Starch varies nearly as much in source as it does in functionality. No matter the origin of the starch, it can be modified to fit a variety of applications. Physical characteristics differ from one type to another, ranging from grainy to smooth, heavy-bodied to light, opaque to translucent, and soft to firm gelled. Starch can be made to withstand freeze/thaw cycling, heat, mechanical shearing, and an acidic environment. Ingredient suppliers who offer technical assistance are in the best position to capitalize on the needs of product developers, who often are left with the difficult task of customizing formulas that meet their customers' rigorous demands.
Although carbohydrate chemistry can be rather complex, stated simply, amylose is a strong film-former with firm gelling properties, while amylopectin forms weak films and soft gels or is non-gelling. Starch varies in amylose and amylopectin, depending on its ingredient source. Dent corn may only contain 25% amylose, while high-amylose corn may have as much as 55% to 70% or more. Waxy maize, on the other hand, has less than 1% amylose content.