On food and cooking the science and lore of the kitchen ( PDFDrive ) 1506
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Cocoabutter 60 35 2
Vegetableshortening 31 51 14
Cottonseedoil 26 18 50
Stickmargarine 19 59 18
Tubmargarine 17 47 31
Peanutoil 17 46 32
Soybeanoil 14 23 58
Oliveoil 13 74 8
Cornoil 13 24 59
Sunflowerseedoil 13 24 59
Grapeseedoil 11 16 68
Canolaoil 7 55 33
Saffloweroil 9 12 75
Walnutoil 9 16 70
Hydrogenation:AlteringFatSaturationFor
morethanacenturynow,manufacturershave
been making solid, fat-like shortenings and
margarines from liquid seed oils to obtain
boththedesiredtextureandimprovedkeeping
qualities. There are several ways to do this,
the simplest and most common being to
saturate the unsaturated fatty acids
artificially. This process is called
hydrogenation, because it adds hydrogen
atoms to the unsaturated chains. A small
amount of nickel is added to the oil as a
catalyst, and the mixture is then exposed to
hydrogen gas at high temperature and
pressure. After the fat has absorbed the
desired amount of hydrogen, the nickel is
filteredout.
Trans Fatty Acids It turns out that the
hydrogenation process straightens a certain
proportion of the kinks in unsaturated fatty
acids not by adding hydrogen atoms to them,
butbyrearrangingthedoublebond,twistingit
so that its bend is less extreme. These
molecules remain chemically unsaturated —
thedoublebondbetweentwocarbonsremains
