In the manufacture of ketchup acetic-acid extracts of the spices
are sometimes used instead of the whole spices, on account of their
supposed antiseptic properties as well as their greater strength and
convenience in handling. One minim of the standard acetic-acid extracts
is equal in strength to 1 grain of the whole spices. The acid extracts
obtained included allspice, celery, cloves, coriander, garlic, and
black pepper.
In the tests 0.1, 0.2, 0.3, 0.4, 0.5, and 1 cc, respectively, of the
extract was added to 10 cc of tomato bouillon. One set was inoculated
with the mold and another set with the yeast. In the case of the mold,
no growth occurred with the allspice and cloves; the celery checked
the growth materially, there being no indication of mold until the
sixth day. Normally a fairly strong growth occurs in twenty-four hours.
In the solution containing 0.3 cc there was only one small colony in
thirteen days, and no further development. In the solution containing
the coriander, the growth in the 0.5 cc solution did not appear for
three days, the 1 cc solution showing no growth. The garlic had
practically the same effect as the coriander, while the black pepper
was stronger, no growth appearing in the solution containing 0.5 cc.
The yeast was slightly stronger in resisting the effect of the
extracts. No growth appeared with the allspice and cloves; 0.5 cc
of the celery and 1 cc of the coriander were required to inhibit
growth, and the garlic and black pepper gave similar results, a weak
development occurring in the solutions containing 1 cc.