Food Safety and Testing Dr Jennifer Newton BSc, MSc, PhD Managing Director

Very, very small...

Bacteria are everywhere!

Binary Fission Reproduction by Bacteria Replication

20 minutes minutes4 1 hour8 1 hour 20 minutes hour 40 minutes 2 hours 1282 hour 20 minutes 2562 hour 40 minutes 3 hours512 3 hours 20 minutes hours 40 minutes hours hours 20 minutes hours 40 minutes hours32,768 Exponential Growth of Bacteria

To put it another way,... In one day one bacteria will produce 10,000,000,000,000,000,000,000 That would take humans 1,520 years

How do we Keep Food Safe? Separation of low – risk from high risk – High Risk those foods people will eat without heating (ready to eat) – Low Risk those foods people usually do not eat without cooking; e.g. raw meat Good personal hygiene Cleaning Pest Control Proper temperature control

Above 80C most bacteria die Room temperature and body temperature most bacteria grow very qickly Below 0C most bacteria also do not multiply Temperature and Bacteria

Controlling Bacteria’s Growth Heating to very hot Freezing Chilling Use of chemicals (acid e.g. vinegar, preservatives, salt)

How do we know for certain if food is safe to eat? Have a laboratory test it. Food with disease causing bacteria in it tastes and smells the same as food without it.