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===Meaning===
Use a range of tests to identify the presence of [[Carbohydrate]]s, [[Protein]]s and [[Lipid]]s in food samples.
===Methods=======Testing For Monosaccharides====: [[Monosaccharide]]s can be detected with the [[Benedict's Test]].: [[Disaccharide]]s cannot be detected with the [[Benedict's Test]] unless you first react it with dilute [[Hydrochloric Acid|hydrochloric acid]].=====Method=====#A sample of food is dissolved in water.#The solution is added to blue Benedict's solution in a boiling tube.#The solution is kept at 90°C for up to 10 minutes.#A colour change indicates the presence of [[glucose]] or [[fructose]]. If they are present the solution will eventually turn brick red or brown.{| class="wikitable"|-*|[[Dependent VariableFile:BenedictsTest.png|center|600px]] |-| style="height:20px; width:600px; text- align:center;" |When sugar is present the Benedict's solution turns from blue through several colours until it becomes brick red or brown.If this was done with sucrose the Benedict's solution would stay blue.|} *====Testing for Starch====: [[Independent VariableStarch]] can be detected using Iodine Solution.=====Method=====#A small sample of food is placed on a spotting tile.#A drop of Iodine Solution is added to the food sample.#If the Iodine solution turns from orange to blue-black then the food contains [[starch]].{| class="wikitable"|- *|[[Control VariableFile:IodineStarch.png|center|400px]]s |-| style="height:20px; width:400px; text-align:center;" |Iodine solution is an orange liquid. When the iodine solution is added to starch the iodine solution turns from orange to blue- black.#|}