Pomological traits and proximate chemical composition of Hazelnut (Corylus avellana L.) varieties grown in Croatia

The aim of this research was to determine the pomological traits and proximate chemical composition of economically important Hazelnut (Corylus avellana L.) varieties grown in Croatia. Autochthonous variety Istarski duguljasti is the most represented variety in production, followed by introduced varieties Romische Zellernuss and Hallesche Riesen. Research was conducted during four vegetation seasons. Pomological traits (productivity/yield, number of fruits, nut weight, kernel weight, percent kernel) and proximate chemical composition of hazelnuts (fats, carbohydrates, proteins, ash and moisture) were determined. During the period of research, Romische Zellernuss variety had the highest yield; Hallesche Riesen variety had approximately the similar yield, while Istarski duguljasti had the lowest. However, Istarski duguljasti variety demonstrated stability and regular fertility during all years of research. Proximate chemical composition (of fresh material) varied per variety and per year. Fats were predominant compound which content ranged from 61.60 - 67.59 g/100 g, followed by carbohydrates (15.75 - 20.58 g/100 g) and proteins (10.16 - 13.13 g/100 g). Ash content in hazelnut kernel ranged from 2.51 - 2.85 g/100 g, and moisture content from 2.87 - 3.21 g/100 g. Results obtained in research suggest that external and internal parameters of hazelnut quality are influenced by variety, harvest year and their mutual interactions.