Rheological characterization of okra pectins

V. Kontogiorgos, I. Margelou, N. Georgiadis, C. Ritzoulis

Research output: Contribution to journalArticle

59 Citations (Scopus)

Abstract

Polysaccharides from okra pods (. Abelmoschus esculentus) were extracted using a sequential extraction protocol and compared with a simple extraction at pH 6. Rheological properties of three okra extracts were then investigated by means of molecular weight determination, dilute solution rheology, steady shear and oscillatory rheological measurements. The extraction protocols resulted in extracts of relatively high purity and multimodal molecular weight distribution. Furthermore, molecular parameters of the isolated biopolymers such as intrinsic viscosity, Huggins constant, critical concentration and coil overlap parameter were calculated from dilute solution viscometry. Investigation of the generalized flow behaviour using a modified Cross equation and Cox-Merz plots showed evidence that as concentration increases specific interactions start taking place among the polymeric chains that modify the rheological behaviour of the extracts. The change in the rheological behaviour could not only be explained by differences in the molecular weight of the samples but also should be attributed to the fine structure of the chains that are obtained under the different extraction protocols. Present investigation shows that further optimization of such protocols may result in polysaccharide fractions with specific rheological properties.

LanguageEnglish
Pages356-362
Number of pages7
JournalFood Hydrocolloids
Volume29
Issue number2
DOIs
Publication statusPublished - 1 Dec 2012

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Abelmoschus
Pectins
okra
pectins
Molecular Weight
Polysaccharides
molecular weight
rheological properties
extracts
Biopolymers
polysaccharides
Rheology
Molecular weight
viscometry
Viscosity
Abelmoschus esculentus
Viscosity measurement
biopolymers
rheology
Molecular weight distribution

Cite this

Kontogiorgos, V. ; Margelou, I. ; Georgiadis, N. ; Ritzoulis, C. / Rheological characterization of okra pectins. In: Food Hydrocolloids. 2012 ; Vol. 29, No. 2. pp. 356-362.
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Kontogiorgos, V, Margelou, I, Georgiadis, N & Ritzoulis, C 2012, 'Rheological characterization of okra pectins', Food Hydrocolloids, vol. 29, no. 2, pp. 356-362. https://doi.org/10.1016/j.foodhyd.2012.04.003

Rheological characterization of okra pectins. / Kontogiorgos, V.; Margelou, I.; Georgiadis, N.; Ritzoulis, C.

In: Food Hydrocolloids, Vol. 29, No. 2, 01.12.2012, p. 356-362.

Research output: Contribution to journalArticle

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