Qualitative Food Tests
Name: Marcus Gonzales
Date: Wednesday 12th September 2012
Form: L62
Subject: Biology
Teacher: Ms. Hutton
Lab #: 1
Title: Food Tests
Aim: To test an unknown substance for various food substances.
Apparatus/Materials:
* Unknown Solution X * NaOH * Iodine * Ethanol * Copper Sulphate * Benedict’s Solution * HCl * Cold Water * Syringe * Beakers * Bunsen burner * Tripod stand * Test tubes * Dropper
Introduction: This Lab shows the detection of different food sources using different tests. Some of the food tests carried out was Benedict’s test, the test for non-reducing sugars, iodine test (test for starches), emulsion test and the biuret test.
Carbohydrates include reducing and non-reducing sugars also starches. They have a general Formula of CnH2nOn.They can be classified into three main groups, Monosaccharide, Disaccharide and polysaccharide. Carbohydrates have many uses such as: for energy, for storage of food in both plant and animal cells e.g. Starch, chloroplasts, for structure in plant cells e.g. cellulose have a structural use in plant cell walls giving it structure. Carbohydrates are sweet and soluble in water with the only exceptions of starch and cellulose. Reducing sugars react with the copper in Benedict’s reagent to form a brick-red precipitate. Non-reducing sugars however do not react with Benedict’s reagent because the part that would react with the Benedict’s reagent is already in a glycosidic bond with another molecule. Therefore it is heated with HCl to break these bonds so that the benedict’s solution can be effective. Starch is made up of amylose and amylopectin, it is used as storage for food made in plants.
Lipids can be classified as fats, oils, or anything similar to a fat/oil that is insoluble in water. There are different types of Lipids such as: Saturated, unsaturated, triglycerides and phospholipids Lipids are non-polar and insoluble in water. They are made
Date: Wednesday 12th September 2012
Form: L62
Subject: Biology
Teacher: Ms. Hutton
Lab #: 1
Title: Food Tests
Aim: To test an unknown substance for various food substances.
Apparatus/Materials:
* Unknown Solution X * NaOH * Iodine * Ethanol * Copper Sulphate * Benedict’s Solution * HCl * Cold Water * Syringe * Beakers * Bunsen burner * Tripod stand * Test tubes * Dropper
Introduction: This Lab shows the detection of different food sources using different tests. Some of the food tests carried out was Benedict’s test, the test for non-reducing sugars, iodine test (test for starches), emulsion test and the biuret test.
Carbohydrates include reducing and non-reducing sugars also starches. They have a general Formula of CnH2nOn.They can be classified into three main groups, Monosaccharide, Disaccharide and polysaccharide. Carbohydrates have many uses such as: for energy, for storage of food in both plant and animal cells e.g. Starch, chloroplasts, for structure in plant cells e.g. cellulose have a structural use in plant cell walls giving it structure. Carbohydrates are sweet and soluble in water with the only exceptions of starch and cellulose. Reducing sugars react with the copper in Benedict’s reagent to form a brick-red precipitate. Non-reducing sugars however do not react with Benedict’s reagent because the part that would react with the Benedict’s reagent is already in a glycosidic bond with another molecule. Therefore it is heated with HCl to break these bonds so that the benedict’s solution can be effective. Starch is made up of amylose and amylopectin, it is used as storage for food made in plants.
Lipids can be classified as fats, oils, or anything similar to a fat/oil that is insoluble in water. There are different types of Lipids such as: Saturated, unsaturated, triglycerides and phospholipids Lipids are non-polar and insoluble in water. They are made