Starches can be chemically altered (i. e. , modi ed) by various means in order to obtain modi ed starches that have desired properties. Various modi cations include acid treatment, enzyme treatment, cross-bonding, substitution, oxidation, and heat. Acid modi ed starch (thin boiling starch) is produced by holding starch granules below their gelatinization temperature in an acidic medium. The acid hydrolyzes glycosidic linkages in starch without breaking up any granules. The product is then dried and used as a powder. It has applications in candy manufacture because it produces low viscosity uids that are easy-to-handle and can easily be poured into molds, but will set into rm gels upon cooling or aging. Starch gum candies, including gummy bears, are produced using acid modi ed starches. Enzymes can be used instead of acid to hydrolyze starches into thin boiling varieties. Cross-bonded starch (cross-linked starch) is produced by forming covalent links (think bridges) between adjacent starch chains.