Starch
Starch is a type of sugar that plants make to store energy in foods like rice and potatoes.
A jar holds a stack of dried pasta — dozens of pieces packed tightly inside. Plants store starch the same way: small sugar units linked in long chains, packed into seeds or roots. Each piece of pasta is like one sugar unit. The jar holds them all until the plant needs energy.
Explaining starch by grade level
Plants make starch to save energy. Rice and potatoes hold a lot of starch. You can find hidden starch with iodine drops. The drops turn dark blue on starchy foods.
Projects that explore starch
Plants store energy as starch in foods like rice and potatoes. When iodine solution touches starch, it turns dark brown or blue-black — making it a simple detector for hidden starch in everyday kitchen foods. That color change reveals which samples, like raw potato and flour, hold stored plant energy, and which, like butter and meat, hold none at all.
Starch is a type of sugar that plants make to store energy, and apples hold some of that stored energy as starch. As apples ripen in warmer conditions, that starch breaks down — along with malic acid, the sharp flavor in a tart apple. By testing starch levels with iodine spray at storage temperatures of 4, 21, and 32 degrees C, you can track how both compounds decrease as temperature rises and storage time lengthens.