this is all about carbohydrates determination only...
2007-02-18 22:39:14 · 5 answers · asked by laila grace m 2 in Science & Mathematics ➔ Chemistry
Actually I can not -- but thank you for asking!
2007-02-18 22:43:07 · answer #1 · answered by Heidi A 3 · 0⤊ 1⤋
Typically this is done with Benedict's reagent. The color after heating can be linked to the concentration of reducing sugar. Below are a couple of links that may help you understand the chemical reactions taking place.
2007-02-19 07:00:02 · answer #2 · answered by jas 2 · 0⤊ 0⤋
Lancenigo di Villorba (TV), Italy
YOUR QUESTION INTERESTS A VERY LARGE SPECTRUM.
ABOUT REDUCING SUGARS
I remember you that reducing sugars are carbohydrates able to undergo chemical or biological oxidation phenomena.
In the lab's surroundings, "reducing sugars" preserve one its own carbonylic functional group as able to react with someones oxidizing reactives.
Since carbohydrates are distinguished between mono-and poly-saccharides, I remember you the latter are formed by means of glycosidic bond (e.g. ether's nature, -C-O-C-) between more saccharidic units. The latter bonds may involve carbonylic group of its forming units, since they are excluded by common oxidative events. These latters are carbohydrates not reducing ones, e.g. sucrose in sugar's cane.
You may think mono-saccharides (e.g. glucose in honey) are the lonely reducing sugars, starting from the fact they involve not any glycosidic bonds. Nonetheless, they exist many reducing sugars other than monosaccharides ones, e.g. lactose of milk.
LAB's ESSAYS
Mainly, I show you the copper ion-based stuffs.
BARFOED
You add Glacial Acetic Acid (e.g. pure Ethanoic Acid) in deionized water's amount, hence you dissolve in this solution some spoons of copper acetate. This reactive receive the carbohydrates and you mix them in warm-bath conditions.
ONLY MONOSACCHARIDE ONES GIVE POSITIVE REMARKS. WHAT DO I SEE? Few minutes need to overwritten type of sugars to form brown powder (e.g. Cu2O, cuprous oxide).
BENEDICT/von FEHLING
You add some spoons of salt of some organic oxy-acids (e.g. citrate or tartrate) in a dilute copper sulphate's solutions, hence you dissolve in this solution some drops of sodium hydroxide stuff. This reactive receive the carbohydrates and you mix them in warm-bath conditions.
REDUCING ONES GIVE POSITIVE REMARKS. WHAT DO I SEE? Few minutes need to overwritten type of sugars to form brown powder (e.g. Cu2O, cuprous oxide).
BIAL
You add some spoons of orcinol (e.g. 3,5-dihydroxy-toluene) in strong solution of hydrochloric acid. This reactive receive the carbohydrates and you mix them in warm-bath conditions.
FURANOSE ONES GIVE POSITIVE REMARKS IN FASTEST WAY. WHAT DO I SEE? Few minutes need to overwritten type of sugars to form greenish hue, a paler hue in PYRANOSE's cases.
SELIVANOFF
You add some spoons of resorcinol (e.g. 1,3-dihydroxy-benzene) in strong solution of hydrochloric acid. This reactive receive the carbohydrates and you mix them in warm-bath conditions.
KETOSE ONES GIVE POSITIVE REMARKS IN FASTEST WAY. WHAT DO I SEE? Few minutes need to overwritten type of sugars to form reddish hue, aldose ones do not.
STARCH
Amilose is the water-soluble fraction of starch. It is a macro-molecule interacting with molecular iodine, forming a black-bluish coloured complex.
Lugol's stuff undergoes dilution in deionized water.
I hope this helps you.
2007-02-19 07:29:38 · answer #3 · answered by Zor Prime 7 · 0⤊ 0⤋
formal report?
hehehe.
wala talaga mahanap..asa pa tau!
2007-02-20 04:32:49 · answer #4 · answered by Benjamin III T 1 · 0⤊ 0⤋
diet control
2007-02-27 00:48:21 · answer #5 · answered by mysore s 2 · 0⤊ 0⤋