Food Science First Test

Define Contamination

State of being impure or unfit for use due to the introduction of unwholesome or undesirable elements

Contamination occurs when…

something not normally found in food is added

The 3 types of food contamination are… (3)

1) physical

2) chemical

3) microbial

Define Physical Contaminants

Nonliving substances that become part of a food mixture

Examples of Physical Contaminants (5)

1) Metal Filings

2) Broken Glass

3) Rodent Droppings

4) Insects

5) Packaging Materials

Physical contamination can… (2)

1) create health hazards

2) occur at any point in food growth or production

Insects and rodents ___ food, ___ onto food,  ___ their ___ on food, or their____ may be mixed into food during processing. 

damage; transfer microbes; deposit; waste; body parts

The ___ examines food products for insect parts.

FDA

Define Chemical Contaminants

Pesticide residue left on food can enter the food supply

The ____ monitors pesticides and conducts tests to determine if residues pose a health hazard.

USDA

Examples of toxic substances that may get into water supplies are… (6)

1) Mercury

2) Cadmium

3) Lead

4) Chloroform

5) Benzene

6) PBCs

Main sources of toxins in water supplies are… (2)

1) pesticides

2) industrial waste

Some pesticides have been banned because they are not _____.

biodegradable

Rain can carry _____ to Earth and water can carry ____ into the ___.

airborne exhausts; pollutants; water supply

____ may be dumped into bodies of water.

wastes

______ is often found in industrial waste. This has left to the monitoring of _____ in ___. 

mercury; mercury levels; fish

____ contamination has lessened due to regulations and voluntary industry changes, such as ____ from older dishwares.

lead; lead leaching

Define Food Spoilage

Change in food that makes it unfit or undesirable for consumption

_____ and _____ often work together to cause spoilage.

microbes; enzymes

Microorganisms can create changes in food that cause a ___.

foodborne illness

_____ in food cause most cases of foodborne illness, which involves ___, _____, ____, _____.

pathogens; nausea; stomach cramps; vomiting; diarrhea

An outbreak of foodborne illness is…

2 or more people becoming ill from eating the same food

Pathogens cause illness by either ____ or ___.

intoxication; infection

Define Food Intoxication

foodborne illness caused by a toxin released by microbes

Define Toxins

Metabolic by-products released by microbes that are harmful to humans

Several common microbes release ___.

toxins

Killing the microbe is _____ to make food safe since the toxin must also be ____. 

not enough; damaged or altered

Clostridium Perfringens causes…

a frequent and mild form of food intoxication

Describe the microbe for Clostridium Perfringens (3)

1) gram-positive, anaerobic, and heat-resistant

2) widespread in air, soil, water, and sewage

3) often traced to high-protein foods because it raises stomach pH enough to allow acid-resistant Clostridium Perfringens to survive

Describe food illness from Clostridium Perfringens

1) can occur from 2 to 29 hours after eating contaminated food

2) includes diarrhea, bloating, and cramps

3) can be controlled by following sanitation procedures, and cooking and storing foods at the proper temperatures

Where is Staphylococcus Aureus commonly found? (2)

1) On humans

2) On animals

Describe the microbe for Staphylococcus Aureus (4)

1) gram positive, facultative, and halophilic

2) grows slowly when other bacteria are present

3) is found in red meats, poultry, potato, macaroni, and tuna salads, custards and cream-filled pastries

4) has a heat-resistant toxin

Describe food illness from Staphylococcus Aureus (3)

1) is caused by a heat-resistant toxin

2) can include nausea, diarrhea, vomiting, and abdominal cramps

3) is best prevented by monitoring the health, hygiene, and work habits of food handlers, and by cleaning and sanitizing food equipment

Define Clostridium Botulinum

Extremely dangerous anaerobic bacteria 

Describe the microbe for Clostridium Botulinum (3)

1) is found in all soil types and in sediments of marshes and lakes

2) uses honey and improperly processed home-canned goods as a food source

3) produces spores that withstand temperature above the boiling for hours

Describe the food illness from Clostridium Botulinum (2)

1) is called botulism, which is a progressive paralysis that can cause death by suffocation

2) also causes blurred vision and a red, sore mouth, tongue, and throat

Infants up to _____ should not be fed honey.

