Descrição
Chestnut fruits are an important food commodity in the Northeast region of "Trás-osMontes",
representing an income of approximately 17 M€ and being Porn1gal one of the:
world's biggest producer. Due to environmental concerns a broad spectrum fumigant,
methyl bromide, was banned in 20 I 0 by the European Union. Since then, no adequate
postharvest treatment has been implemented, fostering research on suitable alteratives.
Our research group has been testing gamma and electron beam irradiation as an alternative
postharvest treatment for chestnuts. On a first attempt to evaluate the influence of
irradiation, various doses were tested (0, 0.5, I, 3 and 6 kGy) along different storage times
(0, 30 and 60 days). The effects were assessed in the most important chemical parameters,
namely nutritional, antioxidant, sugar, fatty acid, tocopherol, organic acid and
triacylglyccrol profiles, in which, all seemed to be altered to a greater extent by storage
time than by the different doses. Another important conclusion was the validation of I kGy
as the optimal dose for chestnuts conservation. This conclusion sustained the venture to
extend the study to four varieties (Longal, Judia, Cotaand Palummina) with a fixed dose of
I kGy for both gamma radiation and electron beam. The results were processed through
principal component analysis and confined that both gamma (1) and electron beam (2)
irradiation showed high potential to be used as postharvest conservation technology. The
most marked differences were found between the four different cultivars, especially Cola
and Palummina, while non-irradiated and irradiated chestnuts proved to have very similar
profiles in all the assayed parameters, with irradiation having an attenuating effect.
; Antonio, Amilcar L. 
