Role of pectic polysaccharides in structural integrity of apple cell wall material |
| |
Authors: | Robert J Redgwell Delphine Curti Cécile Gehin-Delval |
| |
Affiliation: | (1) Nestlé Research Centre, Vers-Chez-Les-Blanc, 1000 Lausanne 26, Switzerland |
| |
Abstract: | Texture modulating properties of aqueous dispersions of apple cell wall material differed from those of tomato or kiwifruit,
particularly under high shear. It was previously hypothesized that this may be due to the fact that the apple cell wall showed
less in vivo solubilization of pectic polysaccharides during ripening compared to tomato or kiwifruit. However, in vitro solubilization
of the pectic polysaccharide content of apple CWM by endo-polygalacturonase and/or extraction with 0.05 M sodium carbonate,
did not affect the loss in wall integrity shown by tomato or kiwifruit CWMs under shear. In addition, the pectin-depleted
residue after Na2CO3 extraction possessed better water retaining and viscosity generating properties than the original cell wall material. Following
treatment of apple CWM with cellulase, the viscosity of suspensions decreased, emphasising the role that the cellulose–hemicellulose
network plays in the water-retaining capacity of the cell wall. Residue from CWM after cellulase treatment consisted of ∼85%
pectic polysaccharides. Surprisingly, the integrity of these “cellulose-free” walls was maintained after shear. It is concluded
that differences in structural properties of the CWMs of apple compared to kiwifruit or tomato are not simply related to pectin
solubilization but to a fundamental difference in the architecture of the apple cell wall. |
| |
Keywords: | Apple Cell wall material Pectic polysaccharides Viscosity |
本文献已被 SpringerLink 等数据库收录! |
|