Effect of roasting on some nutrients of hazelnuts (Corylus Avellena L.)

Changes in total amino acid composition, thiamine and riboflavin contents, peroxide value and free fatty acid contents were determined in roasted Giresun and Akçakoca hazelnuts. The results showed that roasting significantly affected peroxide value, free fatty acids, thiamine, riboflavine and total amino acid composition of Akçakoca and Giresun hazelnuts. Riboflavin level decreased by almost 30% in Akçakoca hazelnuts and 18% in Giresun hazelnuts. Above 120°C, more than 50% of thiamine was lost. Amino acid levels in Akçakoca and Giresun hazelnuts generally decreased as the roasting temperature increased. Lysine diminished <6% in samples of roasted Giresun hazelnuts. In Akçakoca hazelnuts, a higher lysine loss was observed (31%) in the sample roasted at 126°C for 45 min.