Water‐holding capacity of insoluble fibre decreases free water and elevates digesta viscosity in the rat

Abstract

BACKGROUND:The relationships between possible physiological properties of insoluble fibre and the viscosity of digesta are poorly understood. The aim of this study was to investigate the effect of insoluble fibres with different water-holding capacity, swelling, oil-holding capacity and cation exchange capacity on gastric, small intestinal and caecal contents in rats fed a semi-purified diet containing either no fibre (control), 50 g kg −1 tossa jute fibre or 50 g kg −1 shiitake fibre.

Acute effects of pea protein and hull fibre alone and combined on blood glucose, appetite, and food intake in healthy young men – a randomized crossover trial

“…Insoluble dietary fibre has high waterholding capacity (13.4 mL/g) (Dalgetty et al 2003;Tiwari et al 2011), which increases in pea hulls after grinding because of the increased surface area and pore volume (Auffret et al 1994). In a study with rats, insoluble fibre decreased free water content and increased the viscosity of digesta (Takahashi et al 2009), which can mimic the effect of viscous fibre and affect the postprandial glucose absorption. This is also supported by another study where pea hull fibre ingestion by healthy volunteers led to the long orocaecal transit time, which is an indicator of small intestinal transit time (Cherbut et al 1991).…”

Physicochemical properties to support fibre characterization in monogastric animal nutrition

“…Among physicochemical properties, hydration capacity (HC) 5 and buffering capacity 7 have been identified to play key roles. Although measured regularly in several publications, [8][9][10][11][12][13] physicochemical properties are seldom considered for the identification of fibre types, and are rarely used in diet formulation. Therefore, fibre characterization in the diet needs an approach, which may include also physicochemical properties to explain variation in digestion, in competing processes of digestion and in digesta transit.…”

Fiber

“…Swelling is related to the relative volume of particles dispersed in a liquid medium, such as the contents of the intestinal lumen. Water retention is physiologically relevant because the centrifugation-resistant retained water approximates bound water, which contributes to the effective volume of hydrated cell-wall remnants in the gut, while it reduces free water content, which is important in viscosity (Takahashi et al, 2009). Water retention is physiologically relevant because the centrifugation-resistant retained water approximates bound water, which contributes to the effective volume of hydrated cell-wall remnants in the gut, while it reduces free water content, which is important in viscosity (Takahashi et al, 2009).…”