Chapter 3 Flashcards
(31 cards)
Why is there a higher incidence of food borne incidence?
- Meals eaten away from home
- Diverse food range
- Increase in high risk populations (elderly)
- Better diagnosis
Food Spoilage
Reduction in food’s quality through physical, chemical or sensory properties deteriorating
How can food spoilage occur
Nature enzymes (mould, yeast) attacking food. Food becomes less pleasant to eat, not necessarily poisonous
Examples of food spoilage
- Biscuits absorbing air moisture - going soft
- Bread/cake going stale - loss of moisture
- Mould growth on - jam, bread, citrus fruits, cheese
- Milk going sour
- Bruised/overripe fruits
Food Poisoning
Illness caused by consuming foods contaminated by bacteria, viruses or toxins. Food may appear harmless and physical properties may be normal
Bacteria
Single cell organism - consumed in live food or through toxins produced when ingested. (Most common form of F.P)
Salmonella
Infection when containing live bacteria in food product, on hands or in water and is consumed
Can be fatal for elderly
70% of all F.P cases
Examples of salmonella
Raw meat, poulty, mayonnaise, frozen berries
Symptoms of salmonella
N, D, H - 12-72 hours after, lasts 4-7 days
Lysteria monocytogens
Eating food with listeria monocytogens - found in the environment (soil, water), can grow in extreme conditions (refrigeration & pasteurization), causes illness called lysteria
Foods affected by lysteria monocytogens
High risks food prepared badly, milk, soft cheese (brie, camembert, feta)
Who is affect by lysteria monocytogens
People with weak immune systems e.g. the elderly
Toxins
Bacilius cereus
Bacilius cereus
Spore forming, found in soil, air, dust - tough protective coat (remain dormant), can resist high temps
What foods are affected by bacilius cereus
Boiled rice cooling @ room temp, starchy vegies (potato)
Symptoms of bacilius cereus
N, D, V - mild (24 hours)
Viruses
Minute organisms, smaller than baceria e.g. Hepatitis A
Hepatitis A
Transferred from ears, nose, hands, faeces from infected person from poor food handling/personal hygiene
Contaminated water, fruit, vegies, shellfish
What does Hepatitis A cause
Infected liver, F, N, dark urine, jaundice, abdominal pain
How does bacteria reproduce
F A T T O M
Food Supply, Acidity (low), Time, Temperature, Ocygen, Moisture
Food Supply & e.g.
Bacteria grows in some high risk foods (high protein/starch) more moisture - more growth e.g. milk, soft cheese, meat, fish, poultry, rice, pasta, potato
Acidity (low) & e.g.
pH over 4.6 - protein based foods e.g. milk, eggs, not vinegar or jam
Time & how long
Bacteria can split itself - divide every 20 minutes - binary fission - 17 million bacteria in 8 hours
Oxygen & methods used
Needed for bacteria survival and reproduction - stop by canning, vacuuming, dehydration – extends shelf life
