Complete With 100% Correct Answers
Nutrition exam 2
\.Triglycerides
glycerol and three fatty acids
\.Fatty acids
•even number of carbons
▪Saturated or unsaturated
▪Omega-3 (linolenic) and omega-6 (linoleic) fatty acids
•18-carbon polyunsaturated fatty acids
\.Bonds in the Fatty Acid Chain
•Omega number represents location of the closest double bond from methyl end (CH3)
•Linolenic acid
•18:3 ω-3 (or 18:3 n-3)
•Monounsaturated fatty acids
•Omega-9 group
\.Characteristics of Solid Fats and Oils: Chemistry influences the fats and oils in food:
firmness
Stability
\/•Firmness:
•Most polyunsaturated are liquid at room temp
•Saturated animal fats are solid at room temp
Some fats (e.g., cocoa butter, palm oil, coconut oil) are firmer than vegetable oils because of
saturation, but softer than animal fats because of shorter carbon chains
,\.•Stability:
•Oxidation produces compounds that smell and taste rancid
•Three ways to combat rancidity
\.Trans-Fatty Acids
Avoid this as much as possible
CIS FATTY ACIDS
TRANS-FATTY ACIDS
\.Cis Fatty Acids
•Hydrogens on same side of double bond; cis molecules bend into U-like formation
•Most naturally occurring unsaturated FAs are cis
\.Tran fatty acids
•Hydrogens on opposite sides of double bond; trans molecules are more linear
•Forms during hydrogenation
\.Knowledge Check
1.Having too much or too little fat can lead to good/poor health.
2.Fatty acids always have an even/odd number of carbons.
3.Triglycerides consist of a _GLYCEROL_ and three fatty acid tails.
4.Unsaturated fats are called such because: They have a double bond.
\.Which fatty acids tend to be solid at room temperature? Unsaturated or saturated?
saturated
\.Trans fats tips and tricks
Nutrion panel
-Trans fats can be counted as no trans fats if it has 0.5 grams of trans fats per serving
-Partial hydrogenated or hydrogenated fats is is an indicator of trans fats
\.Phospholipids
,•Solubility in fat and water
•Emulsifiers in food industry
•Lecithin is best known
•Food sources
•Roles
−Part of cell membranes
−Used as Emulsifiers to make food more appealing, also avt like that in our body
\.Sterols food sources
−Cholesterol
−Plant sterols
\.Cholesterol is only found in
animal products
\.•Roles of sterols
−Made in the body
−Structural component of cell membranes
\.Do peanuts have cholesterol?
no, it is a plant product
\.Diet cholesterol is diffeerent than are
cholesterol in our body, also like 96 % of our body is triglycerides
\.1.Describe the difference between cis- and trans-fatty acids.
u vs linear
\.Which of the following are true of sterols? Phospholipids?
Cholesterol
Vitamin D
Structural component in cell membranes
\.Fat Digestion in the GI Tract
, Vast majority of fat ingestion is the small intestine (some can be in the mouth)
Large intestine = come fat and cholesterol
\.Lipid Digestion
•Mouth
•Lingual lipase plays role in fat digestion in infants
•Stomach
•Strong muscle contractions
•Gastric lipase
\.Lipid Digestion in the Small Intestine
•Cholecystokinin (CCK)
•Pancreatic lipase
•Hydrolysis
•Bile routes
•Cholecystokinin (CCK)
•Gallbladder releases bile
•Bile acts as emulsifier
•Hydrolysis
•Triglycerides and phospholipids
•Bile routes
•Effect on blood cholesterol levels
Dietary cholesterol can be used as
bile and be recycled?
Lipid Absorption Lymphatic system
•Micelles diffuse into intestinal cells
•Reassembled into triglycerides
•Packed with proteins into transport vehicles called chylomicrons