Delignification of Fibrous Wastes by Peroxyacetic Acid Treatments

Abstract

Ponderosa pine wood chips and bark, straws (wheat, rice and barley), sugar cane bagasse and pineapple leaves were subjected to various peroxyacetic acid delignification treatments to improve digestibility. Digestibility was estimated by in vitro methods using either fresh rumen fluid or isolated cellulase preparations. Digestibility increases were proportional to the concentration of peroxyacetic acid used. In comparison treatments involving equal amounts of peroxyacetic acid, the chemical lost effectiveness with dilution. Although almost complete delignification can be achieved by treatment, it appears that 60% delignification would be most practical for preparation of ruminant feeds. Effective delignification requires 40 to 70 g of peroxyacetic acid per gram of substrate. At present, treatment costs could prohibit practical usage. Rice straws are the least responsive to peroxyacetic acid treatment since fiber encrustation results largely from silica rather than lignin. Safety precautions for synthesis and use of this chemical are suggested. Copyright © 1980. American Society of Animal Science . Copyright 1980 by American Society of Animal Science.