12 months

Chemicals are added to meat products t…

destroy Clostridium Botulinum spores

Define Escherichia Coli

Gram-negative, rod-shaped bacteria that live in the intestines of mammals

Infected food handlers and contaminated water transport ____ to the food supply.

Escherichia Coli

There are __ strains that cause foodborne illness.

7

Describe food illness from Escherichia Coli (3)

1) include diarrhea, nausea, fever, cramps, weakness, aches, and vomiting, even death in small children and adults

2) is often due to food contaminated by exposure to raw fecal matter

3) is prevented by chlorinating water supplies, washing hands after using the bathroom, and cooking meat thoroughly

Define Food Infection

foodborne illness that occurs when microbes release digestive enzymes that damage body tissue and cause illness

Food infection may be caused by… (3)

1) bacteria

2) parasites

3) viruses

Define Listeria Monocytogenes

rod-shaped, aerobic, gram-positive bacterium

Describe the microbe for Listeria Monocytogenes (3)

1) harder to kill than many foodborne pathogens

2) found in soil, water, and many animals

3) able to multiply at refrigeration temperatures, in 10% salt solutions, and at a pH of 9

Describe the food illness from Listeria Monocytogenes (3)

1) includes symptoms of fever, headache, nausea, diarrhea, and vomiting

2) affects high-risk populations - pregnant women, newborns, and people with weakened immune systems

3) can cause miscarriage, stillbirth, and death

Examples of food sources of Listeria Monocytogenes (4)

1) soft cheeses

2) uncooked meats

3) unwashed vegetables

4) unpasteurized milk

Define Salmonellae

rod-shape, gram-negative, anaerobic bacteria that cause salmonellosis

What are symptoms of Salmonellae? (7)

1) diarrhea

2) cramps

3) fever

4) nausea

5) vomiting

6) chills

7) headache

The microbe for Salmonellae is found in… (4)

1) eggs

2) poultry

3) meat

4) dairy products

Prevention for Salmonellae includes… (2)

1) keeping work surfaces and hands clean

2) thoroughly cooking food

Parasitic infections are caused by ____, organisms that live and feed on a ___. 

parasites; host

Common sources of parasitic infections include… (3)

1) contaminated water

2) raw fish and unwashed fruits and vegetables

3) hogs, cattle, and wild animals

Define Trichinella Spiralis

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

Infection of Trichinella Spiralis called ____.

trichinosis

Trichinosis is destroyed when…

meat is adequately cooked, cured, smoked, or fermented

Define a virus

A microscopic disease-causing agent made of genetic material surrounded by a protein coating called capsid

Viruses do not multiply in food, but can be transmitted in food. True or False?

True

A virus must attach to a host to ____.

multiply

Viruses can survive on… (4)

1) glass

2) stainless steel

3) low-moisture food

4) in ground meat

Viral infections are transmitted by _____ in __ ways.

fecal-oral route; 2

What are the ways that viral infections are transmitted by fecal-oral route? (2)

1) failing to wash hands after using the bathroom

2) using sewage-contaminated water or fertilizer on food crops

______ is practically eliminated, but other viruses can cause foodborne illness, which are___, ____, _____. 

poliovirus; rotavirus; norwalk virus; hepatitis

Describe Rotavirus (3)

1) Flu-like infection common in children

2) Symptoms include vomiting, diarrhea, and low-grade fever for up to 10 days

3) Prevention involves good hygiene practices

Describe Norwalk Virus (4)

1) Causes a mild flu-like illness

2) Occurs among all age groups and only lasts up to 2 days

3) Outbreaks have been traced to green salads, raw oysters, cake frosting, and chicken sandwiches

4) Prevention involves good hygiene

Describe Hepatitis (4)

1) Viral infection that can cause liver damage, liver failure, and even death

2) Hepatitis A is the only strain that can be transmitted through contaminated food

3) Foods at risk are uncooked salad ingredients, raw shellfish, and foods handled after cooked

4) Infection can be prevented by washing hands and wearing disposable gloves

Describe Prions (3)

1) Form clumps in the central nervous system and brain tissue

2) Disease in cows is called bovine spongiform encephalopathy (BSE) or mad cow disease

