Three types of plastic material (Saran, Tedlar and Teflon) were examined fo
r their influence on the profile of a model headspace containing 13 volatil
e compounds of different volatility and polarity. As far as the emission of
contaminants from the bags to the headspace is considered, the most approp
riate material is obviously Teflon. However, the drawback of this material
is a rapid sorption and then a slow adsorption of most volatile compounds t
ested. in particular polar ones. The authors suggest that acceptable time f
or headspace storage is between 4 and 12 hours, but with possible loss of t
he most polar compounds present in trace quantities.