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1 – 10 of 228Jodie Duggan and Carol A. Phillips
The numbers of reported cases of Listeria particularly Listeria monocytogenes in the UK have remained at a relatively low level since the peak which occurred in 1988‐1989. The…
Abstract
The numbers of reported cases of Listeria particularly Listeria monocytogenes in the UK have remained at a relatively low level since the peak which occurred in 1988‐1989. The majority of cases are sporadic and often the source of contamination is unknown. This study investigates the possibility that the home environment, which has previously been found to be the most common place of contamination for other bacteria, also provides a reservoir for human infection by Listeria monocytogenes and other Listeria spp.
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Will M. Waites, Christine E.R. Dodd and Kathy J. Bolton
The problems produced by changes in agricultural and foodmanufacturing practices, which have resulted in increases in reportedcases of food‐borne illness, are discussed in…
Abstract
The problems produced by changes in agricultural and food manufacturing practices, which have resulted in increases in reported cases of food‐borne illness, are discussed in relation to Salmonella, Campylobacter jejuni, Clostridium botulinum, Aeromonas hydrophila, Listeria monocytogenes and Yersinia enterocolitica. Those areas where further research is urgently required in order to understand and reduce food‐borne microbial illness are examined, and solutions proposed.
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The purpose of this paper is to investigate the effectiveness of NaOCl and KMnO4 at two levels in reducing the microbial load of coriander leaves.
Abstract
Purpose
The purpose of this paper is to investigate the effectiveness of NaOCl and KMnO4 at two levels in reducing the microbial load of coriander leaves.
Design/methodology/approach
Fresh coriander leaves procured from various markets were intensively sampled and administered to wash treatments with tap water and sanitizers at two levels. Hi media pre plated plates were used for determination of TPC (Total Plate Count), Staphylococcus aureus, Listeria, Salmonella, Shigella and coliforms.
Findings
Unwashed coriander leaves showed TPC beyond the acceptable limits of 105 CFU/g. Bulk washing (10 g sample dipped in 1 litre tap water for 5 minutes) did not significantly reduce TPC and any of the pathogens. TPC decreased significantly by 1 log cycle up on treatment with 200 ppm NaOCl and 100 ppm KMnO4. Staphylococcus aureus could be reduced more effectively with 100 ppm of KMnO4; Listeria monocytogenes and Salmonella showed significant reductions (P<0.05) using both sanitizers. Shigella decreased by more than 1 log cycle when treated with 100 ppm KMnO4.
Practical implications
Tap water is not sufficient to reduce the microbial load of fresh coriander. Use of 100 ppm NaOCl and 50 ppm KMnO4 may be considered to reduce the pathogenic load of coriander leaves. Since reduction of pathogenic load by 1 log cycle is insufficient, other means of disinfecting the raw produce need to be tested. Also, use of good irrigation practices and aseptic post harvest techniques cannot be ignored.
Originality/value
This is an original study, wherein use of sanitizers should be promoted in order to reduce the microbial load of coriander leaves.
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We are now very much aware of the hazards associated withsalmonella and listeria in foodstuffs. Newer methodologies are comparedwith conventional techniques for their rapid…
Abstract
We are now very much aware of the hazards associated with salmonella and listeria in foodstuffs. Newer methodologies are compared with conventional techniques for their rapid detection. Recent developments in culture media are discussed, as is a new rapid culture test kit for salmonella. Novel techniques such as ELISA, nucleic acid probes and flow cytometry are described, and a comparative assessment is made of reported findings. Nucleic acid probe and ELISA assays are considerably quicker than traditional culture techniques but they would benefit from increased sensitivity; they show inferior specificity with listeria and are still dependent on an enrichment stage. Recent DNA amplification techniques could provide a solution to the problem of poor probe sensitivity and allow the direct detection of pathogens from food samples. Flow cytometry may have the potential for high sensitivity and specificity and could be useful for on‐line monitoring in factories.
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Three events of significance to this country took place in 1899 – the British Food Journal was launched, Australia retained the Ashes, and the Boer War hostilities commenced. If…
Abstract
Three events of significance to this country took place in 1899 – the British Food Journal was launched, Australia retained the Ashes, and the Boer War hostilities commenced. If challenged on the order of their importance, cricketers and Empire‐builders may be excused their preference. However, looking at it purely from the standpoint of pro bono publico, the dispassionate observer must surely opt for the birth of a certain publication as being ultimately the most beneficial of the three.
Karmen Godic Torkar, Andrej Kirbiš, Stanka Vadnjal, Majda Biasizzo, An Galicic and Mojca Jevšnik
The purpose of this paper is to study the microbiological quality of raw milk delivered by 17 vending machines (VM) owned by different Slovenian milk producers.
Abstract
Purpose
The purpose of this paper is to study the microbiological quality of raw milk delivered by 17 vending machines (VM) owned by different Slovenian milk producers.
Design/methodology/approach
For the determination of hygiene-technical conditions of VM, an observation list that included criteria for estimation of hygiene-technical suitability was made. A total of 51 milk samples were collected in three different seasons. The swabs and the cleaning liquid (eluates) of dispensing nozzles and chambers were also sampled. The main groups of microorganisms were determined by colony count technique according to international standards in all collected samples.
