Morphological Traits, Kernel Composition and Sensory Evaluation of Hazelnut (Corylus avellana L.) Cultivars Grown in Poland

In the present study, the nut and kernel traits of six hazelnut cultivars ('Barceloski', 'Kataloski', 'Webba Cenny', 'Olbrzym z Halle', 'Cosford', and 'Nottinghamski') grown in Poland were investigated. Results showed that significant differences estimated among all six cultivars with all selected morphological traits and compositional properties. During statistical analysis the year of the study was not found to affect most of the investigated traits. The investigated cultivars showed a lower protein content (11.27-13.44%), higher carbohydrate content (16.40-21.79%) and similar fat content (58.91-63.83%) to nuts grown in a warmer climate like Turkey, Italy or Spain. The studied hazelnut varieties were large-sized with diameters greater than 20 mm. The nuts of the 'Barceloski', 'Kataloski' and 'Olbrzym z Halle' cultivars were characterized by the smallest diameters of nut and kernel, were the most spherical (0.85-0.95) and exhibited the largest average nut volume (4.26-4.46). Significant differences were found between the cultivars for oil content and the ratios of major fatty acids. The QDA results, estimated that other than shape, the evaluated nuts significantly differed only in the intensity of nutty flavor (4.88-5.92). The highest intensity of this attribute was found in three cultivars, 'Nottinghamski', 'Cosford', 'Olbrzym z Halle', whereas the lowest estimate was found in the 'Barceloski' cultivar, which was also slightly less sweet and more bitter. As a result, the present study showed that the investigated hazelnut kernels can be divided into two groups: 'Nottinghamski', 'Cosford', and 'Webba Cenny' are suitable for table consumption, while 'Barceloski', 'Kataloski', and 'Olbrzym z Halle' are suitable for the processing industry. The current experimental results may help to growers and breeders when choosing the cultivars for new plantations and possibilities of destinations of the produced nuts, for confectionery use or table consumption.