Oil extracts of the spices were tested in the same manner as the water
infusions and the acetic-acid extracts. The oils were so strong that
in order to handle them easily they were mixed with equal volumes of
alcohol, except that the mace, which was in the form of a paste,
was mixed with two-thirds its volume of alcohol. To 10 cc of tomato
bouillon were added 0.1, 0.2, 0.3, 0.4, and 0.5 cc, respectively, of
the oils of cinnamon, cloves, mace, mustard, and black pepper.
In the case of the mold, there was no development in the solutions
containing cinnamon, cloves, and mustard; in those containing mace
and black pepper the development was slower than the normal, that in
the black pepper being more pronounced. On the yeast the effect was
similar, no development occurring in the cinnamon, cloves, and mustard,
and a retarded development taking place in the mace and black pepper,
that in the black pepper being the more pronounced.
The experiments show that some of the spices, notably allspice,
cinnamon, and cloves have decided antiseptic value, but that the
peppers are not as valuable as is generally supposed.
The oil extracts have been advocated for use in ketchup instead of the
whole spices, but in quantities which would be useful antiseptically
their use would be objectionable, for when present in approximately
the same proportions as are the whole-spice infusions, the flavor
is too strong and masks the more delicate flavor of the tomato. The
acetic-acid extracts are more effective than are the water infusions,
and they are not objectionable in the ketchup.