Tannin-resorcinol-formaldehyde cold-set adhesives for wood laminating and fingerjointing were examined by Matrix Assisted Laser Desorption/Ionisation Time of Flight (MALDI-TOF) mass spectrometry. The analysis revealed that the adhesive was composed at the gel point of resorcinol-formaldehyde oligomers, unreacted flavonoids, and resorcinol-formaldehyde oligomers coreacted with flavonoid units of the tannin. The last ones constitute a high proportion of the adhesive resin. Furthermore, their proportion is highest at the minimum phenolic reactivity around pH 4. (C) Koninklijke Brill NV, Leiden, 2012