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D A Mossel

Publications and source records attributed to D A Mossel.

At least 55 records · Page 3Linked to original sources
PubMed1987

[Identification and prevention of meat poisoning].

In this contribution to a series 'Papers of Yesterday and Today' a retrospective review of developments in the identification and control of meat 'poisoning' defined as infections and intoxications following the ingestion of bacteriologically unsound meat and meat products is presented. Starting from two classical Dutch papers, viz. by H. J. H. Stempel (1891) and K. Hoefnagel (1899) illustrating the knowledge of meat 'poisoning' acquired in the nineties of the 19th century, developments in the field of bacteriological research on meats and the resulting efforts to manage meat 'poisoning' are summarised. Attention is paid to the role of Dutch veterinarians in investigations on the aetiology of meat infections resulting in the adoption of legal meat inspection in 1922 and the ensuing reduction in the occurrence of mass outbreaks of meat poisoning. However, despite marked improvement of the standard of hygiene in the food industry in general and expert monitoring of meat production lines by veterinarians in particular, infections and intoxications transmitted by meat and meat products are still quite prevalent. Essentially, their management can only be achieved by strict adherence to Good Manufacturing Practices (GMP) throughout animal husbandry, slaughter, distribution and storage, termed longitudinally integrated safety assurance. Professional monitoring by an up-to-date meat inspection system, however, continues to be indispensable in the prevention of food-borne infections and intoxications. Some recommendations are made for effective intervention in the infection cycle of food-transmitted pathogens originating from the high infection pressure on slaughter lines, resulting from contamination acquired at previous stages of the animal production chain.

Animals↗
PubMed1987

Integrated microbiological safety assurance and monitoring of food and drinking water. Professor Kampelmacher's contribution to postgraduate education in The Netherlands from the point of view of Veterinary Public Health.

The history of academic education in food microbiology and hygiene in the Netherlands has largely been written by Prof. Kampelmacher. The first contribution in this field dates from 1961, and suggested a new approach to teaching Veterinary Public Health. His later research led to the conclusion that intervention would be the only way to control the food-transmitted diseases originating from slaughter animals and poultry, particularly Salmonellosis. This intervention should take place at the beginning of the contamination cycle. In the 1970's, surveys showed that feed decontamination would no longer efficiently control the endemicity of Salmonellosis. The contamination cycles had become autonomous. Consequently, emphasis on terminal decontamination of food products was necessary. Besides his activities in teaching and research, Prof. Kampelmacher masterminded a modern view of the responsibilities of academic scientists. Moreover, he strongly promoted an interdisciplinary approach to scientific consultation and advice. In this respect, he has unfortunately not been successful in introducing radiation of dangerously contaminated food, having met strong opposition from various quarters. His efforts in multidisciplinary training and research programmes resulted in, among other things, fruitful cooperation between the Agricultural University at Wageningen and the Faculty of Veterinary Medicine at Utrecht University.

Education, Graduate↗
PubMed1986

[A small outbreak of salmonellosis caused by Bologna sausage].

Late in August 1985, seventeen subjects in the 3-40 year range contracted salmonellosis which was associated with the consumption of fermented pork sausage prepared by a butcher. The incubation period varied from 6 to 9 hours, the attack rate was a hundred per cent; there were no deaths or complications. The pH of the incriminated sausage was 5.7 (the pH of controls ranged from 4.5 to 5.0), and the aw was 0.99 (vs. 0.92-0.97 in the controls), a colony count of thermotrophic Enterobacteriaceae was 10(7) per 1 g, including c. 10(6) of Salmonella typhimurium, c. 10(3) Staphylococcus aureus and c. 10(4) cfu of Clostridium perfringes per 1 g. These outbreaks may be prevented by ensuring good practices during production and distribution, supported by monitoring line samples by determining the pH and aw and cfu assessment of Staphylococcus aureus and thermotrophic Enterobacteriaceae.

Adolescent↗
PubMed1986

The enumeration of thermotrophic types amongst the Enterobacteriaceae colonizing perishable foods.

A total of 41 pure cultures of Enterobacteriaceae, comprising 32 thermotrophic and nine psychrotrophic strains, pathogens or marker organisms, were examined for numbers of colony forming units obtained at 37 degrees and 42.5 degrees C (thermotrophs) and 30 degrees C (psychrotrophs), when surface-plated on a rich infusion agar and violet red bile agar. In addition 42 food and water samples, collected in a rural area of the Philippines, were examined by surface inoculating violet red bile AIPC (agar immersion plating and contact; 'dip') slides and incubating at 37 degrees and 42.5 degrees C. At 42.5 degrees C there was almost total recovery of the thermotrophic Enterobacteriaceae, whereas the psychrotrophic strains were completely suppressed. At 37 degrees C the psychrotrophs were only slightly inhibited. The Philippine foods, predominantly cooked meals, milk and drinking water, appeared to be significantly colonized by thermotrophic Enterobacteriaceae. It is concluded that incubation at 42.5 degrees C satisfactorily selects enteropathogenic and other enteric Enterobacteriaceae while suppressing the psychrotrophic types which are mainly of vegetable origin. It is emphasized that, regardless of the temperature used, a resuscitation procedure for Enterobacteriaceae populations that have incurred sublethal injury in food has to precede counts on or in the usual selective media.

Animals↗
PubMed1985

Lactic acid as a decontaminant in slaughter and processing procedures.

