LAB 3 Flashcards
(37 cards)
____ protect your body’s cells from damage
antioxidants
a diet rich in antioxidants can help lower risk of ____
heart diseases and diabetes
an antioxidant can be: (3)
- a vitamin such as vit A, C or E
- phytochemical
- mineral such as selenium
phytochemical fund in plant foods include: (5)
IMPORTANT
- flavonoid anthocyanin (Berries and red cabbage)
- carotenoids such as lutein (greens and orange-colour plant foods) an lycopene (tomatoes)
- indole glucosinolate (cruciferous vegetables)
- allicin
- catechins (green tea)
How are nutrients lost in food?
due to light, heat, air exposure, leaching into cooking water
what is the preferable method of preparing vegetables?
peel and cut into large pieces fruits and veggies prior to consumption and cooking
how can you maximize nutrient retention?
- peeling should be avoided as nutrients are concentrated just below the skin or left until after cooking
- using minimal amounts of water, or where water or liquid in consumed
___ are also concentrated sources if antioxidants
herbs
what are glucosinolates?
- sulfur-containing compounds found in cruciferous vegetables
- very water soluble and better absorbed if food source is well chewed
how can you optimize glucosinolate availability?
give examples of glucosinolate-containing foods
- quickly cooking in small quantities of water
- brussel sprouts, collards, kale, watercress, turnips, cabbage, broccoli, rapini, cauliflower, mustard greens
___ provide the red blue colour in foods such as berries eggplant and red cabbage. they are _____ pigments that vary in colour according to __.
anthocyanins
water soluble pigments
pH
in ___ environment, anthocyanins are red and in ___ environments they are blue, greenish-blue or black
acidic
basic
what molecule is present in garlic and onions, shallots and chives? what are they called? what is the best source?
allicin is present in the alliums
best source: freshly crushed garlic
green tea, onions and grapes (wine) contain large amounts of ___. green tea should be steeped for 8-10min to extract maximal amount of this antioxidant
flavanols
which chlorophyll molecule is blue-green?
which is yellow-green?
chlorophyll a
chlorophyll b
how do you enhance chlorophyll’s vibrant green color?
blanching quickly and rinsing in cold water immediately after cooking
what happens during blanching?
air escapes from vegetable and allow the color to appear brighter
when green veggies and cooked, plant cells rupture and release ______. ____ containing chlorophyll become permeable to these. ____ from what is released, displace the central ____ atom in chlorophyll to form either _______ (grey-green) or ______ (dull yellow-green)
organic acids plastids hydrogen ions magnesium pheophytin a pheophytin b
how can you minimize the formation of pheophytin?
cooking green veggies in an uncovered pan as quickly as possible to allow volatile acids to escape
exposure to ___ (baking soda) can split the phytyl group to form the _____, a pigment with a bright green colour that easily leaches into cooking water
alkali
sodium salt chlorophyllin
what are the disadvantages of using baking soda? (3)
- destruction of the B vitamin thiamin
- a bitter taste
- mushy texture
exposure of chlorophyll to __ or ___ also changes its color to bright green
zinc or copper
how do you keep greens green and healthy? (6) explain why for each
- use a large quantity of water as if you were cooking water -> to dilute acids from the veggies
- add salt to water -> for flavour and slightly faster cooking
- have salted water at a rolling boil before you add veggies -> prevent vitamin C loss
- cook veggies uncovered -> allow volatile acids to evaporate from boiling water
- plunging in ice water immediately after cooking -> stop cooking process
- time cooking carefully -> chlorophyll loses its bright green colour after 7 minutes of cooking (cooking for too long is the main reason for colour change)
____ are yellow, orange and red pigments. they are ___ soluble substances
carotenoids
fat soluble