Food Microbiology for Cheese and E coli - myassignmenthelp.com

Question: Discuss about theFood Microbiology for Cheese and E coliContamination. Answer: Microbiology of E coli E coli is a gram positive facultative anaerobic bacteria, which is found in the lower intestine of living organisms. E coli have certain serotypes which causes serious harm in the hosts and is responsible for food poisoning. E coli contamination has been associated to products produces in large scale and has led to food recalls due to the contamination already caused, (Vogit Dippold, 2005). Normally there are strains of E Coli which are harmless, they are referred to as normal flora and produce vitamin k2 in their hosts, (Haudault et al, 2001), and is essential in preventing colonization process in the intestines. The genesis of E Coli is from faecal matter and is expelled from the environment whereby it causes contamination. The bacteria nourishes well in faecal matter for a period of 3 days, (Russell Javis, 2001). Thus E coli is attributed to many disease which include cholecystisis, bacteraemia, urinary tract infections among other diseases. Clinical presentation of E Coli E coli being a gram negative anaerobic makes ATP and at the same time switch to fermentation in the absence of oxygen. They exist in the intestines of humans and animals. Harmful E Coli are often pathogenic and can cause illness through causing diarrhoea or illness outside the intestinal path. Diarrhoea causing E coli can be transmitted in water or food or through contact with animals or people. The Shiga toxin producing E Coli or Verocytotoxin producing E Coli is the most common heard type of infection and has been associated with food borne outbreaks. The toxin referred to shiga causes damages the intestines linings. The bad strain identified as O157:H7 can make people very sick. It is associated with abdominal; pains, cramps and blood in the diarrheal flow. At times it is responsible for acute kidney failure among children. Further it is associated with bleeding, confusion, seizures or bleeding. Cheese and E coli contamination Raw milk has been found to contain various germs such as the bacteria, viruses and paracistes.raw milk has not yet undergone pasteurization that is heated to specific temperature for set amount of time in order to destroy harmful germs. Thus raw milk is unpasteurized and can contain harmful germs which include campylobacteria, E Coli, Listeria and Slamonnela, (Mathews et al., 2006). Thus cheese can cause E Coli due to the raw product of which is milk which is not pasteurized. Thus cheese from unpasteurized milk cause the E coli contamination if the bacteria strains are present in the milk, thus is a risk factor for shiga toxins, (Lejeune et al.,2001). Critical control points of cheese production include raw milk obtained from the animals. The six steps in cheese production include acidification, coagulation, curd and whey, salting, shaping and ripening. The critical steps which can bring contamination include acidification and coagulation steps. Primary and Secondary infections of E Coli E coli can be contaminated in other substances like water. Contact with water from a person who has E Coli could affect and have an impact on infection. Further these individuals could have had contact from one another especially from infected individuals, (Williams et al, 2005). Primary infections of E Coli include intake of untreated milk that is if one consume unpasteurized milk, intake of fruits and vegetables washed using contaminated water, consumption of her foods and beverages which might be contaminated. Secondary infection can entail drinking water which is contaminated, contact from infected persons or contact from animals already contaminated with the bacteria. Other indirect sources include the use of chopping board that has uncooked meant and contact with raw foods like salad. E Coli O157 PT21/28 E Coli O157 is common name which means shared by cattle and it is the main reservoir of human causing infections. The PT refers to Phage type 21/28 as a subtype of E coli. The PT refers to the cases upon diagnosis and classification which refers to 21 cases in 28 disease. It is used to describe the disease further and give a more elaborate meaning. Identification of E Coli O157, is arrived at using the latex reagents which include O157 antibody coated latex and control latex. The isolation process being undertaken in O157 agglutination is identified through biochemical means of confirmation, (Kruger et al., 2006). Lab confirmation and determination has to utilise with patients who present diarrhoea. The stool specimens include whole, stool, swabs. With this approach specimens should be taken immediately, (Lindstedt et al., 2004). MLVA profiling of O157 Multi locus variable number tandem repat analysis is an established technique, which is established under the sub typing and getting the genetic diversity of STEC. It is an established technique to sub type E Coli O157, MLVA is a PCR based sub type method that is used to discriminate the strains of different of bacteria based on the tandems, (LLucchesi et al., 2006). The modern molecular bacterial sequencing has been utilised under polymorophic molecular markets such as the Varibelk Number Tandem Repeats or the MLVA in a rapid and specific way to discriminate on the different serotype using the PCR Amplification tool, (Murphy et al., 2008). Linking evidence The cheese being made in Astone market could be linked to E Colli infection, as it was observed to be common in the production process. The results obtained shows that E coli bacteria could have potential systemic infection and contaminate the final products. This evidence can be supported with the fact that cheese is produced from raw milk which could be a direct linked for E Colli contamination. Thus is supported with the 26 cases of same strain being identified among patients. Reference Hudault, S., Guignot, J., Servin, A. L. (2001). Escherichia coli strains colonising the gastrointestinal tract protect germfree mice againstSalmonella typhimuriuminfection. Gut, 49(1), 47-55. Krger, A., Padola, N. L., Parma, A. E., Lucchesi, P. M. (2006). Intraserotype diversity among Argentinian verocytotoxigenic Escherichia coli detected by random amplified polymorphic DNA analysis. Journal of medical microbiology, 55(5), 545-549. LeJeune, J. T., Besser, T. E., Hancock, D. D. (2001). Cattle Water Troughs as Reservoirs ofEscherichia coli O157. Applied and Environmental Microbiology, 67(7), 3053-3057. Lindstedt B.A., Vardund T., L., Kapperud G. Multiple-locus variable-number tandem-repeats analysis of Escherichia coli O157 using PCR multiplexing and multicolored capillary electrophoresis. J Microbiol Methods. 2004;58:213222. Lucchesi, P. M., Krger, A., Parma, A. E. (2006). Distribution of saa gene variants in verocytotoxigenic Escherichia coli isolated from cattle and food. Research in microbiology, 157(3), 263-266. Matthews, L., Low, J. C., Gally, D. L., Pearce, M. C., Mellor, D. J., Heesterbeek, J. A. P., ... Gunn, G. J. (2006). Heterogeneous shedding of Escherichia coli O157 in cattle and its implications for control. Proceedings of the National Academy of Sciences of the United States of America, 103(3), 547-552. Murphy, M., Minihan, D., Buckley, J. F., O'Mahony, M., Whyte, P., Fanning, S. (2008). Multiple-locus variable number of tandem repeat analysis (MLVA) of Irish verocytotoxigenic Escherichia coli O157 from feedlot cattle: uncovering strain dissemination routes. BMC veterinary research, 4(1), 2. Russell, J. 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