Analysis of organic acids in electron beam irradiated chestnuts (Castanea sativa Mill.): Effects of radiation dose and storage time

Abstract

Since 2010, methyl bromide, a widely used fumigant was banned from the European Union under the Montreal Protocol guidelines, due to its deleterious effects on health and risk to the environment. Since then, many alternatives for chestnut conservation have been studied (hot water dip treatment being the most common), among them, electron beam irradiation has been proposed as being a safe, clean and cheap alternative.Herein, the effects of this radiation at different doses up to 6 kGy and over storage up to 60 days in the amounts and profile of nutritionally important organic acids were evaluated. Chestnuts contained important organic acids with quinic and citric acids as main compounds. Storage time, which is traditionally well accepted by consumers, caused a slight decrease on quinic (13 to 9 mg/g), ascorbic (1.2 to 0.8 mg/g), malic (5 to 4 mg/g), fumaric (0.4 to 0.3 mg/g) and total organic (33 to 26 mg/g) acids content.Otherwise, irradiation dose did not cause appreciable changes, either individually or in total (28 to 27 mg/g) organic acid contents. Electron beam irradiation might constitute a valuable alternative for chestnut conservation.

Effect of Extraction and Processing Conditions on Organic Acids of Barberry Fruits

“…Thus, irradiation does not cause great changes in the total or individual content of organic acids (Carocho et al . ). Other researchers have reported that irradiation increased the quinic acid content (Kim and Yook ).…”

Comparison of different drying methods on the chemical and sensory properties of chestnut (Castanea sativa M.) slices

“…The organic acids extraction was performed according to the method described by Carocho et al [20] with some modifications, namely the addition of internal standard and the application of a sequential extraction. In more detail, samples (500 mg, in duplicate) were mixed with 5 mL of meta-phosphoric acid (3%, w/v) and 150 µL of gallic acid, as internal standard (1 mg/mL), for 30 min in a vortex.…”

Organic acid profile of chestnut (Castanea sativa Mill.) as affected by hot air convective drying

“…The organic acid extraction was performed with meta-phosphoric acid (3%, w/v), according to the method described by Carocho et al [27] , with some modifications in what regards the addition of an internal standard and the application of a sequential extraction. In more detail, samples (500 mg, in duplicate) were mixed with 150 µL of gallic acid solution (1 mg mL…”