2-D Electrophoresis and Western Blot Analysis to Characterize and Trace Proteins in Industrial Lupin-Based Pasta Products

In this work, 2-D electrophoresis has been used to monitor the main steps of lupin-based gluten-free pasta production. Three different production lots, spanning over one year of pasta production, were analysed. Various samples at each critical production step, including seeds, raw materials, half-processed products and dry pasta, were used to generate the corresponding 2-D electrophoretic maps. All the 2-D maps have been digitalized and compared one to each other using a dedicated software. By and large, the results showed that technological processing did not alter the covalent continuity of the main polypeptides. Small differences between the raw materials, i.e. lupin flour and lupin protein concentrate, were attributed to the different varieties which they arose from. Protein glycosylation has also been assayed by using lectin reactivity in a Western blot analysis. The constancy of the glycosylation pattern of the analysed samples indicates that this feature was not affected by the treatment too. In conclusion, the work shows how helpful the use of 2-D electrophoresis for protein traceability and to evaluate the effects of the production processes in protein food manufacturing can be