Okra extracts as emulsifiers for acidic emulsions

K. Alba, C. Ritzoulis, N. Georgiadis, V. Kontogiorgos

Research output: Contribution to journalArticle

38 Citations (Scopus)

Abstract

Extracts rich in pectins were isolated by aqueous extraction at pH. 4.0 (OE4) and 6.0 (OE6) from okra (Abelmoschus esculentus) pods. They were examined in terms of their composition and emulsion stabilizing capacity in model acidic emulsions (hexadecane-in-water at pH. 3.0). Extracted polysaccharides were assessed using size exclusion chromatography (SEC) and FTIR spectroscopy. The properties and stability of the resulting emulsions were examined by means of droplet size distribution and ζ-potential measurements, viscometry, fluorescence microscopy and protein interface concentration. As emulsifiers, both extracts produce emulsions of initially monomodal size distribution and of similar average droplet size, while ζ-potential was negative for both. The emulsions prepared using OE6 are relatively stable in terms of droplet size distribution and average droplet size after 30. days of storage, while emulsions prepared with OE4 increase in droplet size, in part attributable to Ostwald ripening. Determination of the protein interface coverage Γsuggests that the increased stability of the OE6 emulsions should be attributed to the higher protein load of the interfaces prepared using this extract, resulting to increased rigidity of the interface. Viscosity of emulsions containing OE6 was two times greater than OE4 while aging increases the viscosity of both emulsions. The present work suggests that okra extracts can be strong candidates for emulsification in acidic environments.

LanguageEnglish
Pages1730-1737
Number of pages8
JournalFood Research International
Volume54
Issue number2
DOIs
Publication statusPublished - Dec 2013

Fingerprint

Abelmoschus
okra
emulsifiers
Emulsions
emulsions
droplet size
extracts
Viscosity
viscosity
Pectins
viscometry
hexadecane
Abelmoschus esculentus
application coverage
Proteins
proteins
emulsifying
Fourier Transform Infrared Spectroscopy
fluorescence microscopy
Fluorescence Microscopy

Cite this

Alba, K. ; Ritzoulis, C. ; Georgiadis, N. ; Kontogiorgos, V. / Okra extracts as emulsifiers for acidic emulsions. In: Food Research International. 2013 ; Vol. 54, No. 2. pp. 1730-1737.
@article{b2418026fc6a4ca28eed881c29bf2b5f,
title = "Okra extracts as emulsifiers for acidic emulsions",
abstract = "Extracts rich in pectins were isolated by aqueous extraction at pH. 4.0 (OE4) and 6.0 (OE6) from okra (Abelmoschus esculentus) pods. They were examined in terms of their composition and emulsion stabilizing capacity in model acidic emulsions (hexadecane-in-water at pH. 3.0). Extracted polysaccharides were assessed using size exclusion chromatography (SEC) and FTIR spectroscopy. The properties and stability of the resulting emulsions were examined by means of droplet size distribution and ζ-potential measurements, viscometry, fluorescence microscopy and protein interface concentration. As emulsifiers, both extracts produce emulsions of initially monomodal size distribution and of similar average droplet size, while ζ-potential was negative for both. The emulsions prepared using OE6 are relatively stable in terms of droplet size distribution and average droplet size after 30. days of storage, while emulsions prepared with OE4 increase in droplet size, in part attributable to Ostwald ripening. Determination of the protein interface coverage Γsuggests that the increased stability of the OE6 emulsions should be attributed to the higher protein load of the interfaces prepared using this extract, resulting to increased rigidity of the interface. Viscosity of emulsions containing OE6 was two times greater than OE4 while aging increases the viscosity of both emulsions. The present work suggests that okra extracts can be strong candidates for emulsification in acidic environments.",
keywords = "Emulsions, Microscopy, Okra, Ostwald ripening, Pectins, Rheology",
author = "K. Alba and C. Ritzoulis and N. Georgiadis and V. Kontogiorgos",
year = "2013",
month = "12",
doi = "10.1016/j.foodres.2013.09.051",
language = "English",
volume = "54",
pages = "1730--1737",
journal = "Food Research International",
issn = "0963-9969",
publisher = "Elsevier Limited",
number = "2",

}

Okra extracts as emulsifiers for acidic emulsions. / Alba, K.; Ritzoulis, C.; Georgiadis, N.; Kontogiorgos, V.

