The invention provides processes to make slowly digestible starches from native and commercial starches. Slowly digestible starches are prepared by controlled hydrolysis of gelatinized starch by alpha amylase. The slowly digestible starches have a range of starch digestion rates and fall between normal, untreated commercial and native starch, and commercial resistant starches. The slowly digestible starches provide a range of starch functionalities. These slow digesting starches retain their digestion characteristic after cooling, and can used in a range of processed food products to modulate the rapid glucose release typical of many processed starchy foods. Edible products incorporating slowly digestible starch will exhibit lower glycemic index and increase satiety. The invention provides solid and liquid food, nutritional, and drug preparations containing the slowly digestible starch. The invention further provided edible products for extended energy release for example, for use in sports drinks and snack bars. The slowly digestible starches can also be employed as functional food grade additives to provided beneficial rheological or other properties to edible compositions.