A total of 350 ingredients, commonly used in various combinations
and in a limited number in a given brand in the manufacture of marketed kretek cigarettes, were assigned to three different
ingredient mixes, i.e., Mix A, Mix B, and Mix C (see Appendix,
Table A). The ingredients were introduced in the respective mix
at a low and a high target level. The addition levels to these test
cigarettes were the typical use level and either 2.5 (licorice extract
and invert sugar) or three times the use level. The mixes were
added to experimental cigarettes containing, beside the Indonesian
tobacco, 31% cut cloves and 1.7% humectants (propylene glycol,
glycerin, and D-sorbitol) as filler, similar to the Kretek-R reported
earlier (Piadé et al., 2014). Further details on the cigarettes can
be found in Table 1. As the cigarettes were manufactured to a constant
weight, the ingredients partly replaced the filler. They were
added to the filler at that point in the cigarette production process
(casing and after-cut) where they are normally added in the industrial
fabrication process, some ingredients were therefore added to
more than one mix. There were differences in target/addition concentrations
of the individual ingredients concentrations in tobacco
and those after the manufacturing process. These differences were
considered to represent normal manufacturing losses due to evaporation
or chemical interaction with tobacco components.