Effects of ultra-high pressure on the morphological and physicochemical properties of lily starch

In this study, starch extracted from lily bulbs were modified using an ultra-high pressure (UHP) treatment at six different pressure levels (100, 200, 300, 400, 500, and 600 MPa). The effects of UHP treatment on the physicochemical and morphological properties of lily starch were investigated. The morphological observation revealed that UHP treatment led to particle expansion and aggregation. Compared with the native and lily starch treated at 100-500 MPa, the lily starch treated at 600 MPa exhibited almost completely disrupted morphology and a larger particle size, indicating nearly complete gelatinization of the starch. The relative crystallinity of the UHP-treated starch remarkably reduced. Gelatinization temperatures via differential scanning calorimetry decreased with increasing pressure. The rapid viscoanalyzer results revealed that the lily starch treated with UHP at 600 MPa showed low values of peak viscosity, trough viscosity, breakdown, final viscosity, and setback. These results indicated that UHP was an effective physical modification method for lily starch, UHP treatment (600 MPa, 30 min) caused nearly complete gelatinization of lily starch, and lily starch modified using UHP might expand the application of lily in the food field.