Effect of high pressure on rheological and thermal properties of quinoa and maize starches

- High hydrostatic pressure (HHP) treatment preformed on quinoa and maize starches.
- Effects of HHP up to 600 MPa on rheological and thermal properties of starch analyzed.
- Quinoa starch more susceptible to HHP treatment than maize starch.
- Effects of granular and molecular structures on HHP outcomes discussed.

Quinoa starch has small granules with relatively low gelatinization temperatures and amylose content. High hydrostatic pressure (HHP) is a non-thermal technique for food processing. In this study, effects of HHP up to 600 MPa on physical properties of quinoa starch were studied and compared with those of a normal maize starch. Both starches gelatinized at 500 and 600 MPa. The pressure of 600 MPa completely gelatinized quinoa starch as revealed by thermal analysis. Dynamic rheological analysis showed that HHP improved the gel stability of both starches during cooling. HHP had little effects on amylopectin recrystallization and gel textural properties of starch. Overall, quinoa starch was more susceptible to HHP than maize starch. The effects of HHP on some rheological properties such as frequency dependence were different between these two types of starches. The differences could be attributed to the different composition, granular and chemical structures of starch, and the presence of granule remnants.