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Why doesn't starch give a positive Benedicts test?

Why doesn't starch give a positive Benedicts test?
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A starch molecule is made up of 100's of glucose monomers. And each glucose monomer in a starch is linked with another glucose monomer by alpha -1,4 linkage due to which a starch molecule does not have a free aldehyde group which is opresent in a free glucose molecule. At its end it may have a free aldehyde group, but is too small in amount to show the reaction in comparision to a huge glucose monomer. As Benedict's Test is a test to determine presence or absence of a aldehydic group; a starch molecule can not show a positive glucose test. But if a starch molecuse is hydrolysed with help of an acid or amylase enzyme it will certainly show hte positive glucose test

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