Alpha-L-arabinofuranosidase involved in the degradation of arabinoxylan, a major component of plant hemicellulose. Acts only on small linear 1,5-alpha-linked L-arabinofuranosyl oligosaccharides (By similarity). Hydrolysis of terminal non-reducing alpha-L-arabinofuranoside residues in alpha-L-arabinosides. Glycan metabolism; L-arabinan degradation. Belongs to the glycosyl hydrolase 51 family.