Exam Review III

Question 1

Kitchen safety and hygiene

Answer 1

• wash hands before handling food and after handling meat, poultry or fish
• tie hair back
• knives in wooden block or drawer
• avoid burns and scalds
• wipe up spills
• electrical appliances away from water
• avoid fires
• avoid cross contamination

Question 2

Storage: fruit and vege

Answer 2

minimise heat, light and oxygen exposure

Aim to buy the freshest produce at point of sale

Question 3

Storage: eggs

Answer 3

refrigerate

can stay fresh in fridge for about a month

Question 4

storage: canned foods

Answer 4

• Most have storage life of 2-4 yrs
• Becuase we don’t know how long they were stored at wholesaler/retailer, about one year is recommended
• Once opened, should be places in clean plastic or glass container

Question 5

Food prep: peeling fruit nad veg

Answer 5

• micronutrients, dietary fibre and phytochemicals are concentrated in or close to the skin surface
• washing and peeling result in loss of water soluble vitamins
• Peeling should therefore be minimised

Question 6

Food prep: soaking

Answer 6

• reduces levels of phytates in grains, legumes, nuts and seeds
• phytates inhibit mineral absorbtion

Question 7

Food prep: germination

Answer 7

• germination of grains and legumes improves the vitamin and mineral content
• reduces levels of phytates, tannins and oxalates
• vit C and riboflavin are synthesised during germination

Question 8

food prep: yeast leavening and phytates

Answer 8

• reduces phytate content of wholemeal bread
  
  • may increase mineral absorption
    *

Question 9

Food prep: lemon juice

Answer 9

• contains citric acid
• presence of organic acids may increase availability of calcium from vegetable foods
  
  • citric acid most effective when followed by tartaric, malic or ascorbic acid
• Can be used to prevent browning from foods such as apples and avos
• Can neutralise fish odour

Question 10

cooked foods allow for

Answer 10

• the evolutionary selection of smaller teeth and gut evolution
• Cooking breaks down the skin, softens cellulose, denatures toxins, and reduces complex proteins while simultaneously enhancing sweetness and increasing the caloric intake of early hominines

Question 11

cooking: nutrient losses

Answer 11

• Results vary depending on amount of water, length of cooking time, temp
• The most unstable vitamins are folate, thiamin (B1) and vit C
• More stable include niacin, vit K and D, biotin, B5
  *

Question 12

Cooking methods: blanching

Answer 12

• food plunged in boiling water, removes, plunged into iced water or placed under cold running water
• inactivates enzymes which may degrade food

Question 13

Cooking methods: steaming

Answer 13

• food heated by direct contact with the steam generated by boiling water
• good for vegetables as retains texture, colour, taste, nutrients
• reduces heated oil intake
  *

Question 14

Cooking methods: microwave cooking

Answer 14

• Microwaves cook food by agitating water and other small molecules to produce frictional heat
• Advantages
  • speed, easy clean up, retains water soluble nutrients, food can be taken from freezer and thawed/cooked quickly
• Disadvantages
  
  • heat food quicker than conventional ovens though produce uneven heating within food
    • cold spots in food increase risk of foodbourne illness
  • loss of vit B12

Question 15

Cooking methods: barbecued meat

Answer 15

• food is in direct contact with flame, pyrolysis of fats in the meat and smoke of hot charcoal generate great amounts of polycyclic aromatic hydrocarbons (PAHs), that mostly accumulate in the outer surface of the barbecued meat

Question 16

Tips to Minimise Nutrient Loss from cooking

Answer 16

• store food properly
• keep vegies in crisper
• wash veg not peel
• steam veg not boil
• use fresh ingredients where possible
• cook foods quick and at low temp

Question 17

Cooking Pots, Pans and Utensils

Answer 17

• made from a variety of materials
  
  • can enter the food cooked in them
• aluminium poses the most harm
  
  • linked to alzheimers and other neurlogical conditions
  • small amounts of aluminium can be excreted but high levels are harmful

Question 18

define food additives

Answer 18

• a substance not normally consumed as a food itself
• is intentionally added to food for enhancing look, taste, texture or storage life
• salt, starch, sugar and water not considered to be additives

Question 19

Food additives: regulation

Answer 19

• food additives regulated by Food Standards Australia New Zealand (FSANZ)
• only additives in Australia New Zealand Food Standards Code may be added to certain foods

Question 20

Food additives: labelling

Answer 20

• If an additive makes up less than 5% of the complete food and is not considered to perform a technological function in the final food, it doesn’t have to be labelled

Question 21

Food additives: safety

Answer 21

• FSANZ carries out safety assessments on food additives before they can be used
• checks whether the food additive is safe and if there is reason for using the additive
• safe levels are determined
  
  • The ADI is the amount of a food additive that can be eaten every day for an entire lifetime without adverse effect

Question 22

Food additive examples

Answer 22

• acidity regulators
  
  • substances that lower the pH of foods
  • metatartaric acid
• anti-caking agents
  
  • substances that main free-flowing characteristics of powdered foods
• anti-foaming agents
• antioxidants
  
  • retard oxidation reactions in food
• artificial sweeteners
  
  • provide sweetness without contributing to energy intake
  • saccharin
• bleaching agents
  
  • cause breakdown of flour pigments
• bulking agents
  
  • give bulk or body to food
• colours
  
  • replace or enhance natural colours
  • may be naturally occuring eg curcumin
• emulsifiers
  
  • eg lecithin
• flavours
• flavour enhancers
  
  • MSG
• food acids
• preservatives

Question 23

health effects of food additives

Answer 23

• artificial sweeteners
  
  • ​eg saccharin
• olestra
  
  • ​a non-absorbable substitute for triglycerides
  • adverse health effects include diarrhea and loose stools
  • abdominal cramps
  • reduces absorption of fat-soluble vitamins and carotenoids
• MSG sensitivity
  
