food aos Flashcards
define gi
The glycaemic index (GI) of a food is a measure of how quickly blood glucose (blood sugar) levels increase after the food is consumed.
HIGH - rapid increase in blood glucose
GI of amylose
Amylose has a linear and coiled structure that allows it to pack efficiently. This reduces exposure of it’s OH groups for solubility and reduces access for enzymes to hydrolytic sites. This results in a low GI
GI of amylopectin
Amylopectin has a branched structure that prevents efficient packing of molecules. This increases exposure of it’s OH groups for solubility and increases access for enzymes to hydrolytic sites. This results in a high GI
types of bonds in each protein sturcture)primary/…)
primary: covalently bond with peptide bonds
secondary: primary consisting of hydrogen bonding from amine and carboxyl groups, disulfide bridges
tertiary: all intermolecular forces, dispersion, dipole dipole, ion dipole, ionic bonding.disulfide bridges
quaternary: through cystime mino acids, other itnermolecular forces
hydrolysis of protein
shorter polypeptides to dipeptides to amino acids
- hydrolysis
hydrolysis of carbs
amylase breakds down carbs into smaller disaccarides in the mouth
in the small intestine, further broken to monosaccharise adn break gylosidic link.
hydrolysis of fats
First stage: Emulsification → Bile breaks down large fat globules into smaller fat droplets
Second stage: Hydrolysis → Lipases hydrolyse the triglycerides into 3 fatty acids and a glycerol molecule
stereoisomers
stereoisoamre: molecules with same molecular formula but different sptial arragments of atoms, can’t be super imposed
gemometri isomers: trans and cis, double cc
optical: chiracal enters, enantiomer
how triglyceride is made
glycerol + fatty acid equals triglyceride and water
oxidative rancidity
more c double c more change of axadative rancidity
