A chemical test for starch involves adding an iodine solution (yellow/brown) and observing the color change. Iodine becomes blue-black in the presence of starch. This iodine solution test can identify starch from glucose (and other carbs). Glucose is the only carbohydrate that changes color when exposed to iodine; all others remain yellow or brown. Starch is found in many plants, especially grains like wheat, corn, and potatoes. Starchy vegetables include peas, carrots, sweet potatoes, and yams. Even fruit contains some starch! The skin of most fruits contains small amounts of starch which help retain the shape of the fruit before it is harvested. Once harvested, the starch converts to sugar which fuels the growth of the fruit. Damaged or cut fruit will eventually spoil due to the conversion of its starch into sugar too fast. Most fruits are high in fructose which can cause tooth decay if eaten in large quantities. When you eat foods with starch, the body converts them into sugars which are then absorbed into blood cells where they are used as energy. This process requires a lot of energy so after eating foods with starch, your body will need to work hard to convert these sugars back into starch so they can be used later. Foods with a lot of starch also give you lots of energy for a short time because there's so much of it that your body doesn't have to work very hard to break it down.