Extrusion improved the physical and chemical properties of dietary fibre from bamboo shoot by-products

摘要

Bamboo shoot by-products are regarded as waste and environmental pollutant. This study aimed to improve the functional properties of dietary fibre from bamboo shoot by-products. After CO_2 extrusion, the particle size of CO_2-extruded bamboo fibre was 17.6% lower than that of the control, and its specific surface area was 2.85 times that of the control. The soluble dietary fibre content was significantly increased from 5.64 g/100 g to 11.05 g/100 g (P ＜ 0.05), and the capacities for water holding, swelling and oil holding were remarkably improved. The cholesterol adsorption of CO_2-extruded bamboo fibre was increased from 96.54 μg g~(-1) to 174.65 μg g~(-1) (pH 7.0), and its nitrite ion adsorption capacity was increased from 503.33 μg g~(-1) to 657.27 μg g~(-1) (pH 2.0). In summary, the structural changes of bamboo fibre such as internal porosity, surface roughening and low crystallinity indicated that its functional properties were improved after CO_2 extrusion.