Exam Review III Flashcards
1
Q
Kitchen safety and hygiene
A
- 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
2
Q
Storage: fruit and vege
A
minimise heat, light and oxygen exposure
Aim to buy the freshest produce at point of sale
3
Q
Storage: eggs
A
refrigerate
can stay fresh in fridge for about a month
4
Q
storage: canned foods
A
- 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
5
Q
Food prep: peeling fruit nad veg
A
- 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
6
Q
Food prep: soaking
A
- reduces levels of phytates in grains, legumes, nuts and seeds
- phytates inhibit mineral absorbtion
7
Q
Food prep: germination
A
- 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
8
Q
food prep: yeast leavening and phytates
A
- reduces phytate content of wholemeal bread
- may increase mineral absorption
*
- may increase mineral absorption
9
Q
Food prep: lemon juice
A
- 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
10
Q
cooked foods allow for
A
- 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
11
Q
cooking: nutrient losses
A
- 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
*
12
Q
Cooking methods: blanching
A
- food plunged in boiling water, removes, plunged into iced water or placed under cold running water
- inactivates enzymes which may degrade food
13
Q
Cooking methods: steaming
A
- 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
*
14
Q
Cooking methods: microwave cooking
A
- 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
- heat food quicker than conventional ovens though produce uneven heating within food
15
Q
Cooking methods: barbecued meat
A
- 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
16
Q
Tips to Minimise Nutrient Loss from cooking
A
- 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
17
Q
Cooking Pots, Pans and Utensils
A
- 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
18
Q
define food additives
A
- 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
19
Q
Food additives: regulation
A
- 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
20
Q
Food additives: labelling
A
- 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
21
Q
Food additives: safety
A
- 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
22
Q
Food additive examples
A
- 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
23
Q
health effects of food additives
A
-
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
24
Q
Food additives: ADHD
A
- 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
25
nitrates, nitrites and N-nitrosamines
* 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
26
groups most at risk of the adverse effects of food additives
* children with ADHD
* people with intolerances or sensitivities
* immune suppressed persons
* older adults
* asthmatics
* people with mental illness
27
define food spoilage and what can cause it
* 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
28
potential consequences of eating spoiled food
* 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
* *
29
Food spoilage: microbiological
* 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
30
food spoilage: hazardous foods
* food is considered potentially hazardous if it has to be kept at a certain temp to minimise pathogens
* eg
31
foodborne illness
* 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
32
bacterial infections
* due to microorganisms that invade mucosa of the human gut
* salmonella
* e coli
* campylobacter species
* etc
*
33
viral infections
* rotavirus or norovirus
* both very infectious
34
protozoan and helminthic infections oathogen examples
* protozoan: eg toxoplasma gondii
* helminthic eg cestodes (tape worm)
35
bacterial intoxications
* 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
36
Fungi and moulds may produce toxins known as...
mycotoxins
*
37
Marine toxins
foodborne illness caused by eating contaminated fish and shellfish
* can occur when marine animals consume large amounts of algae which can produce toxins
38
Prions
* 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
39
foodborne illness symptoms
ranges from mild to severe, develops few hours to days after
symptoms: nausea, abdominal cramps, vomiting
40
most common cause of diarrhoea in the industrial world
campylobacter jejuni
41
population groups prone to food borne illness
children under 5
pregnant women
older groups
those with compromised immunity
42
prevention of foodborne illness
* food hygiene and handling
* herbs and spices with antimicrobial action
* pro/prebiotics
*
43
cyanogenic glycosides
* 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
44
potatoes: glycoalkaloids
* 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
45
goitrogens
* substance which may cause enlargement of thyroid gland when paired with low iodine consumption and/or low dietary selenium
* cruciferous vegetables contain goitrogenic compounts
46
lectins
* 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
47
minimising risk of natural toxins
* eat wide variety of foods
* store and prepare foods properly in order to inactivate/eliminate potential natural toxins
*
