Tubers were washed thoroughly,
shredded using a food processor, and further macerated in a
blender with tap water (1:1, w/v) for 2 min at medium speed, and
filtered through a cheese cloth. The residue was resuspended in
tap water (1:0.5, w/v) and macerated in a blender for 2 min. This
step was repeated once more, and the filtrate was mixed and
passed through a 250-mesh sieve. Starch in the filtrate was allowed
to settle for 2-3 hr at room temperature (27–30°C). The supernatant
was decanted and discarded; the starch was resuspended in
water and filtered through a 250-mesh sieve and kept in the refrigerator
(≈7°C) to settle. The last step was repeated once without
the sieving step. The starch sediment was dried in a convection
oven at 50°C overnight, cooled to room temperature, and equilibrated
for 4 hr before samples were packed and sealed in polyethylene
bags for shipment to Hong Kong.