstrated higher taste and aroma intensity. However, volatile and sensory profiling demonstrated reduced taste and aroma in all thickeners. Combining kitchen products with flavor enhancers may increase palatability of thickened beverages. [ABSTRACT FROM AUTHOR]

European brown shrimp (Crangon crangon) have great commercial value. Recently, an increasing demand for fresh shrimp has led fishermen to land part of their catch alive. In the present study, the effects of various parameters on the post-catch survival of brown shrimp were investigated by housing them in natural seawater and monitoring survival for two weeks. In a first experiment shrimp survival was tested under high population densities at different temperature settings ranging between 8°C and 21°C. A second experiment investigated the effect of a sand layer in the holding tanks when shrimp were housed at low population densities. Finally, the impact of onboard sorting with a rotary sorting riddle on subsequent survival was assessed. A higher survival rate was found at lower water temperatures. The use of a sand substrate did not significantly improve survival but did result in a more even distribution of shrimp across the bottom of the holding tanks. Onboard sorting with a mechanical rotary sorting riddle did not significantly affect the survival of brown shrimp during the first four days of holding although injuries sustained during onboard handling resulted in high mortality at the time of landing. [ABSTRACT FROM AUTHOR]

To optimize product quality of the cooked brown shrimp ( Crangon crangon ), quantitative data on the influence of all relevant process parameters (treatment time and temperature) on several quality attributes is required. Surprisingly, kinetic data and models on heat induced inactivation of important endogenous spoilage enzymes of the brown shrimp are not available today. In this study the thermal inactivation kinetics of the most important spoilage enzymes, proteases and polyphenoloxidase (PPO), were determined from isothermal heat treatments of enzyme extracts of the cephalothorax. For both enzymes, inactivation kinetics showed first order decay(s). Proteases showed two distinct stability fractions. A labile fraction, representing 42 ± 2% of the total activity with k l ,60 °C = 0.94 ± 0.14 min −1 and E a , l = 178 ± 8.5 kJ/mol, and a stable fraction, representing 58 ± 2%, with k s ,60 °C = 0.020 ± 0.002 min −1 and E a , s = 155 ± 7.0 kJ/mol. PPO showed a single fraction with k 60 °C = 1.58 ± 0.02 min −1 and E a = 161 ± 2.2 kJ/mol. Based on these results, the proteolytic activity, in particular the thermostable fraction, should be considered as a target in thermal processing of brown shrimp in relation to enzyme induced product quality changes during storage. [ABSTRACT FROM AUTHOR]

Attachment of enteric pathogens such as Escherichia coli O157:H7 to fresh produce is a crucial first step for contamination to occur, and irrigation water (IW) is considered a potentially important preharvest introduction route. In a natural situation, E. coli O157:H7 may be present in the irrigation water for some time and may, therefore, be starved. Most research, however, is performed with freshly cultured strains. The aim of this study was to examine the behavior of E. coli O157:H7 MB3885 under starvation stress in water used for overhead irrigation in the greenhouse and the consequence on its subsequent ability to attach to butterhead lettuce leaves. E. coli O157:H7 MB3885 was starvation stressed by introducing it at ±7.5 log CFU/ml into phosphate-buffered saline (PBS), sterile distilled water (SDW), or IW. The suspensions were stored at 4 or 20°C and were used after 0, 2, and 6 days for an attachment assay on butterhead lettuce. E. coli O157:H7 MB3885 levels were determined by plating method and live and dead quantitative PCR technique. A decrease in plate counts, an indicator of stress, was observed for most of the conditions, whereas a die-off, as revealed by the live and dead quantitative PCR data, was only observed in 1W stored at 20°C. Overall, stress appeared to be highest in IW and lowest in PBS. The stressed cells were still able to recover, even at 4°C, and to attach to the lettuce. Furthermore, our results show that standard laboratory solutions such as PBS and SDW may not be the best to simulate stressed cells in IW, in which the bacteria may behave significantly differently. [ABSTRACT FROM AUTHOR]

