Microorganisms that affect food and their properties

High risk foods:

●       fresh milk

●       white fish

●       fresh meat

●       cheese

●       cream

●       oily fish

●       poultry

●       fresh pasta

 

Low risk foods:

●       crackers and biscuits 

●       cornflakes

●       oats

●       flour

●       nuts

●       dried pasta

●       rice

●       honey

●       sugar

 

Types of Microorganisms:

Micro-organisms

            Bacteria             Virus           Fungi

Name:

Hepatitis A

Cellular structure:

 

Size: 

 

Pathogenicity:

the symptoms range from mild flu like symptoms to illnesses like serious liver disease

 

Location:

 Found in foods handled by people, raw shellfish and soft fruit

 

Growth/reproduction:

The minimum ph for growth is 2. It can survive freezing and is killed by heating to 85c for 1 min.

The illness onset is 15 to 50 days and can last for months

 

Micro-organisms

            Bacteria             Virus           Fungi

Name:

Norovirus

Cellular structure:

 

Size:

 

Pathogenicity:

The symptoms include nausea, severe/ projectile vomiting and diarrhoea

 

Location:

Found in foods handled by people, raw shellfish and soft fruit

 

Growth/reproduction:

The minimum ph is 2. It can survive freezing and is killed by heating to 90c for 90 seconds.

The illness onset is 12 to 48 hours and lasts for less than 48 hours

Micro-organisms

            Bacteria             Virus           Fungi

Name:

Shigella sonnei

Cellular structure:

Bacterium that is rod shaped with a fimbriae

 

Size:

 

Pathogenicity:

Causes sever diarrhoea with blood and pus and abdominal pain

 

Location:

Found in sewage, manure and raw foods

 

Growth/reproduction:

The minimum ph for growth is 4.5. the minimum temperature for growth is 6 to 7c and is killed by heating to 70c for 2 mins.

The illness onset is 12 to 24 hours and the duration lasts for 1 to 5 days

Micro-organisms

            Bacteria             Virus           Fungi

Name:

Salmonella Enteritidis

Cellular structure:

Rod shaped with frimbrie

 

Size:

 

Pathogenicity:

Causes fever, headache, vomiting, abdominal pain and diarrhoea

 

Location:

It lives naturally in the guts if animals. Infection of it is usually linked to foods of animal origin or to direct contact with animals or contaminated water.  Found in raw meat, poultry and eggs

 

Growth/reproduction:

The minimum ph for growth is 4. The minimum temperature for growth is 6c and is killed by heating to 70c for 2 mins.

The illness onset is 12 to 48 hours ans the duration is 12 to 21 days

 

Micro-organisms

            Bacteria             Virus           Fungi

Name:

Clostridium perfingens

Cellular structure:

Rod shaped that forms spores in low oxygen food

Size:

 

Pathogenicity:

It causes diarrhoea…