One of the major by-products of bioethanol production is distillers dried
grains with solubles (DDGS). Maize is one of the main sources for the production of
this biofuel. In this way, dietary fiber represents the principal fraction of DDGS, which
could be a potential source of added-value biomolecules such as ferulated
arabinoxylans (AX). In this chapter, ferulated arabinoxylans extracted from DDGS
(DDGAX) were gelled and the gels were studied in terms of rheology, structural
parameters and microstructural characteristics. The DDGAX formed gels at 2% (w/v)
induced by laccase. The mechanical spectrum and strain sweep of DDGAX gel
presented the typical behavior of a solid-like material. The gels swelling ratio (43 g
water/g DDGAX) suggested the formation of a compact polymeric network which
decreased the water uptake of the gel. DDGAX gels presented an average mesh size
value of 96 nm. The surface of the gels was analyzed by scanning electron microscopy
revealing a heterogeneous microstructure resembling an imperfect honeycomb. These
results indicate that ferulated arabinoxylans from DDGS form elastic and macroporous
gels, presenting a microstructure with irregular pore sizes.
Keywords: Arabinoxylan gels, Ferulic acid, Gelling capability, Microstructure,
Structural properties, Swelling.
