Impact of high pressure on starch properties: a review

Large amounts of different starches are produced worldwide since starch is widely used as a functional component in prepared foods and is one of the most important sources of energy for humans. However, in its native form starch does not have properties suitable for processing due to low thermal stability and high retrogradation. To promote and enhance these and other properties, starch is modified by chemical, physical, or enzymatic processes. Treatments such as high-pressure processing can be used to break/change non-covalent chemical linkages in and between starch molecules in order for starch to have the desired properties. The use of pressure can increase starch swelling and solubility depending on the temperature. Higher pressure levels can disrupt the starch granule morphology, induce the starch gelatinization and the granules birefringence can consequently decrease. Pressure can also alter significantly the thermal properties of starch, as well as its pasting properties, the dynamic oscillation and steady flow behavior of starch, and the amount of resistant/fast/slow digestible starch. The use of pressure can also delay/decrease starch retrogradation and change starch polymorphism from type A or C to type B. However, the change of these properties is always dependent on the pressure level, solvent type and treatment time used, but also from the starch type and origin. This paper revises the effect of high pressure on starch properties in order to improve their quality to obtain the desired properties that can promote human health.