Chapter 18: Food Safety: Sources of Contamination Flashcards
What is Contamination?
Is the state of being impure or unfit for use due to the introduction of unwholesome or undesirable elements
When does contamination occur?
It occur when something not normally found in the food is added
What are the 3 types of food contamination?
- Physical
- Chemical
- Microbial
What are Physical Contaminant?
These are nonliving substances that become part of a food mixture such as
ie) metal fillings, broken glass, rodent droppings and packaging materials
Physical contaminations can..?
- Create health hazards
2. Occur at any point in food growth or production
Pesticide Residue can do what?
Pesticide residue left on food can enter the food supply
- The USDA and CFIA, monitors pesticides and conducts tests to determine if residues pose a health hazard
Some Toxic substances that may enter water are?
mercury, cadmium, lead, chloroform, and benzene
What is Food Spoilage?
Is a change in food that makes it unfit or undesirable for consumption
Microbes and enzymes often work together to do what?
Microbes and enzymes often work together to cause spoilage
What are Pathogens?
In food cause most of foodborne illness, which involves..
- nausea, stomach cramps, vomiting, diarrhea
What is an outbreak of foodborne illness?
2 or more people becoming ill from eating the same food
How do Pathogens cause illness?
Pathogens cause illness by intoxication or by infection
What is Foodborne Intoxication?
A foodborne illness caused by a toxin released by microbes
What are toxins?
Toxins are metabolic by-products released by microbes that are harmful to humans
Killing microbes does what?
Killing microbe is not enough to make food safe since the toxin must also be denatured
Microbes release what?
Several common microbes release toxins
What is Staphylococcus aureus?
Staphylococcus aureus is commonly found on humans and animals
What is the function of Staphylococcus aureus (S. aureus)?
- Is gram positive, facultative, and halophilic
- grows slowly when other bacteria are present
- Is found in red meats, poultry, potato, macaroni, tuna salads, custards and cream-filled pastries
- Has a heat-resistant toxin
What are some foodborne illness caused by S. aureus?
- Can include nausea, diarrhea, vomiting and abdominal cramps
- Is best prevented by proper hygiene, and work habits of food handlers
- Can be prevent by cleaning and sanitizing food equipment
What is Clostridium botulinum (C. botulinum)?
it is an extremely dangerous bacteria
What is the function of C. botulinum?
- Is found in all soil types and in sediments of marshes and lakes
- Uses honey and improperly processed home-canned goods as a food source
- Produces spores that withstand temperatures above the boiling for hours
What are some foodborne illnesses caused by C. botulinum?
- Is called botulism, a progressive paralysis that can cause death by suffocation
- Also causes blurred vision and red, sore mouth, tongue and throat
Infants up to 12 months should not be fed what?
Infants up to 12 months should not be fed honey
What is a Foodborne Infection?
A foodborne illness that occurs when microbes release digestive enzymes that damage body tissue and cause illness is as a foodborne infection
- can be caused by bacteria, parasites, and viruses
What is Escherichia coli (E. coli)?
E. coli are gram-negative, rod-shaped bacteria that live in the intestines of mammals
What is the function of E.coli?
- Infected food handlers and contaminated water transport E.coli to food supply
- There are 7 strains (serotypes) that cause foodborne illness
- The main serotype os E.coli O157:H7
What are some foodborne illnesses caused by E.coli?
- Include diarrhea, nausea, fever, cramps, weakness, aches and vomiting, kidney disease and even death in small children and adults
- Is often due to food contaminated by exposure to raw fecal matter
- Is prevented by chlorinating water supplies, washing hands after using the bathroom, and cooking meat thoroughly
What is Listeria monocytogenes?
is a rod-shaped, aerobic, gram-positive bacterium
Where is Listeria monocytogenes found?
- Found in soil, water and many animals
2. Able to multiply at refrigeration temperatures in 10% salt solutions and at a pH of 9
What are some foodborne illnesses caused by Listeria monocytogenes?
