Hydroxyl groups are functional groups that consist of a hydrogen atom and an oxygen atom, represented as -OH. They play an important role in organic chemistry as they can participate in chemical reactions as nucleophiles or bases. Hydroxyl groups are present in many organic molecules, including alcohols, carbohydrates, and phenols, among others.
In starch, the hydroxyl groups are present in the glucose monomers that make up the starch molecule. These hydroxyl groups can be modified through chemical or physical processes to change the properties of the starch, leading to the creation of modified starches with different functionalities and uses in food and non-food applications.
In the modification of starch, hydroxyl groups refer to the functional groups (-OH) present in the starch molecule. These hydroxyl groups play a crucial role in determining the properties of the starch, such as its solubility, viscosity, and gelling behavior. Modification of starch can be achieved by introducing, removing or altering the hydroxyl groups in the starch molecule. This can result in modified starches with improved functional properties, such as increased stability in acidic or high-salt environments, improved water resistance or increased viscosity.