Fruit chemical composition of hazelnut cultivars grown in Portugal

Abstract: Chemical composition (crude protein, crude fat, starch, neutral detergent fibre - NDF and free a-amino acids) of six hazelnut cultivars (Butler, Ennis, Fertile de Coutard, Grossal, Merveille de Bollwiller and Segorbe) was investigated. Genotype significantly affected fruit nutritive value. Crude protein ranged from 12-17 g 100 g^-1 dry weight (dw) in cultivar Ennis and Merveille de Bollwiller, respectively; crude fat was 50-62 g 100 g^-1 dw in cvs. Fertile de Coutard and Butler; starch varied from 1.0 to 2.4 g 100 g^-1 dw in cvs. Segorbe and Butler; and NDF was 8-14 g 100 g^-1 dw in cvs. Merveille de Bollwiller and Ennis. Total free a-amino acids content ranged from 144 mg 100 g^-1 dw (cv. Segorbe) to 413 mg 100 g^-1 dw (cv. Butler). The essential amino acids content varied between 23 mg 100 g^-1 dw (cv. Butler) to 55 mg 100 g^-1 dw (cv. Merveille de Bollwiller). Alanine was the main amino acid found (62% of total amino acids) and methionine was the lowest (0.3%). Based on the available data on the phytochemical content of hazelnuts, including the data presented in this study, there is a high likelihood that this fruit will provide positive health benefits.