An attempt was made to interrelate the data obtained in experiments conducted by our Department along beef, veal and pig slaughter lines, using lactic acid (LA) for the decontamination of carcasses, cold and hot boned primal cuts, slaughter byproducts, and butcher's knives. First and foremost it was observed, that provided Good Manufacturing Practices are strictly followed, the microbial load of carcass surfaces will be substantially reduced. LA-decontamination may result in an additional reduction. Since in the early post-mortem period bacteria are not yet attached to the meat surface, LA-decontamination should preferably be applied to the hot carcass. It was demonstrated that, dependent on mode and duration of application, LA sprays not exceeding 1% v/v (beef), 1.25% v/v (veal) and 1.5% v/v (pork) resulted in acceptable carcass colour scores. Blood spots, which are particularly prone to discolouration by lactic acid application, should be removed at an early post-mortem stage e.g. by strong showering. The difference in surface pH between LA-treated and control carcasses disappeared within 72 hours post-mortem. Veal longissimus chops treated with LA solutions up to 2% v/v were not identified by a consumer taste panel as significantly different from controls. The 'immediate' bactericidal effect of LA-decontamination for beef, veal and pig carcasses, as well as for pig liver and veal brain, amounted to approximately 1.5 log cycles for the aerobic colony counts, strongly dependent on substrate and conditions of decontamination. In addition, a 'delayed' bacteriostatic effect was observed during storage, which is probably the result of a prolonged lag phase of acid-injured micro-organisms surviving lactic acid decontamination.(ABSTRACT TRUNCATED AT 250 WORDS)

Disinfection↗
PubMed1984

A centenary of academic and less learned food microbiology. Pitfalls of the past and promises for the future.

A review is presented of the development of Food Microbiology from its roots in different disciplines - including human and animal medicine, general microbiology, agricultural science and food chemistry - to an autonomous science with the main vocation to provide the knowledge allowing providing food that is wholesome, of high quality and acceptable in the microbiological sense. This evolution entailed a change in approach from mere, and often rather primitive inspection of end-products to intervention by (i) identification of hazard points ("critical points" or CPs) by ecological studies; (ii) elimination of CPs by elaboration of Good Manufacturing and Distribution Practices (GMPs); (iii) validation of GMPs by monitoring production lines and final products at point of sale and gauging the results by Risk Analysis. It is emphasized, that although advanced and ecologically sound techniques have become available, it will still require extensive education and training at all levels before the scientific advances outlined in this review will have been fully integrated in day-to-day food production and catering in developed as well developing areas of the world. Interdisciplinary instruction and co-operation cannot be missed in attempts to reach this goal.

Bacterial Infections↗
PubMed1984

A note on catalase enhanced recovery of acid injured cells of gram negative bacteria and its consequences for the assessment of the lethality of L-lactic acid decontamination of raw meat surfaces.

Addition of catalase (150 units/ml) to a rich infusion agar used for solid medium repair of acid injured pathogenic Enterobacteriaceae increased the recovery of such populations by 1-2 log cycles entailing an equal size reduction in the true lethality of this mode of processing for safety.

Animals↗
PubMed1983

Quality assurance of selective culture media for bacteria, moulds and yeasts: an attempt at standardization at the international level.

To facilitate monitoring of culture media, a simple quantitative streaking technique, implying ever-decreasing numbers of colony-forming units per surface area, as in spiral plating, was developed. The procedure evaluates, in quantitative terms, the ability of media (1) to support the formation of colonies by organisms that it was designed to grow and (2) to resist colonization by organisms that it is expected to suppress. The procedure was therefore termed ecometric evaluation. The ecometric results appeared to agree well with observations made on productivity and selectivity of the media studied during routine examination of specimens. These encouraging results prompted further, rigorous standardization of ecometry. A template was developed to standardize inoculation and the depth of the agar was controlled to within +/- 10%. Finally the attributes of the inocula used were accurately defined. The standardized ecometric technique has been found useful for the following purposes: (1) to assess the practical significance of the inhibitory effect of gentamicin observed in some moulds and yeasts (this was solved by replacing poorer basal media by one particular richer modification, viz, yeast morphology agar); (2) the development of a blood-free selective enumeration medium for Campylobacter jejuni, i.e. sulphide iron motility agar plus the combination of antibiotics suggested by Skirrow (1977); and (3) verification of the absence of antimicrobial activity of enzyme preparations, e.g. catalase, used in culture media to remedy sublethal damage in certain groups of bacteria. Ecometric evaluation can now be recommended for (1) routine monitoring of consignments of dehydrated or ready-to-use, purchased media; and (2) in-house checking of the functioning of medium preparation departments. Only occasionally is it necessary to use conventional counting techniques to confirm the results.

Bacteria↗
PubMed1983

Machakos project studies agents affecting health of mother and child in a rural area of Kenya. XXIII bacterial contamination of foods commonly eaten by young children in Machakos, Kenya.

A simplified method, the Agar Immersion Plating and Contact (AIPC) slide technique was applied for the bacteriological examination of children's dishes and drinking water in Machakos District, Kenya. A total of 214 samples, collected from 106 households, were examined for degree of colonization by Enterobacteriaceae (E) and Staph. aureus (ST). Fourty four percent of the dishes and two percent of the water samples were unsafe with respect to Enterobacteriaceae. In 12% of the dishes and none of the water samples Staph. aureus occurred at levels above the threshold of acceptability. Colonization increased with storage time. Implications of these results in relation to diarrhoea morbidity patterns among young children are being investigated elsewhere.

Child, Preschool↗
PubMed1982

Selective isolation and enumeration of low numbers of Staphylococcus aureus by a procedure that relies on elevated-temperature culturing.

A procedure for the selective detection of Staphylococcus aureus was elaborated, consisting of three parts: (i) enrichment in liquid Baird-Parker medium; (ii) isolation on Baird-Parker agar incubated at 43 degrees C, and (iii) confirmation by means of the test for thermostable nuclease. Elevated-temperature incubation of Baird-Parker medium did not make it inhibitory to cells stressed by heat treatment or osmotic shock.

Bacteriological Techniques↗