3.3.2 Water holding capacity
Water holding capacity (WHC) is a property
of dietary fiber which is important from a
technological point of view that it can be applied in
food products as a new ingredient for a low-calorie
healthy diet and for modifying the physical properties
and texture of food products [21]. Dietary fiber
binds with water by the interaction between polar
and hydrophobic interactions [26]. WHC of FDF
was 9.8 g/g fiber which was greater than the value
obtained from DDF, 4.9 g/g fiber (Table 1). FDF
seemed to have ability to trap water inside the fiber
matrix more than DDF. Chaplin (2003) reported
that dietary fiber bind with water by the interaction
between polar and hydrophobic interactions. These
reactions varied with the flexibility of the fiber
surface [26]. The environment condition such as
pH, ionic strength, temperature, nature of the ions can also make the hydration properties of dietary
fiber change [27]. Mechanical properties such as
shear force and drying process can also influence
the surface of dietary fiber as the kinetics of water
uptake, the decrease of water retention and water
absorption capacity [27]. In this study the content
of IDF of DDF was lower when compared with that
of FDF. Hence, it resulted in a lower WHC value
of DDF