Food Spoilage and Disease Flashcards
What are the main factors that affect the ability of microorganisms to survive, grow or multiply in food?
Time Available nutrients moisture temperature PH gas atmosphere
List the main foods that are normally considered to be potentially hazardous
- raw and uncooked meats
- diary products
- seafood
- cooked rice and pasta
- food with eggs, beans or other proteins
List four most common pathogens that cause foodborne illness in Australia? āN-E-C-Sā
Norovirus
E. Coli
Campylobacter
Salmonella
How can foodborne illness be caused by A. eating foods contaminated by infectious microorganism or B. by eating foods containing microorganisms that produce toxins
A. Infections can be caused by contaminated food with infectious microbes for example salmonella can enter the GI tract from contaminated undercooked poultry
B. Or staphylococcal toxin is produced by staphylococcal aureus bacterium
List the main types of microorganisms that cause foodborne illness and give several examples of each of these
Bacterial Infection Bacterial Intoxification Viruses Protozoa Helminths (parasites/ worms) Algal toxins
What symptoms can be caused by consumption of marine toxin contaminated fish or shellfish?
tingling, burning, numbness, drowsiness and difficulty breathing
hot cold inversion (hot feels cold, cold feels hot)
Explain what prions are and describe the health risks associated with them
Prions are small abnormal, distorted proteins that can be found in the cell membranes of brain cells
When in contact with normal brain cell protein, they cause the latter to change shape, with loss of protein functionality
Thought to be infective agent in bovine spongiform encephalopathy (BSE) - made cow disease
They are resistant to heat
Loss of motor control, confusion, paralysis and wasting and death
Describe symptoms of foodborne illness
Nausea, abdominal cramps, diarrhoea, vomiting, fever and headaches
Can cause long term health effects and even death
Symptoms of foodborne illness that signal medical need
Diarrhoea - bloody or lasting for longer than 3 days
Difficulty breathing or swallowing
Double vision
Fever for 24 hrs/longer
Who are more vulnerable to foodborne illnesses?
Those under 5 or over 70
Pregnant women
those with a compromised immune system
Steps people can take to reduce their risk of food borne illness
Clean and sanitise food preparation areas and equipment
Personal cleanliness - hand washing
Temperature control
Avoid cross contamination
Describe factors that combine to determine whether certain compounds in food pose a hazard to human health
The inherent toxicity of the compound
the concentration of the compound in food
the amount of food consumed and how frequently
An individuals suceptibility
Drug or complementary medicines
Explain what cyanogenic glycosides are and give examples of foods that contain them
They are compounds that when broken release hydrogen cyanide
This is a potent respiratory inhibitor and produces damage to issues - most lethal in mitochondria where it binds to the heme iron of cytochrome oxidase and blocks oxidative phosphorylation - impairing vital organs
What are glycoalkaloids and what foods contain them?
They are the chemical compounds derived from alkaloids to which sugar groups are appended
They are contained in potatoes in amounts of 10-100mg/kg
Describe the adverse health effects associated with excessive consumption of glycoalkaloids
Gastrointestinal upset with diarrhoea, vomiting and severe abdominal pain
In severe causes neurological symptoms can occur including drowsiness, apathy, confusing, weakness, vision disturbances and sometimes unconsciousness and death
