Topic 5

Question 1

food poisoning

Answer 1

illness from consuming a food that contains a harmful substance, harmful microbes or their toxins

Question 2

what are common symptoms of food poisoning?

Answer 2

o Stomach aches
o Vomiting (common)
o Diarrhea (common)
o Fever

Question 3

how is the risk of food poisoning assessed?

Answer 3

o How likely it is that you will be harmed?
o What kind of harm?
o How severe is the harm?

Question 4

food spoilage

Answer 4

any kinds of changes occurring in the food making the food unfit for consumption - may or may not be harmful

Question 5

how can foods be contaminated?

Answer 5

o Chemical hazards
o Physical hazards
o Biological hazards

Question 6

what are the chemical hazards found at home?

Answer 6

o To clean kitchen surfaces & equipment

o Pesticides

Question 7

food additives

Answer 7

intentionally added to the food, must include a defined purpose for addition to be acceptable

Question 8

how are the limits for various additives created?

Answer 8

set based on: risk assessment & dose response curve

Question 9

what is the purpose of food additives?

Answer 9

increasing shelf life or enhancing flavour

Question 10

GRAS

Answer 10

generally regarded as safe, list used in US from what food additives are acceptable & safe additives

Question 11

what are types of food additives?

Answer 11

Antimicrobial agents

Sugar & salt

Nitrites

BHA & BHT

sulfites

Question 12

how are nitrites used as a food additive?

Answer 12

can be converted into nitrosamine (carcinogenic)

Nitride levels are considered safe, nitrides used don’t generate high enough levels to create enough nitrosamine to cause cancer

Prevent microbe growth, prevent oxidation of myoglobin & increase water holding capacity of meat

Question 13

how are BHA & BHT used as a food additive?

Answer 13

antioxidants, added to oils to prevent oxidation of FAs

Question 14

how are sulfites used as a food additive?

Answer 14

prevent colour change

Question 15

contaminants

Answer 15

unintentional products that are present in the food, accidentally added to food

Question 16

what are exs of contaminants?

Answer 16

pesticides

plant hormones

animal growth hormones

a/bs

arsenic

Hg in sea foods

Question 17

pesticides

Answer 17

added to crops to protect crops from pests

Have variable degradation times, after crops are sprayed they must wait a certain amount of time before its harvested

Question 18

plant hormones

Answer 18

promote growth or increase size of plant

Get out of sys of plant after a certain amount of time

There is a waiting period before it is safe to consume

Question 19

animal growth hormones

Answer 19

♣ Aren’t used as much in Canada
♣ Used to get a larger animal
♣ Can behave like insulin when consumed in meat, can cause insensitivity to insulin leading to type II diabetes
♣ Growth hormones are only used in the beef industry
♣ There is a buffer zone period from which the hormones are excreted & when the animal can be slaughtered

Question 20

arsenic

Answer 20

added to a chicken’s diet b/c it makes them grow faster

By the time their slaughtered, there shouldn’t be any arsenic left

Question 21

Hg in sea foods

Answer 21

denatures PROs

♣ Crude amounts are contaminated in sea foods
♣ Methyl mercury is very poisonous, can be fatal called minamata disease

Question 22

what are natural toxins found in food?

Answer 22

mycotoxins

solanine

cyanogens

goitrogens

marine toxins

Question 23

mycotoxins

Answer 23

toxins found in fungi
Picking mushrooms in nature
Mold on cheese

Question 24

solanine

Answer 24

toxin in green potatoes

Potatoes will turn green when exposed to light

Question 25

cyanogens

Answer 25

toxins in foods that contain cyanide | Plant foods, ex: sprouts in kidney bean plants

Question 26

goitrogens

Answer 26

substances that cause a problem called goiter (enlargement of a gland) Ex: present in cabbage in small amounts

Question 27

marine toxins

Answer 27

fish come into toxins which are then consumed by humans

Question 28

what are physical hazards in food?

