Domain I-Topic A: Food Science and Nutrient Composition of Foods Flashcards
(227 cards)
What is the crispness of vegetables (state of turgor) due to?
The osmotic pressure of water-filled vacuoles
What is the limiting amino acid in soybeans?
Methionine
What is the percentage of protein in protein concentrates and protein isolates?
> or equal to 70% and 90%
Soybeans are used in…?
Textured protein products
Chemical changes are due to…?
Enzymes
Protopectin (large,insoluble) is converted to _______ (ripe fruit) then converted to ________(overripe fruit)
Pectin; pectic acid
What accelerates ripening of fruits during storage?
Ethylene gas
Which fruits ripen best at room temperature?
Avocados
Bananas
Pears
Tomatoes
If apples are stored in a controlled atmosphere (reduced oxygen), does aging occur faster or is it delayed?
Delayed
When should mushrooms and berries be washed?
Just before serving
Fruits low in vitamin C from darken rapidly when cut due to enzymatic action. How can this be prevented?
- ) Dip in citrus juice
- ) Add sugar before freezing
- ) Heat to boil
Green pigment is due to…?
Chlorophyll…more like borophyll
Green pigments turn olive green in acid due to….?
Pheophytin
Green pigments turn ______ green in alkaline solution (like baking soda) due to…?
Bright; chlorophyllin (mushy; hemicellulose is broken down)
Yellow & orange pigments are the…?
Soluble or insoluble in water?
Little or large effect in acid or alkaline solution?
Carotenoids
Insoluble in water
Little effect
What contributes to the red color in tomatoes and watermelon, and overtones in apricots (act as antioxidants)?
Lycopenes
Flavinoids
Anthocyanins (red, blue & purple)
Anthoxanthins or flavones (white)
Flavinoids are soluble or insoluble in water?
Soluble
Anthocyanins turn ____ ____ in acid and _____ in alkaline.
Bright red; bluish
Anthoxanthins or flavones (white) are ________ in acid and _______ in alkaline.
Colorless; yellow
*Onions turn yellow in aluminum pan
Flavor of fruit is due to…?
acids, sugar and aromatic compounds
What causes an astringent feeling in the mouth? (*Found in underripe bananas)
Tannins
The grade of fruits/vegetables is based on what? (7)
Quality, firmness, color, maturity, freedom from defects, uniform size and shape
Canned Fruits & Vegetables
Grade A
desserts & salads (Fancy)