ABSTRACT
The main component of the soluble dietary fiber of oat is β-glucan. Research on oat has been intensified in the last few years. In clinical studies, oat β-glucan was shown to reduce serum cholesterol levels and attenuate postprandial blood glucose and insulin responses in a viscosityrelated fashion. Oat is extensively planted as a forage crop in Northern Mexico, where drought resulted in a lower oat seed quality crop which failed to meet the requirements of the market. In this chapter, β-glucan from a low-quality oat variety was extracted and characterized for the first time as a potential gelling agent for the food industry. β-glucan presented an intrinsic viscosity ([η]) of 315 ml/g and a viscosimetric molecular weight (Mv) of 369 kDa. Fourier-transform infrared spectroscopy spectrum of β-glucan shows the main band centered at 1035 cm−1 which could be assigned to C-OH bending, with shoulders at 1158, 995, and 897 cm−1 that were related to the antisymmetric C-O-C stretching mode of the glycosidic link and β,(1-4) linkages. The gelling capability of β-glucans at 10%·w/v was investigated by rheological measurements. G′ and G″ attained the respective plateau values of 155 and 51 Pa after an induction period. The gel set time (G′>G″) corresponded to 20 h. The results attained suggest that β-glucans from low-quality oat can be a potential source of a gelling polysaccharide for the food industry.
