Souring is detected and located by means of a pointed metal instrument
known as a “ham trier,” which resembles a long, slightly flattened ice
pick. The trier is thrust into the ham at different points along the
bone, rapidly withdrawn, and the odor which clings to the metal noted.
The trained inspector works very rapidly, and is able to detect even
the slightest sour or off odor which might be imperceptible to one not
trained to the work. At the end of the cure all hams are tested with
the trier under the supervision of Government meat inspectors.
Hams are also given what is called the “30-day inspection” by plant
inspectors during the process of curing. An average ham weighing
from 14 to 16 pounds requires about 60 days to cure, and at the end
of 30 days a certain number of hams in each run are usually tested
to see how the cure is progressing. If no sour hams are discovered
at this inspection the packer knows that the cure is progressing
satisfactorily, and moreover he feels sure that his hams will finish
satisfactorily, for experience has taught him that souring develops
within the first four weeks of the curing period, and if his hams are
sweet at the end of this time, he can feel practically sure that no
sours will develop later on.