Carbohydrates Flashcards
Sugars
Monosaccharides
Disaccharides
Sugar properties
Soluble in water
Sweet
Water activity mono vs disaccharides
Despite having the same impact on blood sugar
Monosaccharides have a double effect per gram on water activity.
Two available areas for water to bind
Oligosaccharides
3-10 units
High concentration of them increases viscosity
Can not be broken down in our body
Broken down by microbiome in large intestine
Polysaccharide
> 10 units
Not soluble
If in boiling water it will swell
Taste overview
Sensing concentrations of specific chemicals dissolved in the saliva. Receptor cells generate signals to the brain, which integrates signal sensing different chemicals.
Sweet taste receptor
Bind to T1R2 and T1R3
Transmit signal to target enzyme phospholipase C through GTP binding signal
This signal causes calcium to bind to TRPM5
TRPM5 activated
Sodium enter cell causing depolorisation
UMAMI taste
Links to speciifc amino acids
Glutamic acid and monosodium glutamate
UMAMI receptors
T1R1 and T1R3 receptor
Same cascade as sweet
Nervous signal in brain
Signals that we are doing something good
Reward pathway
Sweetener vs sugar
When sweetener binds to receptor causes same cascade
However, not nutritionally useful so does not have the double stimulation of actually being carbohydrate
Not as good feeling when eating it
Evolutionary point - made us eat more of what we could actually use for energy
Receptor Binding
The sugar or amino acid can either bind to the receptor strongly or weakly
Also things that block the receptor
Functional properties of carbohydrates
Have lots of OH groups
Allows them to make hydrogen bonds with water
Requires lots of energy to dry
Sugar solutions turn to caramel so can not be dried unless form sugar crystals
Maillard Reaction
Sugar combined with amino acids creates brown colour.
Amine group on AA and hydroxyl group on anomeric Carbon
Create roasted flavour
Caramel Potato crisps Brown sugar Coffee Dark beer Glazed meet
