Carbohydrates Lab Report

Carbohydrates are macronutrients which can be found in all types of food. A carbohydrate molecule contains carbon, oxygen, and hydrogen (Yacoub, n.d.). When found in food, carbohydrates can be starch, sugar, and fiber. Carbohydrates can either have simple or complex forms. For example, glucose, a sugar, is a monosaccharide; these are carbohydrates in their simplest form (Timberlake, 2006). When only a few of these monosaccharide are linked together, they create oligosachharides. If many of the monosaccharides are bonded, they create polysaccharides. These are considered complex carbohydrates. A polysaccharide which is made up of amylose and amylopectin would be starch (Timberlake, 2006). This type of polysaccharide contains many glucose units …show more content…
Using a spot plate, 250 μL, or 5 drops, of the samples from the test tubes were each placed in individual wells. 50 μL or 1 drop of the iodine reagent was added into each of the individual wells containing the samples. There should have been a color change depending if hydrolysis had occurred. One other test involved with hydrolysis is the Benedict’s Test. In each test tube, 2 mL of Benedict’s reagent was added. The test tubes were then heated in a boiling water bath for 3-4 minutes. After the heating, the result of hydrolysis was indicated by a color …show more content…
This was expected as the compounds were monosaccharides (“Types of Sugar : Monosaccharides and Disaccharides”). Monosaccharides are reducing sugars because they either have a free aldehyde or ketone group. Most disaccharides are typically reducing sugars, though there are exceptions, like sucrose. This was seen in the lab as there was no color change, indicating sucrose was not a reducing sugar. This was as well expected since sucrose does not have a free carbonyl group and cannot convert to the open-chain form (Rizzo, 2015). Lactose is also another disaccharide, but one that should be a reducing sugar, as lactose is able to undergo oxidation. The results of the lab specified as such when the lactose sample changed to a red color. Starch is a polysaccharide and the DNSA result indicated it was not a reducing sugar. This was expected because the starch compound should not have had a free carbonyl group. The unknown sample had no color change, which meant it was a non-reducing sugar. The unknown sample had to be either sucrose or

Related Documents