The impact of water content
was readily evident in the volume of breads obtained from fine
flour (Fig. 1). The plasticizer effect of the water is crucial when
making gluten-free breads because it contributes to the extensional
properties of the dough during mixing (Marco & Rosell,
2008). It must be stressed that fine particles increase the contact
surface, thus greater amount of water is necessary for hydrating
the raw material and later on for swelling starch granules. This
could be the explanation of the very low specific volume achieved
by breads obtained from fine flour and low water content (70%).
Nevertheless, that deficiency was partially corrected when the
amount of water increased allowing the hydration of the particles
(Table 1). Han, Cho, Kang, and Koh (2012) reported that excessive
water caused overexpansion during baking resulting in large-volume
breads. Nevertheless, too much water led to big holes in the minimised by increasing the water content. The specific volume of
breads made with coarse flour and 90% or 110% of water did not
show significant differences, suggesting that the optimal water
content for this particle size is around 90–110%.
The coarse flour led to breads with lower water retention ability
as indicated by its significantly higher weight loss, which also increased
with higher water content (Table 1). The lower water
retention might be attributed to the lower hydration ability of
the coarse particles compared to the fine ones.