Rheological characterisation of aqueous extracts of triticale grains and its relation to dietary fibre characteristics

Rheological properties of triticale extract are important determinants of the grain utility. Extracts of eight triticale cultivars and a wheat reference grown at two different locations i.e. Svalov and Kolback were analysed for their viscoelastic properties. Extracts of triticale cultivars grown at Svalov were significantly higher in elastic modulus (average 9.0 Pa), viscous modulus (average 12.7 Pa) and complex modulus (average 15.6 Pa) at 2.1 Hz than those grown at Kolback (average 3.1, 5.6 and 6.4 Pa, respectively). However phase angle was not affected by location, and all triticale extracts had phase angle >45 degrees. Large inter-cultivar variation was also observed in viscoelastic properties of triticale extracts. Some of the triticale cultivars grown at Kolback (Dinaro, Cando, Talentro, and DED 145/02) and Svalov (DED 145/02) were similar to wheat in their complex modulus values. When evaluating the contribution of arabinoxylan (AX) and beta-glucan to theological properties of triticale extracts by partial least square (PLS) regression, it was evident that beta-glucan had little role and most of the contribution to viscoelastic properties came from AX. AX fine structure was more important in explaining variation in complex modulus of triticale extract than content and extractability, or molecular size. (C) 2012 Elsevier Ltd. All rights reserved.