Flashcards in Exam 2 -- Fiber Deck (39)
Define Total Fiber
Nondigestible plant polysaccharides that contain beta 1-4 glycosidic linkages which cannot be digested by enzymes in the human alimentary tract
What is the difference between dietary fiber and functional fiber?
Dietary fiber is the fiber found in foods. Functional fiber is the fiber added to foods or taken as supplements that have shown to have health benefits.
Give an example of dietary fiber
Fruits and vegetables
Which fiber molecule is found mostly in legumes, wheat bran, nuts, and root vegetables?
Which fiber molecule is found in apples, strawberries, raspberries, citrus fruits, and oat products?
Which fiber molecule is large, has bonding that is non-digestible by enzymes, and is found in whole-grain food products?
Name the three fiber molecules that are water in soluble
Cellulose, some hemicelluloses, Lignan
Name the 7 fiber molecules that are water-soluble
Pectin, gums, beta glucans, fructans, mucilages, algal polysaccharides, some hemicelluloses
Where is cellulose found in nature?
Plant cell walls
What purpose does gum serve in food?
For filling purposes
Which type of fiber has a greater water holding capacity? Soluble or insoluble?
Why does fiber make you feel more satiated? What can it help you with?
You feel more satiated because it absorbs water and gets bigger and bigger. It can help with weight loss when you are feeling more satiated.
Why is too much fiber bad for you?
Too much fiber leads to less effective digestion because gastric juices and enzymes become trapped in fiber molecules
What effect does fiber have on the stomach emptying rate?
It slows down the stomach emptying rate and makes you feel more satiated
Does fiber increase or decrease food transit time?
Fiber both increases and decreases transit time
In the small intestine, do we want food to go slower or faster?
Slower so that it can absorb more nutrients
What is the term for a food transit that is moving too fast?
What is the term for when food transit is moving too slow?
Explain why it is good to have fiber with cholesterol intake
Fiber can bind to bile acids, so the body must utilize stored cholesterol to create its own bile acids. Therefore, you will not be absorbing as much cholesterol
Name the six physical properties of fiber
Water holding capacity, viscosity, ion exchange capacity, finding of organic compounds, bacterial fermentation, antioxidant
Water holding capacity is greatest in fibers with little amounts of _______ bonding (ie soluble)
Is soluble fiber or insoluble fiber more viscous? (thicker)
Soluble is more viscous (thick)
Fiber has an ion exchange capacity, binding easily to cations. Explain how this will affect absorption.
When too much fiber is ingested, the fiber sticks to cations such as zinc and calcium which in turn have trouble being absorbed
Is binding of fiber to organic compounds greater in soluble or insoluble fiber? Give examples of organic compounds
Soluble; cholesterol & bile acids
Anaerobic bacteria can digest many fiber molecules except for _____
_____ is the sensation in your stomach walls that tell you when you're full
Define transit time
Time that food is in the small and large intestine
Name the 10 physiological roles of fiber
Delayed gastric empty, satiety, transit time altered, altered nutrient absorption, increased fecal bulk, increased bile acid and cholesterol secretion, increased microflora in the colon, reduction of free radicals, altered intestinal morphology, reduced 2 degree bile formation
In regards to intestinal transit time, what is the difference between ingesting soluble and insoluble fibers?
Insoluble=normalized transit time
Soluble=delayed tt (compared to insoluble)