- Include symptoms of fever, headache, nausea, diarrhea and vomiting
- Affects high-risk populations-pregnant women, newborns, and people with weakened immune systems
- can cause miscarriage, stillbirth, and death
What are some food sources of Listeria monocytogenes?
Food sources include soft cheese, uncooked meats, vegetables, unpasteurized milk
What is Salmonella?
Salmonella are rod-shaped, gram-negative, anaerobic bacteria that cause salmonellosis
What is Salmonellosis?
- Symptoms include diarrhea, cramps, fever, nausea, vomiting, chills and headache
- The microorganism is found in eggs, poultry, meat and dairy products
- Prevention includes keeping work surfaces and hands clean and thoroughly cooking food
What are parasites?
Parasitic infections are caused by parasites, organisms that live in and feed on a host
What are some common sources for parasites?
- Contaminated water
- Raw fish and unwashed fruits and vegetables
- Swine, cattle and wild animals
What is Trichinella spiralis?
is a roundworm that occurs in hogs and wild game
- Worms attach to intestinal walls and produce new larvae that travel in the bloodstream to muscle tissue
What is Trichinosis?
An infection cause by Trichinella spiralis; it is destroyed when meat is adequately cooked, cured, smoked or fermented
What is a Virus?
A virus is a microscopic disease-causing agent made of genetic material surrounded by a protein coating called a capsid
What are some characteristics of Viruses?
- Viruses do not multiply in food, but can be transmitted in food
- Cause the most foodborne illness
- A virus must attach to a host cell to multiply
- Viruses can survive on glass, stainless steel, tile, low-moisture food and in ground meat
How are Viral infections transmitted?
Viral infections are transmitted by the fecal-oral route in 2 ways
- failing to wash hands after using bathroom
- using sewage-contaminated water or fertilizer on food crops
What are 3 viruses associated with foodborne illness?
- Rotavirus
- Noroviruses
- Hepatitis A virus
Pathogen transmission by animals occurs when?
Animal feces comes in contact with food (meat or vegetables) or microorganisms are transferred during slaughter or meat packaging
Pathogen transmission due to time and temperature abuse is?
- Is the biggest cause of foodborne illness
2. Involves holding perishable food beyond 2-4 hours at temperatures not cold or hot enough
What is the Temperature Danger zone?
(5-57C or 41-135F)
Most pathogens multiply rapidly in the temperature danger zone
Pathogen transmission due to poor personal hygiene can do what to food?
Pathogen transmission due to poor personal hygiene can make food unsafe
Food handlers and customers are a major cause of what?
Pathogen transmission
How can Pathogen Transmission be prevented?
Prevention includes wearing proper clothing and washing hands frequently and avoiding handling food when ill
What are some sources of food contamination?
hands, breath, hair, wounds, unshielded coughs and sneezes and perspiration
What is Cross-Contamination
Pathogen transmission due to cross contamination
- Occurs when food comes in contact with contaminated surface during harvest, storage, preparation or holding
- Is prevented by thoroughly washing cutting boards, knives and hands after preparing raw foods
Monitoring the safety of the food supply involves what?
- Voluntary effort by the food industry to set and follow standards to prevent contamination
- Government regulation and inspection of food processing plants and their safety-related record keeping
What is HACCP (Hazard Analysis and Critical Control Point)?
is a food safety system used by food producers
- It examines every point in the process where contamination can occur
- A critical point is any step where hazards can be removed, prevented or minimized
- Hazards are anything that can cause harm
How does the HACCP System work?
- Documentation of monitoring and correction at each critical control point is key
- HACCP reduces a food producer’s risk of liability and prevents outbreaks of foodborne illness
What are the 7 principles of HACCP?
- Conduct a hazard analysis
- Identify critical control points
- Establish critical limits
- Establish monitoring procedures
- Establish verification procedures
- Establish verification procedures
- Establish record-keeping and documentation procedures
