Food Lipids: Chemistry, Nutrition, and Biotechnology

Figure 6 Structure of sorbestrin (cyclic form).
Trehalose octaacetate has been used to interesterify FAME catalyzed by Na
metal to produce highly substituted trehalose polyester with properties similar to
those of sucrose polyester (13). Therefore, trehalose polyester can be used as a zerocalorie
fat substitute in place of sucrose polyester. The only problem is cost effectiveness,
since sucrose is a cheaper substrate than trehalose. The structure of trehalose
polyester is depicted in Figure 7.
4. Raffinose Polyester
Raffinose, like sucrose, is a heterogeneous nonreducing sugar. Raffinose is made of
galactose–glucose–fructose units. It has 11 hydroxyl groups that can be esterified
with fatty acids. It is well established that as the degree of substitution of a carbohydrate
with fatty acids increases, the susceptibility to hydrolysis and absorption
decreases. Based on this fact, raffinose undecaacetate was used to interesterify FAME
to produce raffinose polyester containing 10–11 fatty acids in 99% yield. The reaction
was catalyzed by Na metal at 110�C for 2–3 hours (10). The product had
consistency in the range of salad oils and sucrose polyesters, with some raffinose
polyesters being slightly more viscous than sucrose polyesters and salad oils depending
on the fatty acid composition and degree of substitution. The structure of
raffinose polyester is shown in Figure 8.
Figure 7 Structure of trehalose polyester.
Copyright 2002 by Marcel Dekker, Inc. All Rights Reserved.