Answer 28

foreign matter can: physically injure someone introduce harmful bacteria

Question 29

exs of forgein matter

Answer 29

``` dead insects hair (not high risk) jewelry glass pieces of metal ```

Question 30

what are biological hazards in food?

Answer 30

microbes that make us sick: viruses bacteria parasites - egg present in food & food wasn't cooked properly to irradicate them mould - fungi

Question 31

what are the most common causes of food poisoning?

Answer 31

viruses & bacteria

Question 32

where do the majority of food borne illnesses occur?

Answer 32

at home or at a restaurant (not the manufacturer)

Question 33

what country has the most cases & deaths reported as a result of food borne illnesses?

Answer 33

india

Question 34

what are the factors affecting the growth of microbes?

Answer 34

nutrient availability water activity pH availability of oxygen temp food structure & composition

Question 35

chemotroph

Answer 35

use E from chemicals

Question 36

phytotroph (autotroph)

Answer 36

use E from sunlight to make their own food

Question 37

chryptofraction

Answer 37

microbes that break down PROs

Question 38

what microbes carry out fermentation? & what do they do?

Answer 38

carbs are broken down anaerobes

Question 39

what are ways microbes acquire their nutrients?

Answer 39

o Chemotrophic: use E from chemicals o Phytotrophic (autotrophs): use E from sunlight to make their own food o Chemotrophs are more of the concern, will grow on certain substrates o Chryptofraction – microbes break down PROs o Fermentation – carbs are broken down by anaerobes o Hydrolytic rancidity – FAs are broken down by microbes

Question 40

water activity

Answer 40

how much water is available for the microbes to grow

Question 41

what does it mean when the water activity is 1?

Answer 41

1 = all water is free, microbes have all water available

Question 42

optimal pH

Answer 42

microbes will have the fastest growth rate

Question 43

aerobic microbes

Answer 43

mold & most food spoiling bacteria

Question 44

facultative anaerobic microbes

Answer 44

can grow with or without oxygen but prefer no oxygen

Question 45

where can anaerobic microbes survive?

Answer 45

canned foods

Question 46

mesophilic temp

Answer 46

25-45C

Question 47

psychrophilic

Answer 47

low temp

Question 48

psychotropic

Answer 48

can survive at low temps but optimal is 25-30C

Question 49

optimal growth

Answer 49

temp which growth is the highest

Question 50

max growth temp

Answer 50

max temp at which bacteria can still grow

Question 51

min growth temp

Answer 51

min temp at which bacteria can still grow

Question 52

what does PRO decomposition lead to?

Answer 52

putrifaction (death)

Question 53

what does carb decomposition lead to?

Answer 53

fermentation

Question 54

what does carb decomposition lead to?

Answer 54

hydrolytic rancidity

Question 55

what causes food borne illnesses?

Answer 55

infection or microbial toxins

Question 56

toxin mediated infection

Answer 56

microbes that survive on the digestive tract & produce toxins inside our body causing harm

Question 57

salmonellosis & prevention methods

Answer 57

o Non-spore forming o Leads to jaundice – occurs when hemoglobin is broken down & red blood cells die o Present in high amounts in poultry (but it’s all over) o Prevent cross-contamination by thoroughly cooking, holding at high temp & proper cooling o Store properly to prevent

Question 58

bacillus cerus gastroenteritis & prevention methods

Answer 58

time/temp control Found in starch foods Microbe will grow when food sits at room temp The longer it sits, the more likely it will form Fried rice syndrome

Question 59

botulism, C. botulinum & prevention methods

Answer 59

produces toxins in anaerobic conditions Low acidic canned foods Ex: garlic, beans etc. Don’t germinate in an acidic envr Illness: botulism Prevention: keeping the correct temp for storage Produces spores

Question 60

listerosis - microbe? & prevention methods

Answer 60

Listeria monocytogenes Control temp – cold storage Continues to grow at low temps Epiry date is important

Question 61

Hemorrhagic colitis - microbe & prevention methods

Answer 61

E. coli Present in feces Certain strains aren’t harmful, ex: the strain that exists in the large intestine producing vit K Harmful strains destroy red blood cells at such a fast pace that when kidneys are trying to filter the blood the nephrons are blocked & can be toxic When cells die, they block the nephrons, nitrogenous waste cannot escape & circulates through the body Prevented by proper cooking temp Assoc with raw ground meat

Question 62

Shigellosis - where? & when does it occur?

Answer 62

Occurs due to improper personal hygiene, flies etc. Found in ready to eat foods, contaminated after cooking

Question 63

what are the 5 most common causes of foodborne illness due to improper food handling?

Answer 63

Improper holding time & temp Poor personal hygiene Inadequate cooking Contaminated equipment Food from an unsafe source

Question 64

high hold temp

Answer 64

keep hot food hot, above 60 C

Question 65

proper cooling

Answer 65

keep cold food cold Getting from 60C to 21C within the first 2 hours & from 21C to 4C within next 4 hours Reduce size stainless steel containers are better to use uncover the container store on higher shelf Icepack and ice baths are a good way to cool

Question 66

thawing

Answer 66

in the fridge

Question 67

what are other ways to practice good food handling techniques?

Answer 67

• Internal cooking temperatures • If food is out for 2 hours, it is unsafe • Store in refrigerator • 4-60C is the frame in which microbes will grow • Transfer food into diff containers than the one they were cooked in • Store hot food on the top shelf so it doesn’t affect other food • Store in containers that are good heat conductors (steel vs. glass) • Wash hands properly for 20 secs • Cover any cuts on hands • Don’t cut yourself when handling food • Don’t use cellphones when handling food • Wash dishes thoroughly, if dishes touch raw meat then clean them before use • Internal temp is the best way to determine if the meat is fully cooked o Calibrate thermometer before use