Findings
The aerobic colony count was higher than 100,000 CFU/mL in 20 (39.2 per cent) of milk samples. Its mean value was 4.8 log10 CFU/mL. The mean values of Enterobacteriaceae, psychrotrophic microorganisms, lipolytes, proteolytes, yeasts and moulds together, coagulase-positive staphylococci and somatic cell count were 3.3 log10 CFU/mL, 4.1 log10 CFU/mL, 3.2 log10 CFU/mL, 3.9 log10 CFU/mL, 2.2 log10 CFU/mL, 2.8 log10 CFU/mL and 5.3 log10 cells/mL, respectively. E. coli was found in 33.3 per cent of milk samples, while Listeria monocytogenes and antibiotics were not detected. The inner surface contamination of the dispensing nozzles and chambers was estimated in the range from 1.8 log10 CFU to 6.0 log10 CFU/cm2. The presence of detergents and disinfectants in supply valve eluates was determined in more than one-third of the samples. The hygienic-technical conditions of observed VM show some deviations from specified hygienic-technical requirements which could influence the safety of raw milk.
Research limitations/implications
The data about construction and the cleaning practice of VM, included in the experiment, were not available during the inspection facility.
Originality/value
In the paper the pathogenic and also the spoilage microorganisms in milk in the combination with hygienic conditions of inside surfaces of VM were studied.
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Despite increased education and legislation to raise standards of hygiene in all aspects of food handling, a definite increase is reported in food‐borne infections and…
Abstract
Despite increased education and legislation to raise standards of hygiene in all aspects of food handling, a definite increase is reported in food‐borne infections and intoxications in the UK. The main bacteria are examined here and, since it is envisaged that the number of reported cases is likely to increase still further in future years, recommendations are put forward which are aimed at improved education rather than legislation.
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Lochan Singh and Vijay Singh Sharanagat
Nature and occurrence of food-borne pathogens in raw and processed food products evolved greatly in the past few years due to new modes of transmission and resistance build-up…
Abstract
Purpose
Nature and occurrence of food-borne pathogens in raw and processed food products evolved greatly in the past few years due to new modes of transmission and resistance build-up against sundry micro-/macro-environmental conditions. Assurance of food health and safety thus gained immense importance, for which bio-sensing technology proved very promising in the detection and quantification of food-borne pathogens. Considering the importance, different studies have been performed, and different biosensors have been developed. This study aims to summarize the different biosensors used for the deduction of food-borne pathogens.
Design/methodology/approach
The present review highlights different biosensors developed apropos to food matrices, factors governing their selection, their potential and applicability. The paper discusses some related key challenges and constraints and also focuses on the needs and future research prospects in this field.
Findings
The shift in consumers’ and industries’ perceptions directed the further approach to achieve portable, user and environmental friendly biosensing techniques. Despite of these developments, it was still observed that the comparison among the different biosensors and their categories proved tedious on a single platform; since the food matrices tested, pathogen detected or diagnosed, time of detection, etc., varied greatly and very few products have been commercially launched. Conclusively, a challenge lies in front of food scientists and researchers to maintain pace and develop techniques for efficiently catering to the needs of the food industry.
Research limitations/implications
Biosensors deduction limit varied with the food matrix, type of organism, material of biosensors’ surface, etc. The food matrix itself consists of complex substances, and various types of food are available in nature. Considering the diversity of food there is a need to develop a universal biosensor that can be used for all the food matrices for a pathogen. Further research is needed to develop a pathogen-specific biosensor that can be used for all the food products that may have accuracy to eliminate the traditional method of deduction.
Originality/value
The present paper summarized and categorized the different types of biosensors developed for food-borne pathogens.
Graphical abstract
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Listeriosis in animals and humans has been known for over 60 years.Outbreaks in humans have been reported since 1951 but the importance offoodborne transmission has only been…
Abstract
Listeriosis in animals and humans has been known for over 60 years. Outbreaks in humans have been reported since 1951 but the importance of foodborne transmission has only been realised recently. Listeria monocytogenes is of concern to the food industry because of its ability to grow at refrigeration temperatures and the serious nature of listeriosis. Surveys have shown a widespread incidence of L. monocytogenes in foods and high numbers in certain foods. Hygienic practices in food production are being modified to reduce this incidence, and conditions to minimise the survival and growth of listeria in foods are being determined. Listeriosis is still a relatively rare disease and the majority of people may be resistant, or develop immunity to the bacterium. Because of the fact that a significant proportion of the population is likely to be vulnerable to infection, and the trend towards increased consumption of chilled foods which may have an extended shelf life, it is important to minimise the incidence of listeria in foods.
Investigates the conditions surrounding the spread of the bacteriumListeria monocytogenes and the implications for food safety,including cook‐chill food production, temperature…
Abstract
Investigates the conditions surrounding the spread of the bacterium Listeria monocytogenes and the implications for food safety, including cook‐chill food production, temperature, contamination and storage. Concludes that food can never be made entirely microbiologically safe but the risks can be minimized.
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