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Lecture 6
FDSN 507 Midterm 1
Esters of fatty acids, and monoglycerides are examples of ____ lipids. | simple |
Phospholipids, lipoproteins, and glycolipids are examples of _____ lipids. | compound |
Free fatty acids, long chain alcohols, hydrocarbons, and fat soluble vitamins are examples of ____ lipids. | derived |
Name three ways of preparing samples for lipid analysis. | Predrying, particle size reduction, acid hydrolysis |
What is the purpose of predrying for lipid analysis? | Breaks emulsions, helps free fat from tissue |
_____ ____ breaks both covalently and ionically bound lipids | acid hydrolysis |
Give four properties of a good solvent. | Low boiling point, non-flammable, inexpensive, low solvent power for proteins/carbohydrates, nonhygroscopic |
____ ____ is a good solvent for fat, but is more expensive and hygroscopic than _____ _____. | ethyl ether, petroleum ether |
Define gravimetric analysis. | Measurement of fat content by fat removal from sample. |
T or F: The Mojonnier method involves use of a series of solvents. | True |
T or F: For the Mojonnier method, it is necessary to first remove all moisture from the product. | False |
Supercritical fluid extraction involves elevated ____ and _____, with _____ decreasing. | pressure, temperature, pressure |
Accelerated solvent extraction involves elevated ____ and _____. | pressure, temperature |
The AOAC method for total fat determination is by ______. | Hydrolytic Extraction Gas Chromatographic Method |
____ acid can be used in gas chromatography to minimize oxidative degradation of fatty acids. | Pyrogallic |
____ is added as an internal standard in gas chromatography. | triglyceride |
What three methods can be used to extract fat with ether? | Soxhlet, Goldfish, Mojonnier |
____ ____ is used to separate and quantify different fatty acid methyl esters. | Gas chromatography |
The _____ method is a non solvent wet extraction method. | babcock or gerber |
In the babcock method, _____ acid digests protein, generates heat, and releases fat. | sulfuric |
What is the difference between the babcock and gerber methods? | Amyl alcohol is also used in the babcock method. |
qWhat is the purpose of isoamyl alcohol in the gerber method? | Prevents the charring of sugar |
What type of IR is used for milk fat? | Mid |
Describe the Foss-Let method. | Fat is determined as a function of the specific gravity of a sample solvent extract. |
What is the advantage to using NMR to analyze fat? | nondestructive |