Study of the carbohydrate fraction of the principal varieties of Tarragona hazelnuts (Corylus avellana L.)

Abstract The amounts of sugars, starch and fibre were determined in 22 samples of the main varieties of Tarragona hazelnuts (Negret, Pauetet, Gironell, Culpla, Morell and Grifoll). The main sugar identified by gas chromatography was sucrose, with small amounts of glucose, fructose, myo-inositol and raffinose. The typical mountain varieties (Culpla and Morell) showed the highest sucrose contents (7.90 g/100 g and 6.80 g/100 g of defatted material, d.m.). The amount of reducing sugars exceeded 0.40 g/100 g d.m. in only one sample. All varieties had similar contents of starch, neutral detergent fibre (NDF) and acid detergent fibre (ADF).