Effect of die material on engineering properties of dried pasta

• Published in: Procedia food science Vol. 1; pp. 557 - 562
• Main Authors: Mercier, Samuel, Marchais, Louis-Philippe Des, Villeneuvea, Sébastien, Foisy, Mathieu
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 2011
• Subjects: bronze die; effective moisture diffusivity; engineering properties; Pasta drying; porosity; shrinkage; Pasta drying; effective moisture diffusivity; engineering properties; shrinkage; porosity; bronze die
• ISSN: 2211-601X; 2211-601X
• DOI: 10.1016/j.profoo.2011.09.084

Extruding wheat semolina dough through a Teflon die allows to process pasta with a smooth and even surface, whereas bronze die can be used to obtain a product with a rough texture. Little is known about the impact of the die material on pasta properties other than surface characteristics. Knowledge of pasta properties would be relevant to better understand pasta digestibility. The aim of this work was to analyse the impact of the die material on engineering properties of dried pasta. Pasta were processed with fine semolina using a pasta extruder equipped with a 2.5mm Teflon or bronze die. They were dried inside an environmental chamber under a controlled atmosphere at 40°C or 80°C for 20hours. Pasta shrinkage, porosity and effective moisture diffusivity were measured. Scanning electron microscopy (SEM) was performed to characterize the external structure of pasta. Results showed that extrusion with a bronze die induces the production of more porous and less dense pasta, but does not have an impact on pasta shrinkage and volumetric percentage of water lost replaced by air during drying. Effective moisture diffusivity coefficients were higher for pasta extruded with a bronze die compared to a Teflon die for both drying temperatures studied, which indicates that the use of a bronze die could induce a diminution of the drying time. SEM observations at 50X and 500X clearly showed that pasta microstructure was affected by processing conditions. These results highlight the importance of food processing and their impact on the microstructure and characteristics of food matrices. Since pasta can be regarded as a good matrix for the incorporation of bioactive compounds beneficial to health and well-being, further studies are needed to better understand how processing would affect pasta digestibility and the release of bioactive compounds in terms of bioaccessibility into the gastro-intestinal tract.