Chemistry Project Class 12 1m1l67

BIBLIOGRAPHY: 1) NCERT Class XII Text Book for Chemistry 2) Chemistry Laboratory Manual Class XII, APC Publications 3) www.idoub.com 4) www.scholastic.com

ACKNOWLEDGEMENT

I would like to thank my teacher for her valuable guidance .I would also like to thank my parents for their and patience, also I am indebted to my friend and classmates for helping me out in the preparation of the project .Once again my sincere thanks to everyone involved as this project would not have been possible without their contribution.

AIM: To determine glucose content in different biscuits (preferably of different brands).

MATERIALS REQUIRED: Sample of biscuit, Pestle and mortar, Test tube, Tripod stand, Benedict’s reagent, Fehling’s reagent

THEORY: When we think of sugar we probably picture the white granules you put in cookies, that your parents put in coffee, or that you put on your cereal. Actually this is just one kind of sugar, called sucrose, which is extracted from sugar cane or sugar beets. Technically sugar is a carbohydrate that occurs naturally in every fruit and vegetables. It is the major product of photosynthesis, the process by which plant transform sun’s energy into food. Glucose is another type of sugar and is very important biochemical. For one thing glucose is the only fuel used by brain cells. Glucose is also an important source of energy for muscle and other tissue in the body. The glucose in your blood comes from food you eat. Complex carbohydrates found in pasta or cereals, for example are long chains of sugar molecules that are broken down by enzymes to simple sugars, such as glucose. Sucrose or table sugar is also broken down to form glucose. Because carbohydrates and sucrose in food are broken down to form glucose, the level of glucose in our blood goes up after you eat. Like most of the chemicals in your blood, the level of glucose must be tightly controlled .The level of glucose in your blood is controlled by insulin, a hormone made in the pancreas. Too little glucose and your brain and other organs will not have the energy they need to function .too much glucose in the blood can cause diabetes, which is a serious and growing health problem in world. Food product can be tested to determine whether they contain reducing sugars through test known as Benedict’s test or Fehling’s test .these test can also be used to determine if sugar is present in certain bodily fluids, such as urine, which is important for diagnostic testing.

WHAT IS A REDUCING SUGAR? Any sugar that forms an aldehyde or ketone in the presence of an alkaline solution is a reducing sugar. Types of reducing sugars include glucose, fructose, glyceraldehydes, lactose, arabinose and maltose.

BENEDICT’s TEST To test the presence of reducing sugars, a food sample is dissolved in boiling water. Next a small amount of Benedict’s reagent is added and the solution begins to cool. During next 4-10 minutes the solution should begin to change color. If the color changes to blue ,then no glucose is present .If a high amount of glucose is present, then color change will progress to green, yellow, orange, red and then a dark red or brown.

FEHLING’S TEST To carry Fehling’s test, the solution is diluted in water and warmed until fully dissolved .Next, Fehling’s solution is added while stirring. If reducing sugars are present, the solution should begin to change color as rust or red colored precipitate forms. If reducing sugars are not present, the solution will remain blue or green.

PRACTICAL APPLICATION Reducing sugar test such as Benedict’s test and Fehling’s test can be used to determine whether sugars are present in urine, which can be indicative of diabetes mellitus they can also be used in a qualitative manner such as in titration experiment, to determine the amount of reducing sugar in solution .

PROCEDURE 1. Take sample of biscuit and crush it 2. Take 5ml of solution of Fehling’s reagent in a test tube. 3. Add 2-3 grams of the crushed sample of biscuits and add to the solution 4. Put the test tube in water bath 5. Repeat this for Benedict’s test.

OBSERVATIONS Benedict’s Fehling’s

Mcvities Mustard Brown

Happy Happy Dark Mustard Mustard Brown

Britania Brownish red Dark brown

INFERENCE Britania contain the maximum amount of glucose followed by Mcvities, Britania contains the least glucose of all the three

Precautions: 1. Weighing of the sample and reagents should be accurately done 2. Rinse the test tube properly 3. Test tube should not be disturbed till the color changes 4. Take down the color readings from the sample carefully from the color scale provided on the reagent bottle.