I A Food science & nutrient composition: F&V, meat/poultry/fish Flashcards
(116 cards)
crispness is AKA..?**
state of TURGOR (rigidity)
composition of F&V
mostly water, some carbohydrates and vitamins/minerals
crispness is due to what?***
OSMOTIC PRESSURE of WATER-FILLED VACUOLES
with age, F&V increase in what two compounds?
hemicellulose & lignin (a non-CHO substance not significantly softened by cooking)
what is the limiting AA in soybeans?
methionine
chemical changes in F&V are due to?
enzymes
when F&V ripen, starch is changed to?
sugart
order of ripening: pectic acid, protopectin, pectin
protopectin –> pectin (ripe) –> pectic acid (overripe)
what accelerates the ripening of fruits during storage?***
ethylene gas
out of these: tomatoes, onions, avocados, peaches, oranges, bananas, corn on the cob, pears- which ripen best at room temperature?
avocados, bananas, pears, tomatoes
aging in delayed in apples stored in what kind of environment?*****
controlled atmosphere (reduced oxygen) [ROP]
when should berries and mushrooms be washed?*****
JUST before serving!!
fruits low in ______ darken rapidly when cut due to enzymatic action; therefore, do WHAT to prevent?
vitamin C; dip in citrus juice, add sugar before freezing, heat to boiling
of oranges that yields 1 QUART of orange juice**
one dozen (12)
1 quart = ? cups***
4 cups (you know this, but quart = quartile, 1/4)
1 pint = ? cups***
2 cups
cooking vegetables softens what compound?
cellulose (aka plant fiber)
density of a syrup in packaging of fruit is often expressed as a % by weight of what sugar: fructose, glucose, sucrose?
sucrose - measured with a Brix hydrometer
what pigments are LEAST affected by changes in pH?*****
carotenoids (yellow, orange)
what pigments are MOST affected by changes in pH?**
flavonoids (red, blue, purple)
green (chlorophyll), yellow and orange (carotenoids) pigments are all (soluble/insoluble) in water
insoluble
flavonoids are (soluble/insoluble) in water
soluble - therefore, probably likely why they are affected so much by changes in pH
name the color:
- pheophytin
- chlorophyllin
- lycopenes
- anthocyanins
- anthoxanthins
- pheophytin = olive green
- chlorophyllin = bright green
- lycopenes = red
- anthocyanins = red/blue/purple
- anthoxanthins = white
what pigment/compound acts as an antioxidant?
lycopene (red - watermelon, tomatoes, overtones in apricots)