Food Lipids: Chemistry, Nutrition, and Biotechnology

as high as coconut or palm kernel oils, but one in which all the C12:0 and C14:0
occurred on the sn-1 and sn-3 positions, and the sn-2 position was occupied solely
by C18:x fatty acids, where x = 1, 2, and/or 3. Selective hydrogenation of this oil,
then, would allow us to closely control the melting properties of the resulting triglyceride
and to manipulate the solids profile of the final fat system. When these
new fats were utilized in typical formulated food systems, it was noted that the
systems offered flavor release that was far superior to that obtainable with the corresponding
tropical laurics. Although this statement is based on anecdotal data, a
great deal of effort is under way to quantify the flavor release properties of these
new structured fats versus the random lauric fats typically used. It could be immediately
demonstrated, however, that this new source of a lauric fat used in confectionery
was highly compatible with cocoa butter—a trait not encountered with the
tropical laurics—hence could be used with cocoa butter sources that lead to higher
flavor in the finished product. These obvious differences in how the genetically
engineered laurate canola performed with respect to existing laurics were explored
at some length and are discussed later (Sec. V.B.2).
3. Investigations Driven by Purported Health Benefits to the Consumer
a. Low Saturates. Consumer concern over saturates has driven food marketers
to look for ways to differentiate their products on the basis of saturated fat content.
Food labeling regulations recently published by the U.S. Food and Drug Administration
(FDA) allow products containing less than 3.4% total saturates to be labeled
as containing no saturated fat. With the size of the current salad and frying oil
markets as a target, the potential justified examining and developing a technical
strategy to address this opportunity. Over 45% of the vegetable oil consumed in the
United States is used in salad and cooking oils. More than 6.5 billion pounds of
vegetable oils (valued at $1.7 billion, wholesale) was used in this segment in 1992.
The U.S. salad and cooking oil market is characterized by slow but steady growth,
driven largely by population increases. The principal oils used in the production of
retail salad and cooking oils in the United States are soybean, canola, corn, sunflower,
cottonseed, and peanut oils (see Fig. 7).
Saturate levels in liquid oils have become a significant issue for consumers
because of reports linking saturates to coronary heart disease. Saturates have been
shown to lower the levels of high density lipoprotein (HDL) cholesterol. The FDA
now requires that food labels list saturate levels. These concerns have already had a
major effect of the U.S. salad and cooking oil segment, driving canola oil (with
lower saturates than other oils) consumption from 263 million lb in 1987 to over 1.2
billion pounds in 1993. Consumption of saturated tropical fats decreased by 17.8%
over the same period. Consumer concern over saturates is projected to continue to
play a key role in this market segment, and food companies will continue to search
for products that address this concern.
Since canola oil contains the lowest level of saturates of any of the commonly
used food oils, it seemed a natural base from which to launch a variety of approaches
that would lead, ultimately, to the desired product. As it turned out, the research was
not trivial. A combination of mutagenesis and the use of two different genes led to
a canola oil having a saturates level between 4.0% and 4.5%, but with questionable
agronomic performance. The presence of relatively high levles of polyunsaturated
C18 fatty acids also contributed negative performance characteristics when the oil
Copyright 2002 by Marcel Dekker, Inc. All Rights Reserved.