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BIOLOGY COURSEWORK 

Class IX

 TEST FOR STARCH & FATS(i)Test for starch

I have chosen to research and carry out this

e!eri"ent #ecause it is #ased on testin$ food

sa"!les (i%e% !otatoes%) 'hich 'e eat freuently in

"any ty!es lie #oiled "ashed and fried

!otatoes% It is also "y favorite ve$eta#le and I

'ant to no' the a#out the co"!ound !resent in

it%

AIM* To test for starch in the $iven food sa"!le

(!otato)%

APPARATUS REQUIRED* Test+tu#es test tu#estand test tu#e holder s!irit la"! dro!!er ,lter

!a!er Iodine solution distilled 'ater and foodstu- 

(!otato rice 'heat or "ai.e $rains%

THEORY *

Starch a co"!le car#ohydrate is co"!osed of

/01+231 a"ylose and 431+401 a"ylo!ectin% It isfound in di-erent inds of cereals such as rice

'heat "ai.e etc% After reactin$ 'ith iodine

solution starch for"s a dar #lue+#lac co"!ound%

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 The a!!earance of #lue+#lac color is due to the

!resence of a"ylase in starch%

PROCEDURE:

/%Tae a fe' s"all freshly cut !ieces of !otato ora fe' $rains of rice or 'heat or "ai.e in a

clean test tu#e%

2% 5our /3 "6 distilled 'ater into the test tu#e%

7% 8o' #oil the contents of the test tu#e for a#out0 "inutes%

9% Allo' the test tu#e to cool%

0% Filter the contents of the test tu#e throu$h a

,lter !a!er%

:% Test the o#tained ,ltrate for the !resence ofstarch #y the follo'in$ "ethod%

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