A previous multidisciplinary study indicated that gliotoxin-producing Aspergillus fumigatus Fresen. isolates from silage commodities mostly belonged to its variant A. fumigatus var. ellipticus Raper & Fennell. Sequence analysis revealed the presence of a single nucleotide polymorphism at five positions in a fragment of the rodA gene (coding for a hydrophobin rodletA protein) between Aspergillus fumigatus var. fumigatus and Aspergillus fumigatus var. ellipticus. A method was developed to distinguish these two types of isolates based on restriction analysis of this rodA gene fragment using the Hinf I restriction enzyme. In addition, in silico analysis of 113 rodA gene fragments retrieved from Gen Bank was performed and confirmed the suitability of this method. In conclusion, the method developed in this study allows easy distinction between A. fumigatus var. fumigatus and its variant ellipticus. In combination with the earlier developed PCR-restriction fragment length polymorphism method of Staab et al. (2009, J Clin Microbiol 47: 2079), this method is part of a sequencing-independent identification scheme that allows for rapid distinction between similar species/variants within Aspergillus section Fumigati, specifically A. fumigatus, A. fumigatus var. ellipticus, Aspergillus lentulus Balajee & K. A. Marr, Neosartorya pseudofischeri S. W. Peterson and Neosartorya udagawae Y. Horie, Miyaji & Nishim. [ABSTRACT FROM AUTHOR]

Introduction: Recent studies demonstrated that the gut microbiome of Parkinson's Disease (PD) patients differs from that of age-matched healthy controls. Notably less butyrate-producing bacteria and low mucosal and fecal short chain fatty acid (SCFA) concentrations were found in PD patients. SCFA play a role in the interplay of health and disease: SCFA butyrate improves colon motility, protects the colonic epithelium and reduces inflammation. Administration of butyrate in animal models of PD improved motor impairment and dopamine deficiency and reduced early mortality. We hypothesize that certain orally supplemented dietary fibers can stimulate butyrate production in the colon of Parkinson's patients, and consequently can improve the motor impairment and their quality of life. This hypothesis still requires a step-wise approach. Our objective is to investigate the effect of different types of dietary fiber on the gut microbiota and SCFA production in PD patients and healthy elderly. Material and methods: PD patients and healthy controls (HC) were selected based on age (55–70 years old) and BMI (18.5 -25 kg/m2). For PD patients the Hoehn and Yahr score (I – III) was added to this selection. The effect of inulin varying in degree of polymerization (DP) (average DP ~10 vs. average DP ~23) on the SCFA production was evaluated by ex vivo fermentation experiments with fecal samples of PD patients and HC. Inulin (1% w/v) was incubated in small-scale batch fermentations for 24 h at 37°C in anaerobic conditions. SCFA production was analyzed by solid phase micro-extraction capillary gas chromatography-mass spectrometry detection (SPME-cGS-MS). The clostridia clusters IV and XIVa were quantified through 16s qPCR. Results and discussion: Short chain (Sc) and long chain(Lc) inulin fermentation resulted in a mean total SCFA increase of respectively 490.3 ± 128.2μmol/ml and 384.3 ± 85.9μmol/ml in HC (n = 7) and 453.9 ± 99.2μmol/ml and 402.9μmol/ml ± 84.1μmol/ml in PD patients (n = 3). Sc inulin fermentation increased butyrate production with 200.0μg/ml ± 46.2μmol/ml in HC and 119.8 ± 94.4μg/ml in PD patients (p = 0.09). Lc inulin fermentation increased butyrate production with 174.9μmol/ml ± 82.2μmol/ml and 113.3μmol/ml ± 21.2μmol/ml in HC and PD patients, respectively (p = 0.25). Large variation between samples was observed in PD patients. Conclusion: Although sample size is relatively small and data is still collected, we can conclude that both Sc and Lc inulin increase total SCFA and butyrate production in HC and PD patients. This ex vivo study shows that stimulation of the butyrate production is still possible in PD patients and could be beneficial. [ABSTRACT FROM AUTHOR]

Freshly caught brown shrimp (Crangon crangon) are prone to rapid degradation after death. Freezing the unprocessed shrimp shortly after catch provides a possible solution to maintain product quality until further processing. In this study, Shrimp were frozen under three conditions (individually frozen, vacuum packed or glazed), either directly at −20°C or deep frozen at −50°C for three hours and subsequently stored at −20°C. A trained sensory panel assessed the organoleptic quality of brown shrimp that were cooked after 2 and 4 months of raw-frozen storage. Shrimp cooked under the same conditions immediately after the catch, then stored at −20 for maximum 1 month were used as reference. The quality of the frozen shrimp was also visually evaluated after one year. The individually frozen shrimp remained closest to the reference samples in terms of colour and odour when stored at −20°C, and closest to the reference for taste when initially frozen at −50°C. Vacuum-packed shrimp scored less well and glazed samples were omitted from the experiments beyond 2 months of storage due to visual deterioration. In conclusion frozen storage of raw shrimp is possible for short periods up to 4 months, albeit with perceivable changes in organoleptic properties of the final cooked product. [ABSTRACT FROM AUTHOR]

