Interactions between Maillard Reaction Products and Lipid Oxidation During the Roasting Process and Storage of Hazel-Nuts (Corylus avellana)

Abstract

Raw hazel-nuts and the oil extracted from the raw nuts were heat treated at 150°C in a laboratory scale plant to simulate a roasting process. Measurements of colour and HMF content were performed to evaluate the non enzymatic browning. On the treated oil and on the oil extracted from the roasted nuts, determinations of lipid oxidation using chemical and instrumental methods were carried out to establish the antioxidative effect of the Maillard reaction products (MRP) formed during the thermal process. After roasting, the granulated hazel-nuts and the extracted oil were stored at 50°C to follow the development of lipid oxidation. Results obtained in preliminary trials show how the lipid oxidation of the oil in the nuts was reduced in comparison to oxidation in raw nut oil subjected to the same heat treatment.