For centuries tallow was essential to soap and candle
making. Not until the late 20th century was fat from ruminants
considered as a feed ingredient. Before then, it was much too
rare and valuable. Now there is a surplus of tallow due to
increased demand for ruminant meats, development of a
sophisticated rendering infrastructure and an increased volume
of competing vegetable fats and oils.
In 2004, the US production of edible and inedible tallow was
approximately 2.53 million metric tons (US Census), somewhere
between half and three-quarters the global tallow production.
This is a small fraction compared to the >40 million metric
tons of vegetable fats and oils produced globally. Much of the
tallow still goes to the soap and chemical industries to
produce household items, but now there is a plentiful supply
for use in animal feeds. This surplus may be why, in less than
a half-century, tallow has gone from a rare and prized
ingredient to one that is reviled by some as a low-quality,
inferior commodity. So much so, its critics consider tallow
nutritionally unfit for dogs or cats.
Tallow is derived from rendering (melting) the fat away from
trimmings of meat, offal and bone from beef, sheep and pork. Most of the animal fat sold as tallow comes from federally inspected animals and facilities and has a regulated quality and composition. This is something many other fats and
oils can't claim. By definition, tallow is animal fat with a
"titer" of >40°C. This means that upon cooling a melted fat
sample, the temperature at which it re-solidifies is 40°C or
greater. Thus, tallow is a solid or semi-solid at room
temperature.
Most of the animal fat sold as tallow comes from federally inspected animals and facilities and has a regulated quality and composition. Although other animal fats can be found in tallow, it is,
practically speaking, derived from beef because this is a
dominant meat in North America and Europe, and because of the
saturated nature of its fatty acids (saturated fats are solid
at higher temperatures; i.e., 40°C).
Tallow, like other fats, imparts texture and flavor to
foods, is utilized efficiently as an energy source, aids
vitamin absorption and can even modify intestinal passage of
food. Contrary to some myths, digestibility of tallow is high
(apparent fat digestibility of 97% or better) and comparable to
other fat sources like chicken fat and lard. Fat, in and of
itself, will increase palatability of a diet up to a certain
point in cats and without limit in dogs. Even so, among the
different fat sources, beef tallow is well known for being one
of the more palatable. Mutton or lamb tallow is not quite as
palatable, possibly due to the aroma. Animal fat from tallow
has even been shown to benefit "olfactory acuity scores"
(Altom, et al., 2003), which may translate to beneficial
effects during hunting.
For many, the "harder" fats like tallow carry a poor
nutritional connotation due to the negative association of
saturated and "trans" fats with transport lipoproteins,
cholesterol and coronary heart disease. This is really a human
nutritional issue, as coronary heart disease is not a prevalent
health concern for dogs or cats. There is a preponderance of
data that supports a greater consumption of poly-unsaturated
fats like the essential fatty acid linoleic acid (LA) and the
omega-3 fatty acids like linolenic (ALA), eicosapentaenoic
(EPA) and docosahexaenoic (DHA) acid by dogs and cats for the
management of inflammatory diseases and neurological
development.
Unfortunately, these are either in very short supply or void
in tallow. The fatty acids in beef tallow are about 50%
saturated, with a small amount of LA (3.0%) and ALA (0.6%) and
none of the longer chain omega-3s (EPA or DHA). Mutton tallow
has a similar level of saturation (47%), but with a slightly
higher level of LA (5.5%) and ALA (2.3%). Since beef tallow is
considered a "saturated" fat and is a common fat source
encountered by dogs and cats, it often serves as the baseline
or "control" treatment in fatty acid research. On the positive
side, tallow is more shelf stable than less saturated fats and
requires less antioxidant preservatives to achieve shelf life
goals. Tallow also contains a small level of conjugated
linoleic acid that is now showing promise as a potent natural
element in the fight against cancer.
Many petfood companies, especially the "value" and mid-range
grocery brands, continue to use tallow, identified on their
labels as either beef tallow or animal fat. This is most likely
due to cost considerations, as tallow is economically priced
relative to other common fat sources. While tallow suffers from
a negative image, due to its composition of saturated fatty
acids, lack of essential and beneficial poly-unsaturated fatty
acids and negative press associated with BSE and beef or beef
byproductsit is equal to, or better than, many competing fats
or oils in terms of digestibility, palatability, cost and shelf
stability.
In general, tallow is a good "platform" to provide energy
and flavor, but a balanced diet may require a pinch of a
complementary oil enriched with LA and (or) omega-3 fatty
acids.