European Food Research and Technology

, Volume 227, Issue 2, pp 425–431

Antioxidant capacity of walnut (Juglans regia L.): contribution of oil and defatted matter

  • Sara Arranz
  • Jara Pérez-Jiménez
  • Fulgencio Saura-Calixto
Original Paper

DOI: 10.1007/s00217-007-0737-2

Cite this article as:
Arranz, S., Pérez-Jiménez, J. & Saura-Calixto, F. Eur Food Res Technol (2008) 227: 425. doi:10.1007/s00217-007-0737-2

Abstract

Several studies have concluded that walnut exhibits greater antioxidant capacity than any other nuts. However, the contribution to antioxidant capacity of the two major fractions of walnut (defatted matter and oil) is unknown, and the aim of the present work is to elucidate it. Antioxidant capacity was evaluated in walnut oil, defatted matter, and whole walnut. The results showed that the defatted matter provided the bulk of the antioxidant capacity (estimated about 332 μmol Trolox/g dm) of this nut, a major proportion derived from insoluble tannins. The contribution of walnut oil to the overall antioxidant capacity of walnut (FRAP and ABTS assays) is less than a 5%. It was observed that oil interfered in the determination of antioxidant capacity of whole walnut, a fact that could affect the data reported in the literature. Separate determination of oil and defatted mater antioxidant capacity is recommended.

Keywords

Defatted matterAntioxidantsWalnutOilJuglans regia L.

Abbreviations

ABTS

2,2′-Azino-bis(3-ethylbenz-thiazoline-6-sulfonic acid)

AE

Antiradical efficiency

CUPRAC

Cupric reducing/antioxidant capacity

DPPH

2,2 Diphenyl-1-picrylhydrazyl

FRAP

Ferric reducing/antioxidant power

LDLs

Low-density lipoproteins

ORAC

Oxygen radical absorbance capacity

TBARs

Thiobarbituric acid reactive substances

TRAP

Total peroxyl radical trapping antioxidant activity

Copyright information

© Springer-Verlag 2007

Authors and Affiliations

  • Sara Arranz
    • 1
  • Jara Pérez-Jiménez
    • 1
  • Fulgencio Saura-Calixto
    • 1
  1. 1.Department of Metabolism and NutritionInstituto del Frío, CSICMadridSpain