Effect of dielectric microwave heating on the color and antiradical capacity of betanin

Author(s)

Pires Goncalves, Leticia Christina ^[1] ; Di Genova, Bruno Martorelli ^[1] ; Doerr, Felipe Augusto ^[2] ; Pinto, Ernani ^[2] ; Bastos, Erick Leite ^[3]

Affiliation

^[1] Univ Fed ABC, Ctr Ciencias Nat & Humanas, Santo Andre, SP - Brazil

^[2] Univ Sao Paulo, Fac Ciencias Farmaceut, Dept Anal Clin & Toxicol, Sao Paulo - Brazil

^[3] Univ Sao Paulo, Inst Quim, Dept Quim Fundamental, Sao Paulo - Brazil

• Document type: Journal article
• Source: Journal of Food Engineering; v. 118, n. 1, p. 49-55, SEP 2013.
• Web of Science Citations: 18

Abstract

The decomposition of betanin under dielectric heating (microwave irradiation, power: 25-200 W (3-24 kJ g(-1))) follows first-order kinetics with a rate constant similar to that obtained during conventional conduction heating (half-life < 2 min at 100 degrees C). Color coordinate analysis indicates that betanin is bleached upon thermal treatment, whereas beetroot juice and spray-dried beetroot powder tend to form colored decomposition products. The antiradical capacity of betanin decreases upon heating, but is still much higher than that of standard antioxidants such as ascorbic acid and trolox. Betalamic acid, a high capacity antiradical, was detected by mass spectrometry and second-derivative absorption spectroscopy in betanin samples submitted to thermal treatment. (C) 2013 Elsevier Ltd. All rights reserved. (AU)

• FAPESP's process: 07/59407-1 - Semi-synthetic betalains as biocompatible antioxidants and pigments
• Grantee: Leticia Christina Pires Gonçalves
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• FAPESP's process: 07/00684-6 - Synthesis and application of modified flower pigments
• Grantee: Erick Leite Bastos
• Support Opportunities: Research Grants - Young Investigators Grants