Camembert Contaminated By Staphylococcus: Microbial Risk Assessment

Hazard Identification

Discuss About The Camembert Contaminated By Staphylococcus?

Staphylococcus aureus is a gram-positive cocci having a round shape (Foster, Geoghegan, Ganesh & Höök, 2014). It proliferates at optimum environmental condition, like 37-degree centrigrade and 7 pH. It is best grown in the presence of oxygen but is also capable of multiplying aneorobically (Chatterjee et al., 2013). Staphylococcus aureus produce enterotoxin that is resistant to heat and independent of oxygen (Berube & Wardenburg, 2013). Human is the main reservoir of Staphylococcus aureus like in nose and in respiratory tract. Human contamination of the food leads to the multiplication of the S. aureus over the food leading to food poisoning (Wattinger, Stephan, Layer & Johler, 2012). The enterotoxin produced by S. aureus causes intestinal inflammation and is common in both children and adults. S. aureus are extremely potent, presence of 1.0 µg of toxin or less than that in the contaminated food is capable enough to generate hypersensitivity response. S. aureus cannot compete with other bacteria and hence fails to thrive over the raw food materials. Staphylococci thrive well in cooked foods. Among the cooked food, important ones are food, which are high in protein, sugar, and salt, low or slightly acid, or food with moist fillings (Bennett & Tallent, 2013). Camembert is mould-ripened cheese and is soft in conformity. Its high salt concentration (sodium chloride and potassium chloride) along with presence of milk make it more vulnerable to S. aureus attack (Lessard, Bélanger, St-Gelais & Labrie, 2012). The following report will shed light on the microbial risk assessment for the safety of camembert cheese contaminated by Staphylococcus aureus.

This is the first and the foremost step towards the microbial risk assessment. It aims to identify the microorganism that has contaminated food. It is via identification of the microorganism that the proper prevention plan will be designed (Buchanan, Cole, Lammerding, Clarke, Schothorst & Roberts, 1998). The concerned hazards come in the form of diverse sources like raw materials used to the production of food, methods which are undertaken for the production of the food and the use of the food.

Name of the Ingredients	Use or Importance Save Time On Research and Writing Hire a Pro to Write You a 100% Plagiarism-Free Paper. Get My Paper
Cow’s or Buffaloes Milk	Principal raw material
Lactic acid (starter cultures)	Helps in flavor generation via processing the milk
Rennet (coagulating enzyme)	Used in cheese processing and for getting a soft surface
Sodium Chloride, Potassium Chloride	Used as salt
Water	For dilution
Rice, corn, potato flours and starches	Anti-caking agents
Bleaching powder	Food additives
Penicillium candidium and /or Penicillium camembertii and Penicillium caseicolum	Rind formation

Table: Ingredients Used for Camembert Cheese Production

(Source: Lessard, Bélanger, St-Gelais & Labrie, 2012)

Property	Intrinsic These are natural or inherent properties of food	Extrinsic These are environmental factors in which the food products are being kept
pH value: 5.1 to 5.9 this mildly acidic pH promotes bacterial growth	Temperature of storage: Short term storage of Camembert cheese occurs at 30 degree C and thus providing optimal temperature for bacterial growth
Moisture content: 0.93 to 0.98 facilitate the growth of the bacteria	Relative Humidity: Cheese are most and humid and hence promoting bacterial growth
Nutrient content: Rice, corn, potato flours and starches which are the principal source of carbohydrate	Presence of Microbial activity: Cheese is known for the presence of microbial activity due the process of fermentation undertaken
Anti-microbial constituent: Lactoferrin, conglutinin and lactoperoxidase system present in milk	Presence of gas: Ozone at times is used to preservation which facilities the bacterial growth
Biological Structure: Grooves of the cheese

Table: Intrinsic and Extrinsic Factors of Camembert cheese promoting bacterial growth

(Source: Lessard, Bélanger, St-Gelais & Labrie, 2012; Hickey, Sheehan, Wilkinson & Auty, 2015)

