Comparison of Chemical Composition of Various Food Stuff

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Title : Comparison of Chemical Composition of Various Food Stuff

Introduction

Carbohydrate is a macromolecule that consists of atoms of carbon, hydrogen & oxygen. The carbohydrates or saccharides exists in 4 groups, monosaccharides, disaccharides, oligosaccharides and polysaccharides. Starch is among one of the polysaccharides and it consists of a large number of units of glucose molecules joined together by glycosidic bonds. Starch consists of two types of molecules , the linear and helical amylose and the branched amylopectin. Potatoes have large amount of starch as it is a staple food. The starch in potato can be tested by the iodine test. When starch is present, the iodine will turn purplish black in colour.

Benedict’s solution is used to test the presence of reducing sugar. All monosaccharides are reducing sugars since all of them have an active carboxyl group. The example of reducing sugars are glucose, fructose, lactose and maltose. Some disaccharides that are exposed to a carboxyl group are also reducing sugar, but less reactive than monosaccharides. By mixing the sugar solution solution with Benedict’s solution and heating them under water bath of 80℃, a redox reaction will occur. The copper(II) sulphate present in Benedict’s solution which exists as light blue in colour reacts with electron from aldehyde or ketose group of reducing sugars to form copper oxide, which is a brick-red precipitate.

The purpose of doing Benedict’s test is to detect the presence of reducing sugar in a substance. Benedict’s solution, which is the reagent for the test will detect the presence of aldehydes and alpha-hydroxy-ketones. If positive result is shown when Benedict’s test was conducted, the substance will change in colour from c...

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9. http://zoologistbd.blogspot.com/2012/04/benedicts-test-for-reducing-sugars.html

10. Omar Nahhas, Yahoo Contributor Network ( 22 July, 2009 ). Retrieved 15 May 2014, from http://voices.yahoo.com/the-chemical-constituents-living-matter-3856864.html

11. Retrieved 15 May 2014, from http://en.wikipedia.org/wiki/Protein

12. Retrieved 15 May 2014, from http://ansci.illinois.edu/static/ansc438/Milkcompsynth/milkcomp_protein.html

13. Jones, M. & Taylor, D. (2007). AS Level and A Level Biology: Second Edition. Cambridge: Cambridge University Press.

14. Starch,retrieved 18th May 2014. http://en.wikipedia.org/wiki/Starch

15. Iodine test,retrieved 18th May 2014. http://en.wikipedia.org/wiki/Iodine_test

16. Retrieved 18th May 2014. http://www.elmhurst.edu/~chm/vchembook/547starch.html

17. Retrieved 18th May 2014. http://en.wikipedia.org/wiki/Carbohydrate

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