Ms. Lumme et al., The effects of hydrolytic enzyme treatments on three British Columbian interior fir kraft pulps differing in their initial fiber coarseness, WOOD FIB SC, 31(4), 1999, pp. 385-393
The effects of carbohydrate-degrading enzymes on three softwood kraft pulps
, differing primarily in their initial fiber coarseness, were assessed. The
pulps were treated with three different enzyme preparations (a crude cellu
lase, an endoglucanase, and a xylanase) to assess the potential of the diff
erent enzymes to alter handsheet properties and to evaluate their effects o
n fiber coarseness. All enzymatic treatments increased handsheet densities
irrespective of the furnish used. The most significant modifications in han
dsheet properties were evident after treatment with either the crude cellul
ase or the endoglucanase. Although increased densification occurred with al
l the pulps, the degree of fiber coarseness of the original pulp influenced
the magnitude of response to the different enzymatic treatments. While the
tensile index of the coarser pulp was improved by treatment with the crude
cellulase, a similar trend was not evident with the pulps of lower coarsen
ess. In contrast, the tensile strength of all pulps, irrespective of the in
herent fiber coarseness, was improved by the endoglucanase treatments. The
tear strength decreased after treatments with both the crude cellulase and
endoglucanase. Xylanase treatments did not significantly alter the handshee
t properties of any of the pulps, regardless of the nature of the starting
furnish.