The effect of addition of high-melting monoacylglycerol and candelilla
wax on pea and faba bean protein foam-templated oleogelation
Abstract
Oleogels prepared from hydrocolloids have recently gained a lot of
attention as an alternative for trans and saturated fats. Previously we
have demonstrated that the freeze-dried foams prepared using a mixture
of 5% faba bean or pea protein concentrates with 0.25% xanthan gum at
pH 7 and 9 can hold canola oil 30-40 times their weights (Mohanan, Tang,
Nickerson and Ghosh, 2020). However, the oleogels suffered from high oil
loss, about 30% oil leaked, which negatively affected the rheological
properties of the oleogels. The functionality of the cake baked using
the oleogels was poorer compared to a shortening baked cake. The present
study explored the addition of a small amount of high-melting
monoacylglycerol (MAG) and candelilla wax (CW) on reducing oil loss,
improving rheological properties and baking qualities of pulse
protein-stabilized oleogels. Different concentrations (0.5-3%) of MAG
or CW were dissolved in canola oil at 80 ºC. The hot oil was then added
into the freeze-dried protein-polysaccharide foams (pH 7) and quickly
transferred to a refrigerator. The crystallized additives reinforced the
oleogel network, thereby reducing oil loss while increasing the
firmness, cohesiveness, and storage modulus. When model cakes were baked
with the oleogels, significant improvement in textural properties was
observed with the addition of MAG in the foam-templated oleogels.
However, in comparison with shortening-based cakes, oleogel-based cakes
still showed a negative effect on hardness, chewiness and cohesiveness.