Postharvest Biology and Technology 81 (2013) 1–6 Contents lists available at SciVerse ScienceDirect Postharvest Biology and Technology jou rnal h omepa g e: www.elsevier.com/locate/postharvbio Effects of gamma and electron beam irradiations on the triacylglycerol proﬁle of fresh and stored Castanea sativa Miller samples João C.M. Barreira a,b , Márcio Carocho a , Isabel C.F.R. Ferreira a,∗ , Amilcar L. Antonio a,c,d , Iwona Kaluska e , M. Luisa Botelho c , Albino Bento a , M. Beatriz P.P. Oliveira b a CIMO/Escola Superior Agrária, Instituto Politécnico de Braganc ¸ a, Apartado 1172, 5301-855 Braganc ¸ a, Portugal b REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia da Universidade do Porto, Rua Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal c IST/ITN, Instituto Tecnológico e Nuclear, Estrada Nacional 10, 2686-953 Sacavém, Portugal d Departamento de Física Fundamental, Universidade de Salamanca, Plaza de la Merced, 37008 Salamanca, Spain e Centre for Rad. Research and Techn., Inst. of Nuclear Chem. and Technology, Dorodna str. 16, 03-195 Warsaw, Poland a r t i c l e i n f o Article history: Received 3 January 2013 Accepted 12 February 2013 Keywords: Chestnut Electron beam irradiation Gamma irradiation Triacylglycerols Linear discriminant analysis a b s t r a c t The present chestnut (Castanea sativa Miller) commercialization process, including distribution to novel markets, demands suitable preservation technologies. Irradiation has been considered a promising alter- native to chemical fumigation (legally forbidden and harmful for human health and environment) or heat treatments (technological difﬁculties and low efﬁciency). Following previous studies on the effects of irradiation in different chemical parameters, the present work aimed to evaluate the effects of elec- tron beam and -irradiation on the triacylglycerol proﬁles of fresh and stored chestnuts. An analysis of variance with type III sums of squares was performed using the general linear model procedure. As a classiﬁcation technique, a linear discriminant analysis using the stepwise procedure was also applied. Independently of irradiation type, samples irradiated with higher doses showed higher modiﬁcations in triacylglycerol proﬁles. Samples irradiated with 1 and 3 kGy were clearly separated from the remaining groups in the linear discriminant analysis. The results highlight the potential of triacylglycerol proﬁles as indicators of chestnut irradiation. Irradiation might be recommended as a suitable method for chestnut preservation. © 2013 Elsevier B.V. All rights reserved. 1. Introduction Chestnut quality is measured by external factors such as color, shape, size, surface blemishes and molds, which are very impor- tant for consumer acceptance. Internal disorders may result from anatomical or physiological changes such as moisture loss, chem- ical conversion, discoloration, senescence, microorganism attack, cell breakdown (physiological decay) and insect injury (Upchurch et al., 1993). Weight losses due to dehydration and infestation by insects and microorganisms are the two main problems in chestnut preservation, and neither chemical fumigants, nor heat treatments, represent an effective solution (Pinto et al., 2007). Furthermore, chemical fumigation is harmful to human health and to the environment (UNEP, 2006), while heat treatments do not prevent mold growth (Jermini et al., 2006). Quality require- ments demand enhanced preservation techniques for chestnuts and related products. In this context, decontamination methods based on high-energy electrons or -ray irradiation are being ∗ Corresponding author. Tel.: +351 273303219; fax: +351 273325405. E-mail address: iferreira@ipb.pt (I.C.F.R. Ferreira). studied as alternatives. Arici et al. (2007) irradiated black cumin with 2.5–10 kGy for the purpose of microorganism elimination, while studying the effects on physico-chemical properties and on fatty acids proﬁles. Beneﬁcial effects of irradiation include reduction of storage loss, shelf-life extension, and improvement of microbiological and parasitological safety of foods, while being safe to the environment. Hence, irradiation might be considered a promising preservation technology, bearing in mind that the doses applied on fresh fruit and processed fruit products are limited by the impact on their quality (Arvanitoyannis et al., 2009). Particu- larly, gamma-irradiation has already been applied to diverse food products such as tuber and bulb crops, stored grains, dried ingredi- ents, meat, poultry and ﬁsh, and fruit (Farkas, 2006). It can also be applied to chestnuts which contain only 1% of fat, overcoming the production of off-odor compounds due to the radiation-induced breakdown of lipids common in high-fat-containing foods (Niyas et al., 2003). Electron beam irradiation is also widely applied to improve food quality and safety. The use of electron accelerators as source of radiation has technological advantages such as higher throughput, wider ﬂexibility and more potential to overcome public objections to radioactive isotopic sources (Supriya et al., 2012). Nevertheless, 0925-5214/$ – see front matter © 2013 Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.postharvbio.2013.02.005