ESR study on identification of gamma-irradiated kiwi, papaya and tomato using fruit pulp

• Published in: International journal of food science & technology Vol. 34; no. 2; pp. 173 - 178
• Main Authors: Jesus, E.F.O. de, Rossi, A.M, Lopes, R.T
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Science Ltd 01-04-1999; Blackwell Science
• Subjects: alcohols; Biological and medical sciences; detection; dosage; dose determination; electron paramagnetic resonance spectroscopy; extraction; food analysis; food control; food dosimetry; Food industries; food irradiation; fresh fruit; fresh products; Fruit and vegetable industries; fruit pulp; Fundamental and applied biological sciences. Psychology; identification; kiwifruit; pawpaws; tomatoes; Kiwi(fruit); Fruit; Papaya; EPR spectrometry; Fruit vegetable; Solvent extraction; Tomato; Free radical; Ionizing irradiation; Gamma irradiation; Tropical fruit; Food preservation; Fruit pulp; Dosimetry
• ISSN: 0950-5423; 1365-2621
• DOI: 10.1046/j.1365-2621.1999.00250.x

In this work we use paramagnetic defects induced by radiation in the fruit pulp to identify gamma-irradiated kiwi, papaya and tomato. Pulp without seed, peels or stalks are treated by alcoholic extraction in order to remove water, soluble fractions and solid residue. The ESR spectra of pulp samples of irradiated fruit is composed of species A (g = 2.0045) and species C (g = 2.0201 and g = 1.9851), which are also observed in irradiated stalks and skins. In comparison with samples which are not submitted to alcoholic extraction, species C is stable enough to be used as a dose marker. Furthermore, the species C signal can be detected perfectly even in pulp samples irradiated with doses as low as 200 Gy. Irradiation doses of fruit, exposed to 200-900 Gy of a gamma rays, were estimated with an overall uncertainty of 15% using dried pulp samples. These results indicate that radicals induced in pulp have potential to be used in the identification and absorbed dose determination of irradiated fruit.