Functional, thermal, and molecular properties of ozonated starches

Abstract

Abstract Starch modification by oxidizing agents is often carried out using H2O2 and Sodium Hypochlorite. The use of these chemicals, however, has several drawbacks such as chemical residue left in food, low recovery, high wastewater containing salt, and pollution to the environment. Ozone is a good alternative oxidant having some advantages over the other chemical oxidants in leaving no residues, producing no waste and being a powerful oxidant and generally recognized as safe (GRAS). Starch modification using ozone results in the formation of new carbonyl groups and carboxyl groups. These functional groups are derived from the oxidation of the hydroxyl group present in starch. Therefore the extent of oxidation to the starch is indicated by the amount of carbonyl and carboxyl groups formed, especially in the hydroxyl group in positions C-2, C-3, and C-6. The change in functional group of hydroxyl to carbonyl and carboxyl has an implication to the change of crystallinity, morphological, pasting, functional and thermal properties of native starch granules. Starch modification is also highly dependent on the types of starch. The fact that ozonation of starch gains considerable interest, it is thus very important to elaborate on the different effects of ozone oxidation on starch properties. This information would be useful for the development of new ozone-modified starch materials hence more choices for food industrial applications.