EX 4 TEST RESULTS Flashcards
STARCH
amylose gives a ____ color with iodine soln
BLUE
STARCH
amylopectin gives ____ color with iodine soln
VIOLET
STARCH
dextrin gives ____ color if it is ____ with iodine soln
red, partially hydrolyzed
STARCH
a polysaccharide that does not form colored complexes with iodine soln
cellulose
starch granules ____ and ____
swell and burst
starch liquid ____ and ____
thickens & gelatinized
STARCH | pH
corn starch
neutral
STARCH | pH
wheat starch
neutral
STARCH | pH
rice starch
alkaline
STARCH | pH
potato starch
acidic
Glycogen yields ____ color with iodine
reddish brown
TEST FOR CARBOHYDRATES | TEST RESULT
Molisch test
red/purple ring at the junction
TEST FOR CARBOHYDRATES | REAGENT
Molisch test
a-naphthol with conc. H₂SO₄
TEST FOR CARBOHYDRATES | TEST RESULT
Fehling’s test result for glucose & fructose
BRICK RED
TEST FOR CARBOHYDRATES | REAGENT
Fehling’s B
sodium potassium tartrate (rochelle’s salt)
TEST FOR CARBOHYDRATES | TEST RESULT
Bial’s test
bluish green w/o ppt
TEST FOR CARBOHYDRATES | REAGENT
Fehling’s A
copper sulphate
TEST FOR CARBOHYDRATES | TEST RESULT
Benedict’s test
blue
green
yellow
orange
brick red
general test for carbohydrates
MOLISCH TEST
test for reducing sugars
Fehling
Benedict
TEST FOR CARBOHYDRATES | TEST RESULT
Barfoed’s test
light red ppt
TEST FOR CARBOHYDRATES | TEST RESULT
Fehling’s test result for saccharose
blue
TEST FOR CARBOHYDRATES | TEST RESULT
BARFOED’S:
disaccharides produce the red ppt in how many mins
10mins
test for pentoses
bial’s orcinol test
furfural test
test to distinguish between monosaccharides and disaccharides
Barfoed’s test
heat a solution of the substance in a test tube with an equal volume of HCl containing orcinol and ferric ions
Bial’s orcinol test
TEST FOR CARBOHYDRATES | TEST RESULT
BARFOED’S:
monosaccharides produce the red ppt in how many mins
2-3 mins
TEST FOR CARBOHYDRATES | REAGENT
Barfoed’s test
copper acetate in acetic acid
not a reactive as benedict’s reagent
TEST FOR CARBOHYDRATES | TEST RESULT
OSAZONE:
glucose & fructose
needle-like
TEST FOR CARBOHYDRATES | TEST RESULT
OZASONE:
maltose
sunflower
TEST FOR CARBOHYDRATES | TEST RESULT
OSAZONE:
lactose
cotton ball
heating a sugar solution with phenylhydrazine HCl, sodium acetate and acetic acid
Osazones
test for ketoses
Seliwanoff’s test
TEST FOR CARBOHYDRATES | TEST RESULT
Osazone formation
yellow crystals
TEST FOR CARBOHYDRATES | TEST RESULT
OSAZONE:
galactose
thorny ball
a crystal of resorcinol is added to the solution and warmed on a water bath with an equal volume of conc. HCl
Seliwanoff’s test
test for deoxysugars
Keller-kiliani
TEST FOR CARBOHYDRATES | TEST RESULT
SELIWANOFF:
aldohexose
light pink
TEST FOR CARBOHYDRATES | TEST RESULT
Keller-kiliani test
reddish brown
TEST FOR CARBOHYDRATES | TEST RESULT
SELIWANOFF:
ketohexose
deep red
a deoxysugar is dissolved in acetic acid containing trace of ferric chloride and transferred to the surface of conc. H₂SO₄
Keller-kiliani
- a carbohydrate sample is heated in a test tube with a drop of syrupy phosphoric acid to convert it into furfural
- a disk of filter paper moistened with a drop of 10% soln of aniline in 10% acetic acid is placed over the mouth of the test tube. the bottom of the test tube is heated for 30-60s
furfural test
%yield for pectin
wt of pectin / wt of the mesocarp x 100
TEST FOR CARBOHYDRATES | TEST RESULT
Furfural test
pink or red stain
