Exam 2 Review

Exam 2 Review - Exam 2 Review: DIETARY FIBER:...

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
Exam 2 Review: DIETARY FIBER: -Nondigestible Carbs and lignin that are intact and intrinsic in plants FUNCTIONAL FIBER: -Nondigestible carbs that are isolated, extracted, or manufactured and usually known to have physiological benefits -Cellulose -Pectin -Lignin -Beta-Glucans -Fructans -Chitin and Chitosan -Polydextrose and Polyols -Psyllium -Resistant Dextrins -Resistant Starches CELLULOSE: -Dietary and functional fiber -Long, Linear Polymer of Beta- 1-4 Linked Glucose Units -Main component of plant cell walls -Sources: Bran, legumes, nuts, peas, root vegetables, cabbage family, outer covering of seeds, apples PECTINS: -Dietary and functional fiber -Complex group of polysaccharides called Galacturonoglycans -Backbone = Galacturonic Acid -Water-Soluble, Gel-Forming -Sources: Apples, Strawberries, Citrus FRUCTANS- ISULIN, OLIGOFRUCTOSE & FRUCTOOLIGOSACCHARIDES: -Dietary Fiber -Fructose Units in chains of varying lengths PREBIOTICS: -Encourage bacterial growth SOURCES: -Asparagus -Onions -Garlic -Artichokes -Bananas
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
-Tomatoes RESISTANT STARCH: -Starch that cannot be digested by humans includes starch from plant cell walls, ungelatinized starch granules (unripe bananas), retrograde starch from cooking and cooling, or extruded foods and chemically modified starch -Resistant starch from cell walls and ungelatinized starch are considered dietary fiber; while retrograde starch and modified starch are functional fibers (come from highly processed foods) SOLUBILITY IN WATER: SOLUBLE: -Delay gastric emptying -Increase transit time in intestine (takes longer to go thru intestine) -Decrease nutrient absorption INSOLUBLE: -Decrease transit time in intestine -Increase fecal bulk SOLUBLE: -Dissolve in hot water -Some hemicelluloses -Pectin -Gums -Beta Glucans INSOLUBLE: -Don’t dissolve in hot water -Lignin -Cellulose -Some hemicelluloses DEGRADABILITY/FERMENTABILITY: FERMENTABLE FIBERS: -Fermentable fibers as prebiotics -Short-chain fatty acid generation -Increased water & sodium absorption in the colon -Mucosal cell proliferation -Provision of energy -Acidification of luminal environment HYPOGLYCEMIC & HYPOLIPIDEMIC EFFECTS OF SOLUBE FIBERS ARE USEFUL FOR:
Background image of page 2
-Diabetics and those with high serum cholesterol -Slow down glucose peaks (insulin release) INSOLUBLE, NONFERMENTABLE FIBERS USEFUL FOR GI DISEASES: -Diverticular disease -Gallstones -Constipation ROLES OF FIBER IN COLON CANCER: -Absorb bile acids promote fecal excretion -Increase fecal bulk -Provide fermentable substrates for bacteria in colon which decreases tumor cell growth -Shortened fecal transit time -Decreases interluminal H, so decreases synthesis of secondary bile acids which are carcinogenic -Fermentation may release fiber-bound calcium (calcium may increase growth of cancer cells) -Butyric acid appears to reduce growth of cancer cells -Insoluble fibers bind carcinogens LIPIDS: SIMPLE LIPIDS: -Fatty acids -Triacylglycerols -Diacylglycerols -Monoacylglycerols COMPOUND LIPIDS: -Phospholipids
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 11

Exam 2 Review - Exam 2 Review: DIETARY FIBER:...

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online