Question	Answer (Yes or No)	Outcome	Reference
1. Is the suspected pathogenic micro-organism present there in the raw materials used for the production?	Yes	Staphylococcus aureus is a gram-positive bacteria and facultative anaerobe by nature. It is a foodborne pathogen that can be easily isolated from dairy products and meat
If yes proceed to Question 2	If No Eliminate Organism form the List
2. Will the process involved in the production will eliminate the harmful micro-organism completely?	No	S.aureus has a wide range of incubation temperature ranging in between 7°C to 48.5°C, pH 4.2 to 9.3, and NaCl concentrations of 0 to 15% and hence it cannot be easily eliminated from the food during processing
If yes, eliminate the organism from the list	If no then proceed to Question 3
3. Will this pathogenic micro-organism will contaminate the food product after processing or the production is complete?	Yes
If yes then proceed to Question 4.	If no then eliminate the micro-organism from the list and proceed to question 4
4. Do the micro-organism has caused problem in the recent future or in the near past as a result of food contamination?	Yes	The first report on the food-borne disease arising out of the S.aureus was reported in Michigan (USA) in the year of 1884. This food poisoning event occurred as a result of consumption of S.aureus contaminated cheese. 10 years after this encounter, a family who has consumed eat of cow died out of vitullary fever ignited by the pathonegic presence of staphylococci. The first proof of S.aureus in food poisoning occurred in 1914 (Hennekinne et al., 2012).	(Hennekinne et al., 2012).
If yes, proceed to Question 5.	If no then eliminate the organism from the list
5. If the pathogen of concern has infection and toxinogenic properties?	Yes	S. aureus produced a wide range of toxins which are majorly aimed to evade the host immune response. Toxins like alpha toxins and phenol soluable modulin (PSM) toxins are produced by nearly all strains of S.aureus. The classical leukotoxins produced by S.aureus performs its toxic activities via receptor-mediated endocytosis. On the other hand, PSM lyse the host cell in a receptor independent manner	(Otto, 2014)
If toxic the proceed to question 6	S. aureus has been found infectious and hence enlisted under the potentially hazardous micro-organism and is added to the final list of proceeding
6. Do the micro-organism shows growth in the food?	Yes
Yes and added to the final list of risk profiling	If no then eliminate the micro-organism form the list

Table: Hazard Data Sources

Source: Created by Author

Figure: Food Contamination Arising out of S.aureus

Hazard Characterization

(Source: Hennekinne et al., 2012)

S.aureus produced enterotoxins. These enterotoxins caused inflammation in the intestinal track lining of the patient. However, such inflammations are seldom treated as fatal among the elders but if the same complications occur in children then fatality can be a chance.

The food poisoning caused by the S.aures via the I gestion of the contaminated cheese are mainly nausea followed by vomiting, abdominal cramp and as the condition becomes more severe, the symptom is manifested as diarrhea. Furthermore, some people are found reporting headaches, fever and sweating. The intensity of the symptoms depends on the amount of ingested food and immunogenic backup of the person or susceptibility of the individual towards the bacterial enterotoxin.

Estimated rate of hospitalization is 18% and the fatality rate is 0.02%. However, the adverse outcomes also depend on the amount of food ingested, the strength of the host immune response and the susceptibility of the individual towards the bacterial enterotoxins.

The enterotoxin of S.aureus is extremely potent, less than 1.0 µg of toxin in present in the contaminated food is sufficient to generate symptoms like diarrhea. This estimated minimal hazardous toxin level is easily achieved when the colonies of S. aureus exceed more than 105 colonies per gram. Limited numbers of S. aureus colonies in the food culture is not directly related to health hazard.

All the people are believed to fall under the risk group bracket of the S.aures inflammation. However, children are more frequently affected than the adults (The New Zealand Food Safety Authority, 2001)

The main aim of the exposure assessment under the microbial risk assessment is to ascertain the concentration of the bacteria (or its toxin) that is likely to be present in food (cheese) at the time of consumption (Buchanan, Cole, Lammerding, Clarke, Schothorst & Roberts, 1998).

Milk and its byproducts are the source of food borne diseases. It has frequently been implicated that S.aureus mastitis is a detrimental problem in diary industry and the infected animal may be responsible for the bulk contamination. Other sources of the bulk milk contamination are teat skin of the diary animals, milking equipment, the surrounding environment and the udder. The frequent contamination of the dairy product (milk) via S.aureus causes generation of bacterial enterotoxin. There are 18 serological types of the S.aureus and these enterotoxins are heat stable and resistant to proteolytic degradation by intestinal pepsin (Saadat, Fooladi, Shapouri, Hosseini & Khiabani, 2014).

Symptoms of the Disease

According to Kim et al. (2009), the constant relation between the toxin production and the number of the bacterial cell evaluated on the basis of a equation

Tox=0.9300751 × C − 6.662092

Here, Tox is the rate of toxin production expressed in the logarithm value (log ng ml−1) and C is the number of bacterial cells in the culture (log cfu ml−1).

The initial level of contamination of the raw material starts from the starter cultures of lactic acid. Lactic acid bacteria like lactobacilli and Leuconostoc citrovorum are not inhibitory to the growth of the S.aureus but only causes slight inhibitory effect on the enterotoxin. 

