Enzymes food application Flashcards
describe amylose structure
linear/straight chain
500-2000 units
alpha 1,4 glycosidic linkages
describe amylopectin structure
branched chain
alpha 1, 4 linked glucose branches
alpha 1,6 branch point linkages
describe starch hydrolysis in acidic conditions
random pattern
describe starch hydrolysis through enzymatic conditoins
conntrolled attack
what does thermostable alpha amylase turn starch into
dextrins
branched and linear oligos
what does thermostable CGTase turn starch into
cyclodextrins
how do dextrins turn into maltose + maltotriose
fungal alpha amylase
two stages of turning starch into sugar
liquefaction
saccharfication
enzymes that turn dextrins into glucose + high glucose syrup
amyloglucosidase
pulluanase
enzymes that turn dextrins into maltose + high maltose syrup
pullaulanase
beta amylase
how to turn glucose + high glucose sugar into crytalline sugar
crystalisation
what does glucose isomerase turn glucose + high glucose syrup into?
fructose syrup
describe liquefaction
enzyme cuts long chain of starch into dextrins or cyclodextrins depending on the enzyme added
what must happen to the starch before liquefaction
must gelatinise in order for amylase to be able to attack it
Pectinmethylesterase carrie out what type of reaction
hydrolysis
what part of pectin does PMe attack
methyl group
products PME and Pectin
methanol
polygalacturonic acid
what happens to the polygalactoronic acid after hydrolysis
attacked by another enzyme
polygalacturonase
product of polygalacturonase activity
shorter chain sugar
other enzymes that breakdown shorter chain
pectin lyase
what does PME do by removing the methyl group from pectin
creates a negative charge
how does calcium bind to the hydrolysed pectin
the negative charge left by removing the methyl group allows calcium to bind
what happens when pectin (only homogalacturonan) undergoes b-elimination at >80C and ph >4.5
texture/viscosity loss
what happens when pectin (only homogalacturonan) undergoes hydrolysis by PME
same as in carrots, results in a product with negative charge.
what can the product produced by PME react with in tomatoes
calcium: improved texture
PG and acid hydrolysis (ph<3): texture loss but improved juice extraction
PL: tecture and viscosity loss
