Triglycerides

Question 1

Animal fat is solid because: 
A.	It has a higher ratio of
di-saturated (gs2u) and
tri-saturated (gs3) glycerides
B.	It has higher amount of saturated fatty acids than unsaturated ones.

Answer 1

A

Question 2

What is the major FA of cow’s milk?

Answer 2

palmitic acid

Question 3

By increasing the number of double bounds in a fatty acid, its melting point will:
A. Increase
B. Decrease
C. Not be affected

Answer 3

B

Question 4

GS2U means:
A. A TG with two unsaturated fatty acids and one saturated fatty acid
B. A TG with two short chained fatty acids and one unsaturated fatty acid
C. A TG with two saturated fatty acids and one unsaturated fatty acid

Answer 4

C. A TG with two saturated fatty acids and one unsaturated fatty acid

Question 5

T or F : Intraesterification is an exchange of FAs among TG molecules

Answer 5

F

Question 6

The mass of iodine in grams absorbed by 100 g of the sample is:

Answer 6

iodine value

Question 7

What is the simplest form of triglycerides?

Answer 7

the same fa attached to the three positions.

Question 8

T or F : there are no simple analytical methods of separating, isolating and identifying individual triglycerides.

Answer 8

T

Question 9

What are the steps to determine the fatty acid composition of TG

Answer 9

1. saponify with NaOH
2. methylate the FA to convert them to volatile FA methyl esters (FAME)
3. with GA identify against FAME standards

Question 10

What is the group of primary interest for food scientist in north America.

Answer 10

Oleic-linoleic group

Question 11

What are the major fatty acids in milk cow fat?

Answer 11

palmitic acid, oleic acid, mystiric acid, stearic acid.

Question 12

In what category falls these oils : peanut, cottonseed, sunflower, safflower, olive and corn oil?

Answer 12

in the oleic-linoleic acid group

Question 13

T or F : the oleic-linoleic acid group suffers from reversion

Answer 13

false because there is negligible amounts of C18:3é

Question 14

Which group corresponds to this statement : Most oils in this group tend to be categorized as industrial ‘drying oils’

Answer 14

Linolenic acid group

Question 15

To which category corresponds these oils : soybean, linseed, castor, hempseed and perilla oils

Answer 15

linolenic group

Question 16

T or F : the soybean oil is high in omega-3 but is processed (hydrogenation to oleic and linoleic) so that reversion doesn’t occur

Answer 16

true

Question 17

Why is animal fat solid at room temp if it has similar amount of oleic-linoleic than the oleic-linoleic group?

Answer 17

%) but since the glycerol distribution is more GS3 and GS2U than the oleic-linoleic, they are a solid fat rather than an oil.

Question 18

what is the group that contains mustard and rapeseed oil

Answer 18

eruric acid

Question 19

What is the group that the lipoxygenase needs for the oxidation of oils?

Answer 19

cis, cis-1-4-pentadiene group

Question 20

how can you predict the double bonds positions in natural FA if you know only the position of the first double

Answer 20

you know that the most common configuration is the pentadiene, so they will be separated by 3 carbons. (9,12,15).