f less
importance now than in years gone by; first, because most coffees now
come to market more perfectly graded and cleaned than formerly; and
second, because the whole-bean appearance of the coffee has become of
less account, as wholesale grinding operations have increased.
Nevertheless, many plants consider it highly important to have a
separator for grading the coffee closely as regards the size of the
beans--and particularly for the separation of round beans, or
"peaberry"--as well as milling machinery for making the coffee as clean
as possible before it is roasted. One green coffee operation that has
lost none of its old-time importance, but on the contrary is more needed
as the plants increase in size, is the mixing of different varieties of
coffee--in proportions that have been decided on by sample tests--so as
to get a uniform blend.

The mixer does not blend the various coffees any more surely than a good
roaster cylinder will do it, but treats batches of much larger size.
This means saving a great amount of labor that would be necessary for
putting the desired quantity of component coffees into each individual
roaster.

A proper installation of green coffee machinery requires various bins of
ample capacity, and bucket elevators by which the coffee can be sent
without manual labor from one operation to another. In modern plants,
all the bins and elevators are constructed of metal. The separator, with
its bins and elevator, may be installed independently of the rest of the
plant, the graded coffee being all bagged up again and treated as new
raw stock--some of it to be held for later use, or perhaps sold again
unroasted. The milling machine and the mixer, however, are usually so
placed and connected that the coffee can be sent from one to the other,
and to the roaster feed hoppers, without any manual labor.

When the roaster sells his product in package form ready for the
consumer, he will have a packaging department in which are grinding,
weighing, labeling, and packing machines and equipment. In some of the
more progressive plants, particularly in the United States, all the
packing units are incorporated in one machine, so that the different
steps in the work are carried on automatically and in one continuous
operation.

[Illustration: GREEN-COFFEE-MIXER CONNECTIONS

To operate at full capacity, without using the story above as well as
below the mixer, requires a bucket elevator and three bins, each ho