Heat-induced color changes of crustaceans are commonly described as the release of astaxanthin. In this study on Crangon crangon , it was found that astaxanthin plays a minor role in the (dis)coloration. By LC-HRMS, two polar, process dependent pigments were found. One pigment was identified as riboflavin and one as drosopterin (level-2 certainty). Thermal treatments had highest effect on drosopterin concentration changes and were chosen as indicator for a kinetic study of heat-induced color changes. The kinetic data fitted a consecutive step model ( r 2  = 0.971), including a first step in which drosopterin was released ( k d,85°C  = 0.95 ± 0.09 min −1 ; Ea d  = 105 ± 4 kJ/mol) and a second step where drosopterin is degraded ( k b,85°C  = 0.02 ± 0.002 min −1 ; Ea b =  190 ± 15 kJ/mol). The kinetic model shows that shrimp should be heated at lower temperatures (<80 °C) than the heating temperatures used by fishermen (86–101 °C), creating opportunities for quality optimization. Therefore, this study delivers essential information needed in a comprehensive quality optimization study of the cooked brown shrimp. [ABSTRACT FROM AUTHOR]

This study was performed to comprehensively reveal the composition of the microbial community of commercially cooked and machine peeled brown shrimp ( Crangon crangon ), packaged and stored under modified atmosphere without added preservatives. Three independent experiments, using both culture-dependent and culture-independent methods, were conducted over an entire shrimp season. Initial total aerobic psychrotrophic bacterial counts (APC) were relatively high on several general media ranging between 5.4 and 6.4 log cfu g −1 . After 7 days of storage at 4 °C, samples were considered microbiologically spoiled with no apparent difference in APC between samples from different periods. The dominant microbiota present after 7 days of storage was assessed by (GTG) 5 analysis of selected colonies and 16S rRNA gene sequence analysis. The dominant organism on general media was Arthrobacter bergerei , whereas on more selective media Shewanella putrefaciens , Brochothrix thermosphacta and Vagococcus salmoninarum were most abundant. Culture-independent denaturant gradient gel electrophoresis (DGGE) and Illumina next generation sequencing revealed Carnobacterium as a dominant genus at day 7 throughout the year, together with members of Shewanella and Psychrobacter . The differences in relative abundance of dominant genera between different months also indicated a possible seasonal influence on the microbial community. It could be concluded that the same major groups of spoilage bacteria were retrieved by culture dependent and independent approaches, but their relative abundance differed. [ABSTRACT FROM AUTHOR]

Chocolate confectionery fillings are generally regarded as microbiologically stable. The stability of these fillings is largely due to the general practice of adding either alcohol or preservatives. Consumer demands are now stimulating producers to move away from adding alcohol or other preservatives to their confectionery fillings and instead to search for innovative formulations. Such changes in composition can influence the shelf life of the product and may lead to spoilage by xerophilic fungi. The aim of this study was to test whether the production environment of Belgian chocolate confectionery factories and common ingredients of chocolate confectioneries could be potential sources of contamination with xerophilic fungal species. In the factory environment, the general and strictly xerophilic fungal spore load was determined using an RCS Air Sampler device in combination with DG18 and MY50G medium, respectively. Four basic ingredients of chocolate confectionery fillings were also examined for fungal spore levels using a direct plating technique. Detected fungi were identified to species level by a combination of morphological characterization and sequence analysis. Results indicated a general fungal spore load in the range of 50–250 colony forming units per cubic meter of air (CFU/m 3 air) and a more strict xerophilic spore load below 50 CFU/m 3 air. These results indicate rather low levels of fungal spores present in the factory environment. The most prevalent fungi in the factory environment were identified as Penicillium spp., particularly Penicillium brevicompactum . Examination of the basic ingredients of confectionery fillings revealed nuts to be the most likely potential source of direct contamination. In nuts, the most prevalent fungal species identified were Eurotium , particularly Eurotium repens . [ABSTRACT FROM AUTHOR]

