Chain conformations and steady-shear viscosity properties of pectic polysaccharides from apple and tomato

Steady and transient rheological properties of four polysaccharides with different chain conformations

“…However, as the shear rate is increased further, the larger shear force disrupts the aggregate structure, leading to shear‐thinning pseudoplastic fluid properties 54 . Recently, apple pectin in water containing NaNO 3 was also observed to exhibit shear‐thickening behavior in the shear rate range of < 1 s −1 , which was attributed to the disruption of the ordered arrangement induced by semi‐rigid pectin chains into randomly entangled structure by weak shear force 36 . It has been demonstrated that lentinan chains with such relatively low molecular weight as M w = 46.1 × 10 4 align to form bundles of sticks in water because of the strong stiffness and hydrogen bonding of lentinan 55 .…”

“…54 Recently, apple pectin in water containing NaNO 3 was also observed to exhibit shear-thickening behavior in the shear rate range of < 1 s À1 , which was attributed to the disruption of the ordered arrangement induced by semi-rigid pectin chains into randomly entangled structure by weak shear force. 36 It has been demonstrated that lentinan chains with such relatively low molecular weight as M w = 46.1 Â 10 4 align to form bundles of sticks in water because of the strong stiffness and hydrogen bonding of lentinan. 55 In this work, it is thus speculated that the stiff polysaccharides with helix chain conformation formed bundles at certain concentrations because of the strong stiffness and hydrogen bonding among hydroxyl groups.…”

“…35 From the reported literatures on rheology of these four polysaccharides, it is found that the used shear rate range usually starts from 0.1 s À1 and that the steady-shear rheological behaviors of polysaccharides at the shear rate of < 0.1 s À1 have been seldom reported. In our recent work, the shear-thickening behavior of apple pectin with semirigid chain conformation was observed in the shear rate range of < 0.1 s À1 , 36 which triggered us to investigate the effect of chain conformation on the steady-shear rheological properties of polysaccharides with different conformations. Curdlan, xanthan, lentinan and pullulan with different chain conformations from triple helix to random coils were thus chosen for this purpose.…”

Pectin in Metabolic Liver Disease

“…Conversely, soluble fiber, such as pectin, gums, xyloglucans, inulin, maltodextrins, starch and polydextrose are highly fermentable by bacteria of the large intestine [ 19 ]. Soluble fiber is found in vegetables, whole grains, such as oats and barley, and fruits, in particular, the peels of apples and citrus, which are highly enriched in pectin ( Table 1 [ 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 ]).…”