Week 5

Question 1

Glycoside

Answer 1

A glycoside is a sugar molecule, a saccharide. Can form glycosidic bonds

Question 2

Reducing sugars

Answer 2

A reducing sugar has the ability to be oxidized and thus reduce another compound. This is able to happen because the sugar has a hemiacetal end or an open end for bonding to occur. Glucose and lactose are reducing sugars because they have 1-4 hemiacetal bonds. Sucrose however is lined up head to head with a 1-6 acetal bond which does not allow for reduction or oxidation.

Question 3

Aldonic acid

Answer 3

An aldonic acid is an aldose which has been tautomerized to have an acid group on the aldehyde group. This turns the aldehyde into a carboxylic acid group

Question 4

Adonolacetone

Answer 4

This happens when an aldose and a ketose comes together?

Question 5

Uronic acid

Answer 5

Uronic acid is made by changing the CH2OH group into a carboxylic acid group at the end of a molecule. This can be done on any saccharide molecule

Question 6

Reduction

Answer 6

a reduction is where a proton is transferred to reduce the charge of another compound

Question 7

Sugar Alcohol

Answer 7

a sugar alcohol is a sugar molecule with one hydroxyl molecule attached to every carbon. A saccharide unit can be made into an alcohol by changing the carboxyl group to a carboxylic acid

Question 8

esterification

Answer 8

This is where an acid reacts with an alcohol, the OH of the acid combines with the H of the alcohol to form a water molecule. This is a dehydration reaction that results in an ester. An ester is a carboxylic acid group that is attached to two other components.

Question 9

Etherification

Answer 9

Etherification is a dehydration of alcohols to form ethers. An ether is an oxygen connected to two other things

Question 10

Nonenzymatic browning

Answer 10

Nonenzymatic browning happens when a reducing sugar and an amino group come together to form different compounds that ultimately form different colored and flavored things

Question 11

Schiff base

Answer 11

A Schiff base is made when a reducing sugar and an amino group come together. The amino group attached to the hemiacetal end. The oxygen is replaced by the nitrogen of the amino group.

Question 12

Amadori rearrangement

Answer 12

After the Schiff base is made, an isomerization reaction happens to make the molecule a ketose

Question 13

Furfural

Answer 13

A furfural is a five atom ring with a separate aldehyde group on one side. They are a product of the Maillard reaction.

Question 14

Strecker degradation

Answer 14

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Question 15

Melanoidins

Answer 15

These are large polymers of intermediates made from step 2 in the Maillard reaction. These are responsible for the brown coloring

Question 16

Caramelization

Answer 16

This is where sugar is heated but it requires temperatures of 165 degrees C or higher. Sucrose can also participate in this type of browning

Question 17

Acrylamide

Answer 17

Acrylamide is made when an intermediate of stage 2 of the Maillard reaction separates back out from the amino group and the sugar. This happens especially when asparagine is used as the amino acid and when high temperatures are used.

Question 18

Oligosaccharide

Answer 18

these are polymers of saccharides that are between 2 and 20 units long

Question 19

Glycosidic linkage

Answer 19

This is the linkage through which monosaccharide units are bound together. These can be up or down depending on the anomeric configuration. They can also be bound in a way that encourages a straight organization or a more disordered one.

Question 20

Maltose

Answer 20

Maltose is a disaccharide made of glucose and glucose. It is bound by an alpha 1-4 glycosidic bond

Question 21

Lactose

Answer 21

A disaccharide comprised of glucose and galactose with a beta 1-4 glycosidic bond

Question 22

Surcrose

Answer 22

A disaccharide molecule comprised of fructose and glucose molecules bound together by an alpha 1-2 glycosidic bond. This bond is a head to head bond that causes the sugars to go down in a vertical manner rather than the usual horizontal

Question 23

cyclodextrin

Answer 23

These are rings of glucose formed by alpha 1-4 glycosidic bonds. The way that the bond occurs influences the way that the individual monomers make up a larger chain. Amylose for example has this structure with an alpha 1-4 glycosidic bond which causes the larger secondary structure to be an alpha helix

Question 24

Polysaccaride

Answer 24

This is a chain of monosaccharide units bound together by glycosidic bonds.

Question 25

Degree of polymerization

Answer 25

This described how many monomers there are in the chain or the length of the chain.

Question 26

Molecular weight

Answer 26

This describes the weight of the polysaccharide

Question 27

Molecular size

Answer 27

This describes how much space the polysaccharide takes up in its environment.

Question 28

Polymolecular

Answer 28

Having multiple molecules in a particular system. This could be like with starch, there are many molecules of amylose and amylopectin

Question 29

Polydisperse

Answer 29

A colloidal dispersion with a range of particle sizes

Question 30

Heteroglycan

Answer 30

When a polysaccharide contains more than one type of monosaccharide unit. For example, guar gum is a galactomannan which consists of galactose and mannose monosaccharide units.

Question 31

Homoglycan

Answer 31

A homoglycan is a polysaccharide with only one type of monosaccharide. An example of this would be amylopectin which is made up only of glucose units.

Question 32

Linear

Answer 32

This describes the bonding behavior of a polysaccharide to produce a chain that is relatively straight and does not fold back on itself.

Question 33

Copolymer

Answer 33

This is where more than one monosaccharide units are reacted together to form a different organization of the chain. It can be alternating with every other unit, it can be in block formation, or it can be in random order.