Published in

American Chemical Society, Journal of Agricultural and Food Chemistry, 22(59), p. 12018-12027, 2011

DOI: 10.1021/jf203582k

Links

Tools

Export citation

Search in Google Scholar

Identification and Thermal Degradation Kinetics of Chlorophyll Pigments and Ascorbic Acid from Ditax Nectar (Detarium senegalense J.F. Gmel)

This paper was not found in any repository; the policy of its publisher is unknown or unclear.
This paper was not found in any repository; the policy of its publisher is unknown or unclear.

Full text: Unavailable

Green circle
Preprint: archiving allowed
  • Must obtain written permission from Editor
  • Must not violate ACS ethical Guidelines
Orange circle
Postprint: archiving restricted
  • Must obtain written permission from Editor
  • Must not violate ACS ethical Guidelines
Red circle
Published version: archiving forbidden
Data provided by SHERPA/RoMEO

Abstract

Detarium senegalense J.F. Gmel (ditax) is a forest tree found in Senegal the fruits of which are characterized by an attractive green flesh with a high amount in ascorbic acid. It is generally consumed as a nectar in Senegal. In this study, the main pigments of ditax pulp were identified and quantified by HPLC-DAD. Pheophytin a (128 mg/kg), which represents 58% of the total pigments, followed by hydroxypheophytin a0 (33 mg/kg), chlorophyll b (24 mg/kg), and chlorophyll a (20 mg/kg) was the major pigment of ditax pulp. Lutein and ?-carotene were present in lower amounts (4.6 and 3.6 mg/kg, respectively). The thermal degradation kinetics of pheophytin a, hydroxypheophytin a0, and ascorbic acid were determined at temperatures ranging from 60 to 95 _C in ditax nectar. Pheophytin a was the most heat sensitive. Thermal processing induced the formation of degradation products such as pyropheophytin a and pyropheophytin b. The kinetics parameters have been calculated according to the models of Arrhenius, Eyring, and Ball. Following the Arrhenius relation, activation energies of pheophytin a, hydroxypheophytin a0, and ascorbic acid were, respectively, 79, 74, and 46 kJ mol_1. Losses calculated during isothermal treatments were close to experimental losses in pheophytin a, hydroxypheophytin a0, and ascorbic acid. The Eyring model can then be used to predict chlorophyll pigments and vitamin C losses during pasteurization of the nectar (