Growth of S.aureus is associated with protein-rich food and dairy products. The dairy products like cheese are complex matrices in comparison to broth. This comparison is done based on the total microbial content, salt, pH of the medium, availability of the nutrient, oxygen and optimum temperature. Generally, optimal growth of S. aureus is required for the production of enterotoxin. However, enterotoxin production is always not accompanied with the microbial growth. In a certain cases, the production of toxin has also been detected in the culture of non-replicating cells.

The production of Camembert cheese takes place at acidic pH due to the presence of Lactobacillus. This acidic pH or Low pH causes the subsequent induction of prophage multiplication. The multiplication of prophage leads to the increase in the sea expression of the bacteria. The prolonged sea expression is commonly observed during the boiling of milk. The transcription of phage-encoded virulence genes has been detected at an increased level upon prophage induction. The same has been demonstrated for Panton-Valentine leukocidin in S. aureus. As per the study of the transcriptomic approach of the virulent gene expression in a cheese matrix under the influence of Lactococcus lactis, the sea expression of the microbes was slightly increased under the action of the acidic environment produced by the lactic acid (Schelin, J., Wallin-Carlquist, Thorup Cohn, Lindqvist & Barker, 2011).

The sanitation controls are defined as an important element of the Food Safety Plans. It is a crucial requirement for all the food processors as legislated under the Food Safety Modernization Act. The end output of the process of sanitation control is high quality dairy products that are safe in terms of health and digestion. The process of sanitation initiates in the milking parlor and continues throughout the process of cheese processing until the product is safely packed inside the carton. Under the level of the sanitation, control there falls maintenance of the personal hygiene, proper handling of the equipments and the ingredients used for cheese production. The sanitization process in the cheese production also encompasses proper handling of the packaging material and proper packaging of the finished products. The degree of proper sanitization is also regulated in the fermentation room, storage areas and whole facility room. For the application of the sanitization process needs stringent consideration of certain factors like Pre-rinse procedure, wash, post rise(via acid), periodic application of the pesticides under proper concentration and maintenance of the proper chemical safety. All these sanitization protocols are observed under the Sanitation Standard Operating Procedures (SSOPs) (Dairy Product Manufacturers (4/95), 2017).

Likelihood of Adverse Outcomes

Other areas that fall under the sanitization process includes, surface of the equipments, utensils, packaging material, tables and the area of preparation and the surrounding environment.

However, in most of the cases, proper sanitization process like maintenance of the hand hygiene is not observed during the process of milk processing, the principal byproduct for cheese production and hence this lead to the generation of the bacterial contamination. The nasal carriage of the S.aureus is regarded as the principal driving force behind the bacterial infection. S.aureus is also present in the human skin and other soft tissues (Centre of Disease Control, 2017).

The occurrence of recontamination occurs when the pH of the overall mixture increases, moving it towards mildly acidic, promoting the growth of the S.aureus. The another step towards the occurrence of the recontamination occurs when the complex of solution arising out of the milk and the hey products is allowed to cool at 40 degree c, making the temperature condition optimal for the bacterial growth.

The Camembert cheese is produced via using milk as the principal raw material. The process of the production of the camembert cheese, complex that is formed in between casein and whey protein occurs at a temperature of 87°C. Here the raw materials are heated in high flame for constant 10 min. after heating step, there comes the step of cooling. The complex is allowed at cool down and the temperature is brought down at 40°C. After this, a certain percentage of yogurt culture along with a certain concentration of CaCl2 and suspension of Penicillium candidum culture and rennet were slowly added to the milk. The process of cheese ripening is done for a constant stretch of 20 days in the pre0defined ripening room at a temperature of about 10°C and the degree of humidity is maintained in between 90-95%. This humid condition increases the quality of the overall production. The total yield of the cheese is increased as a result of high total nitrogen utilization due to the formation of complex co-aggregates. These complex co-aggregates include nitrogen and whey products. The maximum changes occurs during the process of ripening of the milk proteins. The change is indicated via the extremely high value of the ripening coefficient or the maturity index. Towards the end of the process of 20 days’ ripening, the amount of soluble nitrogen content increases exponentially in comparison of what was at the beginning of the ripening process. The overall pH level of the cheese shows a permanent steep increase, turning from acidic to mildly acidic. The increase in the pH is attributed to the process of protein breakdown induced by the complex proteolytic system of Penicillium candidum (the fermenting agent) and via the process of lactic acid neutralization (Ma?ej, Jovanovi? & Denin, 2001).

The recommended storage instruction of the camembert cheese is at 35 to 45 degree Fahrenheit and at a high level of humidity.