Abstract: The dominant microbiota of brown shrimp (Crangon crangon) were systematically identified during storage under different conditions. Freshly caught shrimp were processed on board the fishing vessel under the best possible hygienic conditions (IDEAL), unpeeled and manually (sterile) peeled, then stored on ice and at 7.5 °C until microbiologically spoiled. Results were compared with industrially processed (INDUSTRIAL) shrimp. Isolates grown on various media were identified by 16S rRNA and gyrB gene sequencing. We examined the total microbiota and microbial population shifts of shrimp under various storage conditions using denaturant gradient gel electrophoresis (DGGE). The microbiota differed somewhat during storage and among the various storage conditions; however, members of the genera Psychrobacter and Pseudoalteromonas were found to dominate the microbiota of all shrimp samples regardless of processing procedures or storage conditions. Most isolates could be identified by gyrB gene sequencing as Psychrobacter immobilis or Psychrobacter cibarius. Also Pseudoalteromonas nigrifaciens, Pseudoalteromonas elyakovii or Pseudoalteromonas paragorgicola dominated the microbiota of brown shrimp during storage. Also species from the genera Planocuccus, Exiguobacterium, Carnobacterium, Pseudomonas, Chryseobacterium and Staphylococcus were detected during storage of brown shrimp. Culture-dependent and culture-independent DGGE analysis produced different results in band patterns. Both methods are therefore required to accurately identify the microbiota and bacterial population shifts on seafood during storage. [Copyright &y& Elsevier]

In any research field, data access and data integration are major challenges that even large, well-established consortia face. Although data sharing initiatives are increasing, joint data analyses on nutrition and microbiomics in health and disease are still scarce. We aimed to identify observational studies with data on nutrition and gut microbiome composition from the Intestinal Microbiomics (INTIMIC) Knowledge Platform following the findable, accessible, interoperable, and reusable (FAIR) principles. An adapted template from the European Nutritional Phenotype Assessment and Data Sharing Initiative (ENPADASI) consortium was used to collect microbiome-specific information and other related factors. In total, 23 studies (17 longitudinal and 6 cross-sectional) were identified from Italy (7), Germany (6), Netherlands (3), Spain (2), Belgium (1), and France (1) or multiple countries (3). Of these, 21 studies collected information on both dietary intake (24 h dietary recall, food frequency questionnaire (FFQ), or Food Records) and gut microbiome. All studies collected stool samples. The most often used sequencing platform was Illumina MiSeq, and the preferred hypervariable regions of the 16S rRNA gene were V3-V4 or V4. The combination of datasets will allow for sufficiently powered investigations to increase the knowledge and understanding of the relationship between food and gut microbiome in health and disease.

Background and Aims: Dietary management, as an adjuvant therapy in Parkinson's disease (PD), provides clear benefits to patients. However, baseline information about the usual dietary intake of Parkinson's patients is lacking. Methods: We conducted an observational cross-sectional study, investigating the dietary intake in Belgian PD patients, as well as their medication use and knowledge of possible food-drug interactions. A dietary record of 2 non-consecutive days, allowing the calculation of usual intake, was used. Medication use and knowledge of food-drug interactions were investigated using a self-administered questionnaire. Results: The nutrient (both macro and micro) intake in this study was similar to the dietary pattern of the general Belgian population. However, results showed that the PD population had a high dietary fiber intake of 26.2 ± 7.7 g/day, which is in line with the recommended intake. The majority of the PD patients had an inadequate intake of vitamin D and iron (respectively, 55.9 and 76.5% of all participants). When looking into the knowledge about food-drug interactions, the majority of the PD patients claimed to be aware of the food-drug interaction between dietary proteins and levodopa. However, only 18.2% of the patients took all doses of levodopa out of meals. Conclusion: Our results show that monitoring of dietary intake in PD patients is of importance to detect possible micronutrient insufficiencies. Patients should receive professional guidance in optimizing their diet to accommodate for different complaints inherent to PD, including constipation. Furthermore, the knowledge of patients regarding the importance of correct medication intake should be improved., (Copyright © 2020 Baert, Matthys, Mellaerts, Lemaître, Vlaemynck and Foulon.)

