Starch turns to maltose when digested. If you want to test for both starch and maltose you will need to add Benedict's reagent to get a positive result for both. You may find the information on this website helpful for more information: http://flashcarddb.com/cardset/76799-starch-digestion-flashcards Based on your question, you could assume that the positive tests following incubation indicate that the starch was somewhat converted to maltose allowing for a positive result for both. However, if you have used Benedict's reagent, you would get a positive for both even if all of the starch had been digested.
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All reducing sugars gives +ve result to benedict test while they give -ve result for the iodine and fermentation test this is because in iodine and fermentation test we are taking a polysaccharide carbohydrate which are non- reducing sugars while all the monosaccharides are reducing sugars.
Sugars with hemiacetal group will give positive test while those with acetal such as glucose will give a negative test.