Wheat starch was dispersed in deionized water by stirring at
25 C for 3 h to produce starch suspensions with a final concentration
of 40% (w/w). Then the samples were frozen at 34 C for
22 h and thawed in water bath at 25 C for 2 h. This freezing/
thawing cycle was repeated for several cycles (3, 7, and 10
respectively) before centrifugation at 2200 g for 20 min. The
starch residues were collected after being freeze-dried with Labconco
FreeZone (Labconco, USA). Control samples were stirred at
25 C for 3 h and then directly centrifuged at the above conditions.