The European brown shrimp Crangon crangon is an abundant and commercially important species in the North Sea. Currently, there is interest in landing live shrimp to provide fresh animals for a growing market in live brown shrimp. During 4 survival studies between 2014 and 2016, shrimp were collected from commercial trawlers and maintained alive in off-shore facilities. From Day 1 onwards, a minority of shrimp (~2.24%) developed a white discoloration of the abdominal muscles and a depigmentation of the distal part of the abdomen, along with paralysis of the affected tissues and appendages. As the symptoms progressed, a circumferential blackish delineation appeared, creating a distinct boundary between healthy and necrotic tissue. Affected shrimp survived up to 3 wk, although in several animals the distal part of the tail was completely lost. Histological and electron microscopical examination confirmed the myonecrosis. A secondary bacterial invasion of the necrotic muscle was observed in some animals. RT-PCR for infectious myonecrosis virus was negative. The condition appears not to be contagious, based on the feeding of healthy shrimp with necrotic tissue of affected shrimp. Based on these observations, a mechanical cause inflicted during the catching process is proposed.

The survival of Salmonella enterica serovar Thompson and Escherichia coli O157 was investigated on growing butterhead lettuce plants in the plant-growth chamber and greenhouse. All inoculation tests were made under conditions that approximate the greenhouse conditions for butterhead lettuce cultivation in Flanders (Belgium). The survival and proliferation of the pathogens on the leaves was determined at days 0, 4, and 8 after inoculation using standard plating techniques on selective medium. In the growth chamber, the extent to which both pathogens were able to multiply on the lettuce leaves was influenced by crop stage and leaf age. On young plants, the older leaves supported pathogen survival better. On nearly mature plants, pathogen population sizes were significantly higher on the old and young leaves compared with middle-aged leaves (p<0.001). In the greenhouse, the environmental regimen with high fluctuations in temperature and relative humidity was less conducive to the survival of E. coli O157, though its survival on nearly mature lettuce was enhanced by overhead irrigation. The moist conditions between the folded inner leaves are likely contributing to the survival of enteric pathogens in the lettuce head. Butterhead lettuce grown in greenhouses with a sprinkle irrigation system may present a potential health hazard when contaminated near harvest. Experimental design (growth chamber versus greenhouse) largely influences enteric pathogen behavior on growing lettuce plants.

A multianalyte method was developed to identify and quantitate 26 mycotoxins simultaneously in maize silage by means of ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). The extraction and cleanup procedure consists of two extraction steps followed by purification on a Waters Oasis HLB column. The method developed was validated with the requirements of Commission Decision 2002/657/EC taken into account. The limit of detection and quantitation ranges were 5-348 and 11-695 ng/g, respectively. Apparent recovery varied between 61 and 116%, whereas repeatability and reproducibility were within the ranges of 3-45 and 5-49%, respectively. The method developed was successfully applied for maize silage samples taken at the cutting surface and 1 m behind that surface. Mainly Fusarium toxins (beauvericin, deoxynivalenol, enniatins, fumonisins, fusaric acid, and zearalenone) were detected, but postharvest toxins such as mycophenolic acid and roquefortine C were identified as well.

This study is a comparison of the isolation frequency of Listeria spp. and Listeria monocytogenes from selected naturally contaminated dairy products, especially soft smear-ripened cheeses from raw milk and samples of feces and rinse samples from the udder taken on the farm, by using an enrichment broth (EB) recommended by the International Dairy Federation and the U.S. Food and Drug Administration (IDF and FDA) or Fraser broth as the selective enrichment. Detection and identification were carried out according to the IDF protocols and a polymerase chain reaction technique. Listeria spp. were detected in 39.8% of the 570 samples while 15.3% were positive for L. monocytogenes . For cheese and curd samples, Fraser enrichment broth gave a statistically significant higher recovery for all Listeria spp. (26 to 21 %) as well as for L. monocytogenes in particular (9 to 1.4%). For raw milk and samples taken from feces and the udder rinse no significant difference was found between EB and Fraser broth. A combination of both enrichments resulted in an increase of recovery over all matrices by 15%.

A multiplex polymerase chain reaction (PCR) method for the identification of Listeria spp. and Listeria monocytogenes has been developed. For the identification of Listeria spp. two specific primers were derived from the 16S rRNA sequence. For the identification of Listeria monocytogenes specific primers were derived from the gene sequence of the invasion-associated protein. The two amplified DNA fragments, respectively 1003 bp and 593 bp, were separated by agarose electrophoresis. The results obtained by the multiplex PCR method were in agreement with those obtained by the classical bacteriological method for the 64 dairy samples with presumptive positives.