Increasing the viscosity at ambient temperature is a unique
characteristic of PG starches which makes them different from
their native counterparts. Addition of acetic acid significantly
reduced the apparent cold water viscosity of the samples (Table 3)
from 1392 to 1279 mPa s for PGWS (8.11% reduction) and from
1132 to 864 mPa s for PGCS (23.67% reduction). Similar results
were reported for native cassava starch and instant maize and
wheat starches in the presence of various levels of L-ascorbic acid
(Majzoobi et al., 2015; Sriburi, Hill, & Mitchell, 1999). These
changes can be related to the formation of smaller starch molecules in the presence of acetic acid with less swelling and water
absorption capacity (see Table 2). It was noted that the cold water
viscosity of the PGWS was higher than that of PGCS at various concentrations of acetic acid. This can be attributed to the higher
water absorption of PGWS (see Table 2) and possibly its larger
molecular size