TOTAL ASH DETERMINATION IN SPICES 1 
By A. L. Mehring 
Meat Inspection Division , Bureau of Animal Industry , United States Department 
of Agriciriture 
The chemical determination most 
widely used by chemists in passing 
upon the quality of finely ground spices 
is that of total ash. This is best ob¬ 
tained by igniting one or two grams of 
the material, contained in a porcelain 
or platinum crucible, in a muffle fur¬ 
nace at the lowest temperature that 
will give a carbon-free residue. Heat¬ 
ing for one hour at approximately 
700° C. is usually sufficient. Red 
peppers require a little higher tem¬ 
perature than other spices to obtain 
the same result. Care must be exer¬ 
cised not to use a higher temperature 
than a dull red heat, or decomposition 
of carbonates in the ash will result. 
Water-soluble and hydrochloric-acid- 
insoluble ash are determined usually 
only when the total ash or microscopic 
examination arouses suspicions of im¬ 
purity or adulteration. If the total ash 
is low for the spice under consideration 
and the water-soluble ash very low* 
the spice has probably been extracted. 
If the reverse is true of the total and 
acid-insoluble ash the spice contains 
extraneous mineral matter. 
The color and appearance of the ash 
often tell something about the spice 
from which it was derived. Pure red 
peppers give a light gi eenish-blue ash, 
which is due to the presence of copper. 
American saffron or safflower has a 
red-brown ash; Spanish saffron yields 
a white or very pale gray ash; cinna¬ 
mon ash is white or nearly so, and that 
of cassia is brown or brownish gray; 
clove ash is dark green, while most 
other kinds are white or gray. If spice 
ash is rubbed between the fingers the 
presence of foreign mineral matter in 
the original will be evidenced by a 
gritty feeling. 
In spite of the simplicity of a total ash 
determination, the figures reported by 
different investigators vary consider¬ 
ably. A survey of the literature re¬ 
veals the following partial list of figures 
as the average percentage of total ash 
in pure ginger: 4.39, 5.36, 5.55, 6.01, 
3.80, 5.27, 3.62, 6.78, 3.66, 5.88, and 
4.46. The first four are averages of 
more than 50 determinations each. 
Similar variations occur in results re¬ 
ported for othei spices. This is chiefly 
due to variation in the spice itself and 
to a less extent to the peisonal equation. 
Richardson (89) 2 gives the total ash 
in Acheen black pepper as 8.99 per cent 
and that of Singapore black pepper as 
5.41 per cent. These peppers are ob¬ 
tained from the same botanical species 
and the difference is largely due to varia¬ 
tions in the circumstances surrounding 
theii production, such as soil, climate, 
and handling. 
Almost as large differences occur in 
spices from the same source from year 
to year as in those from different 
sources. This is due to differences 
in climatic conditions and has been 
well shown by Sindall (11). Table I 
has been prepared from some of his 
figures, each of which is the average of 
a large number of determinations upon 
pure cinnamon, imported from the 
same sources in successive years. 
Table I .—Per cent of ash in cinnamon 
1908 
1909 
i 
! 1910 
1911 
China cinnamon_ 
4.79 
3. 77 
3. 84 
3. 27 
Batavia cinnamon_ 
4.68 
3.79 
3. 78 
4. 32 
In 1908 the average ash content of all 
samples from China was higher and in 
1911 lower than that of Batavia sam¬ 
ples in any year. The averages of the 
best figures available for four different 
varieties of cinnamon come between 4 
and 4.15 per cent. 
This variation is further shown by 
the percentages following which are the 
averages presented by numerous in¬ 
vestigators for different varieties of 
black pepper. 
1 Received for publication May 22, 1924—issued February, 1925. 
2 Reference is made by number (italic) to “ Bibliography,” pp. 572-574. Citations in the bibliography 
which are not referred to in the text were used in the preparation of the tables. 
Vol. XXIX, No. 11 
Dec. 1, 1924 
Key No. A —87 
Journa lof Agricultural Research, 
Washington, D. C. 
( 569 ) 
