Food Lipids: Chemistry, Nutrition, and Biotechnology

Table 2 Triacylglycerol Makeup for Olive Oil–Tristearin Blends Before
and After Interesterification
Species a
SSS
SSU
UUS
UUU
75–25% (w/w)
Initial Randomized
25.1
3.4
23.4
46.9
a
S, saturated; U, unsaturated.
Source: Ref. 53.
Olive oil–tristearin in blend
4.4
24.1
44.3
27.2
80–20% (w/w)
Initial Randomized
20.1
3.6
25
50
2.8
19.2
44.2
33.9
idence time determined by the coil length and the flow rate of the oil. The catalyst
is then neutralized with water, separated from the oil by centrifugation, and dried
[14].
Rozenaal [11] mentioned a continuous interesterification process in which a
solution of sodium hydroxide and glycerol in water was used as precatalyst. Heated
oil was mixed with the catalyst solution and subsequently spray-dried in a vacuum
drier to obtain a fine dispersion and to remove the water. The reaction could be
carried out in a coil reactor at 130�C. With this setup, the reaction took only a few
minutes.
D. Regioselectivity in Interesterification
Elegant work by Konishi et al. [45] demonstrated that chemical interesterification
can be regioselective. Sodium methoxide–catalyzed ester interchange between soybean
oil and methyl stearate in hexane, at 30�C, revealed that fatty acid interchange
at sn-1,3 positions progressed 1.7 times faster than at the sn-2 position after 24 hours
of reaction.
Figure 7 Batch random interesterification reaction vessel. (Adapted from Refs. 3, 14, and
28.)
Copyright 2002 by Marcel Dekker, Inc. All Rights Reserved.