Microorganisms are important in the production of many food related products. Fi
ID: 88760 • Letter: M
Question
Microorganisms are important in the production of many food related products. Fill in the table below with 4 examples of microorganisms important in foods that you enjoy. There is an outbreak of Staphylococcus aureus food poisoning in the Salem, OR area. A common factor in all the hospital cases is that people affected with symptoms said they had eaten at the Popeyes Louisiana kitchen and that all of them had ordered the coleslaw with their delicious chicken meals. What techniques and procedures learned in class could you use to determine if there is S. aureus contaminating the coleslaw? Three different workers were responsible for preparing the coleslaw during business hours. Jill prepared the coleslaw in the morning. Steve prepared the coleslaw in the afternoon and Jack made the coleslaw in the evening. Using the information below, A) Calculate the Staph CFU/gram of coleslaw for each sample. B) determine who might have contaminated the coleslaw. gram of coleslaw was used from each sample. Origin of contamination:Explanation / Answer
The following microorganisms are important in our day to day life.
Microorganism
Type of microorganism
Food or beverage
Lactococcus lactis
Bacteria
Cheese
Acetobacter aceti
Bacteria
Chocolate
Aspergillus oryzae
Fungus
Soy sauce
Bifidobacterium bifidum
Bacteria
Dairy products
Lactobacillus acidophilus
Bacteria
Yogurt
Saccharomuces cerevisiae
Fungus
Bread
Mention correct phenotypic characteristics
Microorganism
Presence of conidia
Presence of sporangia
Type of hyphae
Aspergillus sp.
Yes
No
septate
Penicillum sp.
Yes
No
Septate
Rhizopus sp.
No
Yes
Non-septate
Aspergillus and Penicillum belong to Actinomycota while Rhizopus belongs to Zygomycete.
Staphylococcus aureus can be identified using various biochemical tests. It is a gram positive bacteria which gives positive results for catalse, citrate, gelatin hydrolysis, hemolysis, methyl red and coagulase test. Usually,laboratory methods for scrrening include growth on Mannitol salt agar and/or Dnase tests and then further confirmation is done using tube coagulase test.
Coagulase test is the ability to clot plasma.S. ureus is capable of producing DNase enzyme. Also it has the ability to produce thermostable nuclease (TNase).
From the given data the coleslaw prepared by Jill had the lowest count of S. aureus (10) while the highest was in the preparation by Steve (2.3*107). Thereore the Steve was responsible for contamination of coleslaw.
Microorganism
Type of microorganism
Food or beverage
Lactococcus lactis
Bacteria
Cheese
Acetobacter aceti
Bacteria
Chocolate
Aspergillus oryzae
Fungus
Soy sauce
Bifidobacterium bifidum
Bacteria
Dairy products
Lactobacillus acidophilus
Bacteria
Yogurt
Saccharomuces cerevisiae
Fungus
Bread