Pellet

The Pelleting Process
For many years, pelleting was considered an art, a process involving imprecise measurement,
uncertain results, and that undefinable quality of feel. This so-called “art” of pelleting came
about in an environment lacking the understanding of the effects occurring when the differing
characteristics of feed ingredients are subjected to the pelleting processes of heat,moisture, and
pressure. No excuse, however, exists today for the uninformed pellet mill operator.
The science of grain processing has now reached a point that, by knowing the characteristics of
the feed (moisture, content, fiber, etc.) and using machinery with accurate measurements, the
guesswork has been removed from pelleting. As a result, much more is required of the pellet
mill operator in theway of knowledge and ability. The skill of the pellet mill operator, through
his ability or mistakes, influences plant profitability.
Pellet mill operators have a vitally important role in the manufacture of animal feed. They
should recognize this responsibility and the great contribution they make to an efficient feed
plant.
INTRODUCTION TO PELLETING
The Purpose of Pelleting
Pelletedfeeds have been defined as “agglomerated feeds formed by extruding individual
ingredients or mixtures by compacting and forcing through die openings by any mechanical
process”. Basically, the purpose of pelleting is to take a finely divided, sometimes dusty,
unpalatable and difficult-to-handle feed material and, by using heat, moisture and pressure,
form it into larger particles. These largerparticles are easier to handle, more palatable and
usually result in improved feeding results when compared to the unpelleted feed.
Pellets are generally formed with diameters from 10/64” to 48/64” and will be somewhat longer
than the diameter. A small part of the production of large pellets, 32/64” and above in diameter,
is produced in other than cylindrical shapes; they may be triangular, squareor oval and, in some
cases, may exceed the maximum dimension indicated above. The largest diameter usually found
is rarely greater than 1-1/4” to 1-3/8”. In most cases where particle sizes smaller than 10/64” are
desired, it has been found to be more satisfactory from the standpoint of economics to produce a
10/64” or 12/64” pellet and reduce it into the desired particle size by means ofcrumbling.
Almost all livestock feeders agree that animals make better gains on pelleted feed than a meal
ration. The most logical reasons are that (a) the heat generated in conditioning and pelleting
make the feedstuffs more digestible by breaking down the starches, (b) the pellet simply puts the
feed in a concentrated form, and (c) pelleting minimizes waste during the eating process. Whenpelleted feed is fed, each animal receives a well-balanced diet by preventing the animal from
picking and choosing between ingredients. Tests have shown that most animals, if given the
choice between the same feed in pellet or mash form will prefer the pellets.
By combining moisture, heat and pressure on feed ingredients, a degree of gelatinization is
produced which allows animals and poultry tobetter utilize the nutrients in these ingredients.
California Pellet Mill Co.
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Feed conversion will be improved. These advantages are particularly noticeable in the broiler
industry.
The feeding merits of pelleted feeds over the mash form have been repeatedly demonstrated in
the feeding of swine. One state college reported the results of an eight week swine feeding test in
which pelletedfeed performance was compared against the same feed in mash form. This test
gave the following results:
All animals, on the average, consumed the same amount of feed (5.06 lb. per day of pellets vs.
5.02 lb. per day of mash), yet the pellet fed pigs gained a quarter of a pound per day more weight
than did the mash fed animals (1.76 lb. vs. 1.54 lb. of gain per day). Since the pellet fed hogs...