Yes

Human

Yes

Staphylococcus aureus

Camembert Cheese

Figure: MRA Excel Model

(Source: Sea Food 360)

(Modified by the Author)

The risk of the microbial contamination in Camembert cheeses is high and the principal microbes found contaminating Camembert cheese is Staphylococcus aureus.

Conclusion              

Thus from the above discussion it can be concluded that Camembert chesses has a high risk of contamination via Staphylococcus aureus. The potential food safety issues arising out of the process of the manufacturing of Camembert cheese is the lack of the proper maintenance of the hand hygiene and sanitization of the external environment.   

References

Bennett, R. W., Hait, J. M., & Tallent, S. M. (2013). Staphylococcus aureus. Guide to Foodborne Pathogens, Second Edition, pp. 26-44.

Berube, B. J., & Wardenburg, J. B. (2013). Staphylococcus aureus α-toxin: nearly a century of intrigue. Toxins, 5(6), 1140-1166.

Buchanan, R. L., Cole, M., Lammerding, A. M., Clarke, I. R., Schothorst, M. V., & Roberts, T. A. (1998). Potential application of risk assessment techniques to microbiological issues related to international trade in food and food products. Journal of food protection (USA).

Center of Disease Control (2017). Retrieved 25 September 2017, from https://wwwnc.cdc.gov/eid/article/16/5/pdfs/09-0851.pdf

Chatterjee, S. S., Joo, H. S., Duong, A. C., Dieringer, T. D., Tan, V. Y., Song, Y., … & Otto, M. (2013). Essential Staphylococcus aureus toxin export system. Nature medicine, 19(3), 364-367.

Dairy Product Manufacturers (4/95). (2017). Fda.gov. Retrieved 25 September 2017, from https://www.fda.gov/iceci/inspections/inspectionguides/ucm074974.htm

Foster, T. J., Geoghegan, J. A., Ganesh, V. K., & Höök, M. (2014). Adhesion, invasion and evasion: the many functions of the surface proteins of Staphylococcus aureus. Nature reviews. Microbiology, vol. 12(1), pp. 49.

Hennekinne, J. A., De Buyser, M. L., & Dragacci, S. (2012). Staphylococcus aureus and its food poisoning toxins: characterization and outbreak investigation. FEMS microbiology reviews, vol. 36(4), pp. 815-836.

Hickey, C. D., Sheehan, J. J., Wilkinson, M. G., & Auty, M. A. (2015). Growth and location of bacterial colonies within dairy foods using microscopy techniques: a review. Frontiers in microbiology, vol. 6. pp. 99. 10.3389/fmicb.2015.00099

Kim HJ, Griffiths MW, Fazil AM, Lammerding AM. (2009). Probabilistic risk model for staphylococcal intoxication from pork-based food dishes prepared in food service establishments in Korea. J Food Prot. Vol. 72. pp. 1897–1908.

Lessard, M. H., Bélanger, G., St-Gelais, D., & Labrie, S. (2012). The composition of Camembert cheese-ripening cultures modulates both mycelial growth and appearance. Applied and environmental microbiology, vol. 78(6), pp. 1813-1819.  10.1128/AEM.06645-11

Lessard, M. H., Bélanger, G., St-Gelais, D., & Labrie, S. (2012). The composition of Camembert cheese-ripening cultures modulates both mycelial growth and appearance. Applied and environmental microbiology, vol. 78(6), pp. 1813-1819.

Ma?ej, O., Jovanovi?, S., & Denin, J. (2001). Characteristics of camembert-type cheese ripening produced from milk in which complex between casein and whey protein is formed. Journal of Agricultural Sciences, vol. 46(1), pp. 57-69.

Otto, M. (2014). Staphylococcus aureus toxins. Current opinion in microbiology, vol. 17, pp. 32-37.

Saadat, Y. R., Fooladi, A. A. I., Shapouri, R., Hosseini, M. M., & Khiabani, Z. D. (2014). Prevalence of enterotoxigenic Staphylococcus aureus in organic milk and cheese in Tabriz, Iran. Iranian journal of microbiology, vol. 6(5), pp. 345.

Schelin, J., Wallin-Carlquist, N., Thorup Cohn, M., Lindqvist, R., & Barker, G. C. (2011). The formation of Staphylococcus aureus enterotoxin in food environments and advances in risk assessment. Virulence, pp. 2(6), vol. 580-592. 10.4161/viru.2.6.18122

Wattinger, L., Stephan, R., Layer, F., & Johler, S. (2012). Comparison of Staphylococcus aureus isolates associated with food intoxication with isolates from human nasal carriers and human infections. European journal of clinical microbiology & infectious diseases, vol. 31(4), pp. 455-464.