3) Disease in humans is called Creutzfeldt-Jakob disease (CJD)

List and describe how pathogens enter the food supply (4)

1) Cross-contamination

• occurs when food comes in contact w/contaminated surface during harvest, storage, preparation, or holding

2) Time and temperature

• involves holding perishable food beyond 2 hours at temperatures not cold or hot enough

• most pathogens multiply rapidly in the temperature danger zone (41F-135F)

3) Poor personal hygiene

• Sources of contamination include hands, breath, hair, wounds, unshielded coughs and sneezes, and perspiration

4) Animal contact

• animal feces or microbes comes in contact with food

• parasites enter the digestive tract while eating raw fish that was not handled properly

List the prevention for pathogens entering the food supply (3)

1) Washing hands frequently

2) Washing items used in raw food preparation

3) Avoiding handling food when ill

Monitoring the safety of the food supply involves… (2)

1) voluntary effort by the food industry to set and follow standards to prevent contamination

2) government regulation and inspection of food processing plants and their safety-related record keeping

Define HACCP (Hazard Analysis and Critical Control Point)

Food safety system used by food producers

Describe HACCP (3)

1) Examines every point in the process where contamination can occur

2) Critical Control Point is any step where hazards can be removed, prevented, or minimized

3) Hazards are anything that can cause harm

HACCP ____ a food producer’s risk of ___ and ___ outbreaks of foodborne illness. These accomplishments can also _____. 

reduces; liability; prevents; increase profits

Steps to develop a HACCP System (7)

1) Conduct a hazard analysis

2) Identify critical control points

3) Establish critical limits

4) Establish monitoring procedures

5) Establish corrective actions

6) Establish verification procedures

7) Establish record-keeping and documentation procedures

The FDA and USDA monitor the safety of the food supply by… (2)

1) setting standards such as cooking and cooling temperatures

2) regulating food shipped across state lines

Local and state health departments monitor…

foods produced and sold within states and regulate foodservice operations

A food business must get a ___ and be _____ to ensure safety and sanitation regulations are being followed before _____. 

permit; inspected; opening

At least ____ supervising employee must be a certified food protection manager.

one

Violations of regulations results in… (3)

1) warning

2) fines

3) closure of the establishment

_____ is the study of matter (makeup, structure, or properties of substances)

Chemistry

Smallest unit of an element is the ___.

atom

Describe Subatomic Particles (2)

1) Protons and Neutrons in the nucleus

2) Electrons spin around the nucleus in orbitals

Describe how chemical bonds hold atoms together (5)

1) Electrons form the bond

2) Each orbital contains 2 electrons

3) The space around the nucleus with one or more orbitals is called a shell

4) Atoms have up to 7 shells

5) The # of shells determines an element’s position (its row) on the periodic table)

______ hold atoms together. 

Chemical Bonds

Define shell

The space around the nucleus w/one or more orbitals

Atoms are most stable when…

the outer shell is full of electrons

Atoms that are not stable will…

share or transfer electrons from another atom

Each group (____) in the periodic table has the same number of electrons in the ______. 

column; outermost shell

An ____ occurs when electrons are transferred from one atom to another. 

Ionic Bond

Describe Ionic Bonds Occurrence (3)

1) This creates a negative charge in one atom and a positive charge in the other

2) An atom with a positive or negative electrical charge is called an ion

3) A cation has a positive charge whereas an anion has a negative charge

Define Ion

An atom with a positive or negative electrical charge

Identical charges ___ each other, but opposite charges ___.

repel; attract

Substances w/ionic bonds… (3)

1) Have crystalline structure

2) Dissolve in water

3) Are metals and nonmetals

Describe Covalent Bonds (2)

1) Form when atoms share one or more pairs of electrons

2) Oxygen will share 2 electrons in its outer shell with 2 hydrogen atoms to form water

Describe Elements (4)

1) Only one kind of atom

2) # of protons = type of atom

3) Organized by their structure and chemical properties 4) Identified by symbols in periodic table of elements

Atomic Number is…

# of protons in nucleus

Atomic Mass is…

sum of the masses of protons and neutrons in the nucleus

Mass of a proton or neutron is…

one atomic mass unit (AMU)

Electron mass is insignificant. True or False?

True