In: Food Research International, Vol. 54, No. 2, 12.2013, p. 1730-1737.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Okra extracts as emulsifiers for acidic emulsions

AU - Alba, K.

AU - Ritzoulis, C.

AU - Georgiadis, N.

AU - Kontogiorgos, V.

PY - 2013/12

Y1 - 2013/12

N2 - Extracts rich in pectins were isolated by aqueous extraction at pH. 4.0 (OE4) and 6.0 (OE6) from okra (Abelmoschus esculentus) pods. They were examined in terms of their composition and emulsion stabilizing capacity in model acidic emulsions (hexadecane-in-water at pH. 3.0). Extracted polysaccharides were assessed using size exclusion chromatography (SEC) and FTIR spectroscopy. The properties and stability of the resulting emulsions were examined by means of droplet size distribution and ζ-potential measurements, viscometry, fluorescence microscopy and protein interface concentration. As emulsifiers, both extracts produce emulsions of initially monomodal size distribution and of similar average droplet size, while ζ-potential was negative for both. The emulsions prepared using OE6 are relatively stable in terms of droplet size distribution and average droplet size after 30. days of storage, while emulsions prepared with OE4 increase in droplet size, in part attributable to Ostwald ripening. Determination of the protein interface coverage Γsuggests that the increased stability of the OE6 emulsions should be attributed to the higher protein load of the interfaces prepared using this extract, resulting to increased rigidity of the interface. Viscosity of emulsions containing OE6 was two times greater than OE4 while aging increases the viscosity of both emulsions. The present work suggests that okra extracts can be strong candidates for emulsification in acidic environments.

AB - Extracts rich in pectins were isolated by aqueous extraction at pH. 4.0 (OE4) and 6.0 (OE6) from okra (Abelmoschus esculentus) pods. They were examined in terms of their composition and emulsion stabilizing capacity in model acidic emulsions (hexadecane-in-water at pH. 3.0). Extracted polysaccharides were assessed using size exclusion chromatography (SEC) and FTIR spectroscopy. The properties and stability of the resulting emulsions were examined by means of droplet size distribution and ζ-potential measurements, viscometry, fluorescence microscopy and protein interface concentration. As emulsifiers, both extracts produce emulsions of initially monomodal size distribution and of similar average droplet size, while ζ-potential was negative for both. The emulsions prepared using OE6 are relatively stable in terms of droplet size distribution and average droplet size after 30. days of storage, while emulsions prepared with OE4 increase in droplet size, in part attributable to Ostwald ripening. Determination of the protein interface coverage Γsuggests that the increased stability of the OE6 emulsions should be attributed to the higher protein load of the interfaces prepared using this extract, resulting to increased rigidity of the interface. Viscosity of emulsions containing OE6 was two times greater than OE4 while aging increases the viscosity of both emulsions. The present work suggests that okra extracts can be strong candidates for emulsification in acidic environments.

KW - Emulsions

KW - Microscopy

KW - Okra

KW - Ostwald ripening

KW - Pectins

KW - Rheology

UR - http://www.scopus.com/inward/record.url?scp=84887165180&partnerID=8YFLogxK

U2 - 10.1016/j.foodres.2013.09.051

DO - 10.1016/j.foodres.2013.09.051

M3 - Article

VL - 54

SP - 1730

EP - 1737

JO - Food Research International

T2 - Food Research International

JF - Food Research International

SN - 0963-9969

IS - 2

ER -