CHAPTER 8: FATS AND OIL Flashcards
all edible lipids that are solid at room temp
fat
all edible lipids that are liquid at room temperature
oil
t/f: only fats are triglyceride esters of fatty acids
false, fats and oil both are
most vegetable oils are polyunsaturated except _____
coconut oil which is largely consists of medium chain saturated fats
temp at which fats becomes an oil
melting point
remains crystalline or solid at room temperature, high boiling point
high melting point
requires less heat to melt, liquid at room temperature
low melting point
t/f: highly saturated = low melting point
false, highly saturated = high melting point
t/f: small crystals, high melting point
true
t/f: large crystals, low melting point
true
t/f: unsaturated = high melting point
false, low melting point
ability of fat to retain shape, a property of solid fats
plasticity
t/f: the more saturated it is, the more it is solid
true
t/f: fat with larger crystals are more plastic
false, fats with smaller crystals are more plastic
temp at which fat becomes overheated
smoke point
t/f: high smoke point is desirable for frying
true
spoilage of fat
rancidity
due to hydrolysis of triglycerides which liberates free fatty acids and glycerol (thru heat or lipase)
hydrolysis
due to oxidation of unsaturated fatty acids in fat by peroxides which in turn results in the formation of other molecules like ketones, aldehydes
oxidative rancidity
what are desirable fat for deep frying?
fats with high smoking point
ability to produce tenderness in flour mixtures by water proofing flour particles thus preventing coalescing of gluten particles
shortening
dispersions of the suspension type, consisting of two liquids which are immersible with each other
emulsions
the weight of _____ indicates the amount of unsaturation in fat
iodine number
t/f: higher iodine number, more double bonds that could result in oxidative rancidity
true
