of sulphur-containing volatiles are responsible
for the formation of garlic breath. Laasko
et al were among the first to make the distinction
that the composition of sulphur- containing volatiles
was different when garlic-borne volatiles are
generated in the mouth versus the garlic odour
compounds present in garlic breath. By the use
of headspace technique they identified two major
sulphur compounds in exhaled air - allyl mercaptan
(2-propene-1-thiol) and diallyl disulphide. Minami
et al later confirmed allyl mercaptan as the
major garlic-borne compound while diallyl disulphide
In a later study by Ruiz
et al, the breath concentrations of various
allylic sulphur-containing garlic-borne phytochemicals
were measured and their results are summarised
in Figure 2. Levels of methyl
allyl sulphide, allyl thiol, diallyl sulphide
and diallyl disulphide were all originally high
but found to drop precipitously within a relatively
short period of time (1-3 hours). The slope of
the curves changes dramatically by leveling off
and remaining constant throughout the rest of
the sampling interval. It is believed that the
initial high levels and rapid decline of the sulphur
compounds are related to their elimination from
the oral and pharyngeal regions where they are
present as residues immediately after the ingestion
of garlic. The leveling off region is claimed
to represent bloodstream elimination of the compounds
via gas exchange in the lungs. The trials conducted
by Ruiz et aI confirmed that the time taken for
the change coincided with the time expected for
digestion and bloodstream absorption.
2. Breath concentrations of various compounds
after ingestion of fresh garlic (Ruiz et al.)
the residual levels of sulphides and allyl mercaptan
appear low, sensitivity to these compounds is
high with detection levels in ppm and even ppb.
Sakai Garlic - mode of action.
processes described in Sakai's patent involve
soaking the garlic bulbs in a deodorising solution
containing mesoinositol hexaphosphate and silicic
acid. The bulbs become impregnated with the solution
and are then dried before use.
In the patent Sakai attributes the malodour of
garlic to the combination of sulphides and mercaptans
generated by the garlic within the bulb and presumably
also after crushing and ingestion. He goes on
to state that alliin (S-allyl-L-cysteine sulphoxide),
the precursor to the formation of allicin when
garlic tissue is ruptured, undergoes an enzymatic
decomposition within intact garlic tissue to form
a compound called aricine (16,17-didehydro-10-methoxy-19a-methyloxayohimban-16-carboxylic
acid) and that it is as a result of this decomposition
of alliin to aricine that mercaptans are formed.
The patent claims that the mesoinositol hexaphosphate
has the effect of coagulating the enzyme that
is responsible for the alliin to aricine reaction
thereby significantly reducing the levels of mercaptan.
It further claims that the process involves increasing
the temperature of the deodorising solution (in
which the bulbs are soaked) and that this causes
a vigorous enzymatic formation of mercaptans within
the garlic tissue. Subsequent lowering of the
temperature and the introduction of pressure differentials
cause the deodorising solution to be taken up
and to act upon the cell contents. The silicic
acid 'mops up' the free sulphides (including mercaptans)
while the mesoinositol hexaphosphate acts upon
the enzyme that causes mercaptans to be generated.
The final stage of the process involves again
reversing osmotic pressures so that the 'spent'
deodorising solution is removed. The bulbs are
then dried and processed in the normal way.
states that the malodour associated with garlic
is due to a combination of sulphides and mercaptan.
This is supported by the research paper published
by Minami et al (1989)
who confirmed that the major compounds in exhaled
air were primarily allyl mercaptan with diallyl
disulphide as a secondary contributor.
The mechanisms described by Sakai are more challenging
and these specific pathways are at present beyond
the scope of this study.
R. Yamamoto of Ricom
Corporation of Japan has independently tested
Sakai garlic and whilst the results are not statistically
valid, they do give an indication of the effectiveness
of the Sakai product. Note that the results were
obtained from subjects who held garlic in their
mouths and did not ingest so the compounds measured
will be principally from garlic tissue retained
in the mouth and on the teeth and not from gas
exchange via the lungs.