Cartapip™: a biopulping product for control of pitch and resin acid problems in pulp mills

This paper addresses a biological treatment of wood chips using specific isolants of the ascomycete, Ophiostoma piliferum, which results in a reduced extractive content, specifically pitch also known as resin, of the wood chips. Natural isolants of O. piliferum cause blue stain in the sapwood of conifers. Colorless isolants of O. piliferum, isolated in the laboratory, marketed as Cartapip™ have been shown not to cause discoloration of wood. Hyphae preferentially colonize ray parenchyma cells and resin canals. Studies have shown that not only does overall pitch content decrease with treatment of wood chips by the O. piliferum strains tested, but also many free resin acids and fatty acids are significantly reduced. Additionally, treatment of wood chips with the colorless strains of O. piliferum results in biocontrol since other microorganisms including staining organisms have significantly reduced growth on the wood chips. Therefore bleach chemicals can be saved in the processing of mechanical pulp to give higher brightness paper.