Enzymatic activities in the varieties of hazelnuts (Corylus avellana L.) grown in Tarragona, Spain

Enzymatic activities of lipase, esterase, lipoxygenase (LOX), peroxidase (POD) and polyphenoloxidase (PPO) of the main local, Italian and Turkish varieties of hazelnuts grown in Tarragona, with and without irrigation, were determined. Enzymatic extract protein was estimated by calculating Δ Abs/min.mg of protein with spectrophotometry. Oleic (C18:1) and linoleic (C18:2) acid percentages were determined using high resolution gas chromatography (HRGC). Data were statistically analysed using General Linear Models and Duncanʹs multiple test. It is observed that variety is a determining factor for all enzymatic activities, especially lipase and peroxidase activity. Negret (Negret and Pauetet varieties), the most cultivated variety in Tarragona, has a high C18.2 content and high enzymatic activities. Italian varieties have lower lipase, POD and PPO activities. All varieties show minimum activity of esterase and lipoxygenase.