Busy. Please wait.
or

show password
Forgot Password?

Don't have an account?  Sign up 
or

Username is available taken
show password

why


Make sure to remember your password. If you forget it there is no way for StudyStack to send you a reset link. You would need to create a new account.
We do not share your email address with others. It is only used to allow you to reset your password. For details read our Privacy Policy and Terms of Service.


Already a StudyStack user? Log In

Reset Password
Enter the associated with your account, and we'll email you a link to reset your password.
Don't know
Know
remaining cards
Save
0:01
To flip the current card, click it or press the Spacebar key.  To move the current card to one of the three colored boxes, click on the box.  You may also press the UP ARROW key to move the card to the "Know" box, the DOWN ARROW key to move the card to the "Don't know" box, or the RIGHT ARROW key to move the card to the Remaining box.  You may also click on the card displayed in any of the three boxes to bring that card back to the center.

Pass complete!

"Know" box contains:
Time elapsed:
Retries:
restart all cards
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.

  Normal Size     Small Size show me how

FDSN 507 Midterm 2

Lipid Analysis

Physical characteristics, iodine value, saponifcation value, and free fatty acids are all methods to analyze ______. bulk fat or oil
Measuring present status and evaluating stability are methods to analyze _____. lipid oxidation
GC and TLC are methods to analyze _____. lipid fractions
Fat ____ with solvents is typically required before fat _____ if not bulk fat or oil. extraction, chracterization
Name three ways to minimize oxidation of fats. Addition of antioxidants, flush with nitrogen, avoid heat/light.
Name three physical characterization methods for bulk fats and oils. Refractive index, melting point, cold test, cloud point, spreadability.
Solid fat index is measured using _____ and is plotted as ____ vs _____. dilatometry, volume, temperature
Solid fat content is measured using continuous wave or pulsed _____. NMR
_____ can be used to determine the actual percentage of fat in a sample. SFC (solid fat content)
_____ is a measure of degree of unsaturation. Iodine value
Define iodine value. The number of grams of iodine absrobed by 100 g of sample.
_____ gives the average molecular weight of triglycerides in a sample. Saponification value
Define saponification value. The number of mg of KOH required to saponify (give salt and glycerol) 1 g of sample.
_____ measures the fatty acids liberated upon hydrolysis of triglycerides. Free fatty acids
____ are an indication of adequacy of refining. Free fatty acids
____ are the primary products of oxidation. Peroxides
Define peroxide value. Number of mEq of peroxides per 1 kg sample.
A freshly refined or very rancid oil will have a peroxide value of ____. zero
_____ estimates the amount of unsaturated aldehydes (secondary oxidation products) in a sample. p-anisidine value
_____ indicates total oxidation using both peroxide and p-anisidine values. Totox value
_____ is a secondary oxidation product responsible for off flavors/odors. Hexanal
T or F: Lipid extraction is required for hexanal measurement. False
The TBARs test measures a secondary oxidation product known as _____. malonaldehyde
What is the disadvantage of TBARs test? Method is not very sensitive.
T or F: TBARs correlates better with sensory evaluation than peroxide value. True
____ is usually used to measure lipid oxidation in meat products. TBARs test
Conjugated dienes absorb at ____ nm. 232
Conjugated trienes absorb at ____ nm. 270
How should oxidative stability be evaluated? 1. Subject sample to oxygen or heat 2. Monitor oxidation over time with present status test. 3. Determine the induction period before rancidity. 4. Use accelerated shelf-life studies
What can be fractionalized with gas chromatography? Fatty acids, trans isomers, glycerols, cholesterol
What can be fractionalized with IR? Trans isomers
What can be fractionalized with HPLC? Glycerols, lipid soluble pigments/vitamins
What can be fractionalized with TLC? Glycerols
How is Olestra analyzed in lipid fractions? Lipase enzyme is used to breakdown triglycerides and then is precipitated with calcium.
Created by: goberoi