The objective ofthis work is to develop a method to get the protein composition of latex. Additionally to the extraction method itself, different preservation methods ofwhole latex (WL) were tested to prevent latex from any deterioration and/or destabilization (which might induce protein degradation) during the time elapsed between latex collection in the field and protein analysis in the laboratory. These treatments include: stabilization ofwhole latex with an adequate buffer to generate stabilized latex (SL) as well as freezing WL and SL in liquid nitrogen to generate frozen whole latex (FWL) and frozen stabilized latex (FSL), respectively. Proteins were extracted using three extraction buffers of different compositions and the protein composition was revealed by one-dimensional gel electrophoresis (SDS-PAGE). The SDS-PAGE gels were studied by image analysis to provide qualitative and quantitative information on protein content. The comparison of the SDS-PAGE gels allowed us to determine the most appropriatepreservation method oflatex (i.e. stabilizing latex and freezing stabilized latex for short and long storage periods, respectively) as well as to determine the most efficient protein extraction buffer (i.e. 100 mM Tris, 100 mM EDTA, 10% glycerol, 2% Triton X-100, 20 mM DTT and 2 mM PMSF, pH 8).