  • ​monosodium glutamate is a flavour enhancer
  • occurs naturally in some foods eg tomato, cured meats, soy sauce
  • MSG consumption is associated with chinese restaurant syndrome

Question 24

Food additives: ADHD

Answer 24

• ADHD is caused by both genetic and environmental factors
• some artificial colours, flavours, some preservatives and salicylates might have a role to play in hyperactive behaviour and learning disabilities in some children
• Artificial Food Colours (AFCs) are not a main cause of ADHD, but they may contribute significantly to some cases, and in some cases may additively push a youngster over the diagnostic threshold

Still inconclusive due to differing reports however there is a link between behaviour and additives

Question 25

nitrates, nitrites and N-nitrosamines

Answer 25

• Nitrates occur naturally in plant foods and nitrites are used as food additives
• nitrites are added to cured meats to inhibit microbe growth and give the pink colour
• The main acute effect of toxic levels of nitrite is methaemoglobinaemia

Question 26

groups most at risk of the adverse effects of food additives

Answer 26

• children with ADHD
• people with intolerances or sensitivities
• immune suppressed persons
• older adults
• asthmatics
• people with mental illness

Question 27

define food spoilage and what can cause it

Answer 27

• A food is usually considered spoiled if the texture, colour, odour or flavour is different from that normally associated with that particular food
• causes
  • microbes
  • physcial damage
  • pest infestation
  • environmental contamination

Question 28

potential consequences of eating spoiled food

Answer 28

• Food may be less pleasurable
• Potential illness if due to microbial contamination or environmental contamination
• may be a reduction in certain nutrients and/or phytochemicals
• *

Question 29

Food spoilage: microbiological

Answer 29

• poses the greatest foodbourne health risk
• Food can appear, smell and taste safe to eat but still harbour disease-causing agents
• microbes can originate from soil, air, water, plants, animals, humans, ingredients, cross contamination
• important factors which etermine if a microbe can live and multiply
  • time, nutrients, moisture, temp, pH

Question 30

food spoilage: hazardous foods

Answer 30

• food is considered potentially hazardous if it has to be kept at a certain temp to minimise pathogens
• eg

Question 31

foodborne illness

Answer 31

• food poisoning if caused by consumption of contaminated foods
  
  • 5.4 mill cases of food pois. in aus every yr
• Norovirus, E. coli and Salmonella are most common pathogens
  
  • ​bacterial, viruses, protozoa etc
• foodborne illness is caused by eating foods contaminated with infectious microbes or containing microbes which produce toxins

Question 32

bacterial infections

Answer 32

• due to microorganisms that invade mucosa of the human gut
  
  • salmonella
  • e coli
  • campylobacter species
  • etc
    *

Question 33

viral infections

Answer 33

• rotavirus or norovirus
• both very infectious

Question 34

protozoan and helminthic infections oathogen examples

Answer 34

• protozoan: eg toxoplasma gondii
• helminthic eg cestodes (tape worm)

Question 35

bacterial intoxications

Answer 35

• Bacteria which cause disease through toxin production
• Toxins may be
  
  • preformed - produced in food while bacteria grows in it
  • enteric - toxins produced after bacteria enters GI tract
• e.g. Staph. aureus

Question 36

Fungi and moulds may produce toxins known as…

Answer 36

mycotoxins

*

Question 37

Marine toxins

Answer 37

foodborne illness caused by eating contaminated fish and shellfish

• can occur when marine animals consume large amounts of algae which can produce toxins

Question 38

Prions

Answer 38

• prions are small proteins found in cell membrane of brain cells
• when it touches normal brain cell proteins it changes their shape/function
  
  • eg occurs in mad cow disease
• are heat and acid resistant so not destroyed by cooking or stomach acid
• symptoms include loss of motor control and confusion

Question 39

foodborne illness symptoms

Answer 39

ranges from mild to severe, develops few hours to days after

symptoms: nausea, abdominal cramps, vomiting

Question 40

most common cause of diarrhoea in the industrial world

Answer 40

campylobacter jejuni

Question 41

population groups prone to food borne illness

Answer 41

children under 5

pregnant women

older groups

those with compromised immunity

Question 42

prevention of foodborne illness

Answer 42

• food hygiene and handling
• herbs and spices with antimicrobial action
• pro/prebiotics
  *

Question 43

cyanogenic glycosides

Answer 43

• certain parts of some plants contain cyanogenic glycosides
  
  • plants protection mechanism against herbivores
• when this plant is chopped/chewed hydrogen cyanide is released
  
  • is a respiratory inhibitor
  • can cause death
  • eg raw flaxseeds

Question 44

potatoes: glycoalkaloids

Answer 44

• high GA content makes the potato bitter
• water insoluble and heat stable
• peeling can reduce GA content
• high GA exposure = aggravation of chronic inflammatory disease eg bowel
  
  • neurological symptoms may also be experienced

Question 45

goitrogens

Answer 45

• substance which may cause enlargement of thyroid gland when paired with low iodine consumption and/or low dietary selenium
• cruciferous vegetables contain goitrogenic compounts

Question 46

lectins

Answer 46

• also known as haemagglutinins because they cause red blood cells to clump
• found in many raw legume seems eg lentils and soy beans
  
  • lectin content reduced by soaking overnight and discarding the water
• lectins can be inactivated by proper cooking
• Symptoms of high consumption
  
  • nausea
  • vomiting
  • abdominal pain

Question 47

minimising risk of natural toxins

Answer 47

• eat wide variety of foods
• store and prepare foods properly in order to inactivate/eliminate potential natural toxins
  *