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Food Lipids: Chemistry, Nutrition, and Biotechnology

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Another approach to mimicking the functional properties of cocoa butter is<br />

through the use of special fractions of a combination of domestic <strong>and</strong> tropical (nonlauric)<br />

fats that have been selectively hydrogenated. The fats often used include soy,<br />

canola, cotton, <strong>and</strong> palm. The manufacture of chocolate-flavored coatings using these<br />

final blends of fat in place of cocoa butter is well known, <strong>and</strong> these coatings have<br />

a real place in the market in certain applications where rate of melting of the fat in<br />

the mouth <strong>and</strong> ultimate flavor release are not key factors in consumer acceptance of<br />

the product. They do have the drawback, however, of some amount of ‘‘waxiness’’<br />

that can be detected in the mouth, since a fraction of their triglycerides does melt<br />

above body temperature. This effect is minimized when chocolate-flavored coatings<br />

made with these cocoa butter replacers are used on baked goods, where the crumb<br />

structure of the substrate aids in the mastication of the coating <strong>and</strong> helps minimize<br />

the perception of waxiness in the mouth.<br />

The most popular approach for the formulation of chocolate-flavored coatings<br />

is the use of cocoa butter substitutes (CBSs), based on lauric fats. These coatings<br />

are widely used in both the chocolate/confectionery <strong>and</strong> baking industries. The principal<br />

base fats used in their manufacture are palm kernel oil <strong>and</strong> coconut oil, with<br />

the former being the more widely used. The specific fatty acid composition of these<br />

fats <strong>and</strong> their various fractions after processing is shown in Table 6. These fats<br />

contain triglycerides that are high in the esters of lauric <strong>and</strong> myristic acid. Triglycerides<br />

of these compositions form crystals that are relatively small <strong>and</strong> uniform, <strong>and</strong><br />

have a sharp melting point around body temperature. The set point of these fats is<br />

also, typically, very sharp, <strong>and</strong> they provide a coating base that has significant solids<br />

at room temperature. With their high levels of lauric <strong>and</strong> myristic acids, however, it<br />

is obvious that a significant percentage of these fatty acids will occur on all three of<br />

the available positions, in a r<strong>and</strong>om manner. Because these triglycerides are of vastly<br />

different compositions <strong>and</strong> are nonstructured, coatings based on them are not compatible<br />

with cocoa butter; hence the ultimate coatings can tolerate only minimal<br />

levels of cocoa butter containing ingredients, such as cocoa powder, <strong>and</strong> the flavor<br />

impact of these coatings is usually degraded by these restrictions. They do have<br />

better melting properties than the cocoa butter replacers discussed above, however,<br />

with the noticeable absence of any lingering waxy mouthfeel.<br />

With the production of the first crop of laurate canola, we were faced with a<br />

totally new type of triglyceride: one that was high in lauric acid esters, though not<br />

Table 6 Fatty Acid Composition (wt %) of Processed Palm Kernel <strong>and</strong> Coconut Oils<br />

Oil C12 C14 C16 C18 C18:1 C18:2<br />

Palm kernel oil 47.0 17.0 8.5 3.0 11.0 2.0<br />

Hydrogenated at 35�C 47.0 17.0 8.5 13.0 7.0 —<br />

Hydrogenated at 40�C 47.0 17.0 8.5 19.0 1.0 —<br />

Fractionated 55.0 21.0 8.5 2.0 7.0 1.0<br />

Hydro/fractionated 55.0 21.0 8.5 10.0 — —<br />

Interesterified/hydrogenated 47.0 17.0 8.5 19.0 1.0 —<br />

Coconut oil 47.5 17.5 8.5 2.5 7.0 1.5<br />

Hydrogenated 47.5 17.5 8.5 10.0 1.0 —<br />

Copyright 2002 by Marcel Dekker, Inc. All Rights Reserved.

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