Physically Modified Starch

The demand for starch is never-ending and is increasing at an alarming rate worldwide for its food and nonfood applications. However, native starch has some limitations, such as low gel strength, viscosity, water binding capacity, and thickening properties. This leads the researchers to find various ways of modifying the starch to improve its beneficial qualities and correct the drawbacks of natural starches. The starch modification industry is changing continuously, providing various physical, chemical, and enzymatic methods and sometimes their hybrids. Among these, the physical modification methods possess higher safety, environmental friendliness, and cost-effectiveness without leading to the production of chemical wastes. The physical modification methods can be divided into two categories: thermal and nonthermal. The former category includes heat-moisture treatments, annealing, microwave heating, and osmotic pressure treatment, while the latter includes ultrasonication, ultrahigh-pressure treatments, and pulsed electric fields. This chapter covers recent advancements in thermal and nonthermal physical modification of starch, their principles, procedures, and their effect on starch functionalities.