Week 5 Flashcards
Glycoside
A glycoside is a sugar molecule, a saccharide. Can form glycosidic bonds
Reducing sugars
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.
Aldonic acid
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
Adonolacetone
This happens when an aldose and a ketose comes together?
Uronic acid
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
Reduction
a reduction is where a proton is transferred to reduce the charge of another compound
Sugar Alcohol
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
esterification
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.
Etherification
Etherification is a dehydration of alcohols to form ethers. An ether is an oxygen connected to two other things
Nonenzymatic browning
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
Schiff base
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.
Amadori rearrangement
After the Schiff base is made, an isomerization reaction happens to make the molecule a ketose
Furfural
A furfural is a five atom ring with a separate aldehyde group on one side. They are a product of the Maillard reaction.
Strecker degradation
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Melanoidins
These are large polymers of intermediates made from step 2 in the Maillard reaction. These are responsible for the brown coloring
Caramelization
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
Acrylamide
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.
Oligosaccharide
these are polymers of saccharides that are between 2 and 20 units long
Glycosidic linkage
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.
Maltose
Maltose is a disaccharide made of glucose and glucose. It is bound by an alpha 1-4 glycosidic bond
Lactose
A disaccharide comprised of glucose and galactose with a beta 1-4 glycosidic bond
Surcrose
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
cyclodextrin
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
Polysaccaride
This is a chain of monosaccharide units bound together by glycosidic bonds.
Degree of polymerization
This described how many monomers there are in the chain or the length of the chain.
Molecular weight
This describes the weight of the polysaccharide
Molecular size
This describes how much space the polysaccharide takes up in its environment.
Polymolecular
Having multiple molecules in a particular system. This could be like with starch, there are many molecules of amylose and amylopectin
Polydisperse
A colloidal dispersion with a range of particle sizes
Heteroglycan
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.
Homoglycan
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.
Linear
This describes the bonding behavior of a polysaccharide to produce a chain that is relatively straight and does not fold back on itself.
Copolymer
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.
