I can only think of the following approach:

Use a sealable-glass test tubes (screw-capped or more) carrying a fixed amount of "charcoal" to trap the volatiles; and keep weighing and throwing the fruiting body into the tubes as you go on in the field. Back tot he lab- then wash the charcoal in pentane, hexane, and further down to see which fractions trap what kind of volatiles.

Avoid precision, but do not ignore accuracy- as different amount of fruiting bodies will emitt different VOC amounts- unless you are just interested in qualitative analysis of VOC types. : )

Just regular charcoal? Does it have to be processed in some way? (i.e. sterilization).

Also, thanks for the response. I'd like to ask you if there's a published source describing the method, for the corresponding citation in future research.

Well activated charcoal, but for safety you may clean/wash them up with hexane and dry out in a oven safely etc.

See papers: https://scholar.google.com/scholar?hl=en&as_sdt=0%2C34&q=charcoal+VOC+trap&btnG= it is a known matrix for trapping VOCs in commercial kits and columns etc as well. You can cite some popular ones as well.

Cristian,

check the term "sorption tubes". Activated carbon is not the best solution.

Depending on the type and volatility range of VOCs you chould use TENAX sorbent or a sequencial bed with TENAX and stronger adsorbent like carbosieve.

regards,

G