There is a desirable range of dough consistency to ensure ease of
donut preparation (Shih et al., 2001). As shown in Table 2, wheat
dough had a consistency of about 2.37 N, while that of soy dough
was at least six times higher (13.64e18.71 N) (p < 0.05). The results
of our data concur with the yackwa (Korean traditional fried
cookies) study by Lee and Brennad (2005) which reported that the
15% addition of soy protein isolate (SPI) increased the dough consistency
from 1.7 to 2.6 kg-force. The addition of HPMC also
increased the dough consistency. However, the method of addition
of HPMC seems to work differently. SH dough (18.71 N) had the
highest dough consistency, following by S dough (13.64 N) and SHC
(11.57 N). Generally, dough consistency is closely related to the oil
uptake of the fried products (Lee & Brennad, 2005; Shih et al.,
2001). That is, increased dough consistency decreased oil uptake
during frying. Particularly, ingredients with a high water holding
capacity resulted in high dough consistency and low oil uptake.
Consistent with the findings of previous studies, we found strong
correlations between dough consistency and donut oil uptake
(r ¼ 0.877), and dough consistency and dough moisture
(r ¼ 0.965).