Terres Inovia at the Euro Fed Lipid Congress in Poland
Terres Inovia at the Euro Fed Lipid Congress in Poland
Poznan, Poland. Monday 18th September. Florian Rousseau from Terres Inovia's Seed Processing Department (Pessac, 33) presented the results of his thesis on the mechanical extraction of sunflower kernels at the Euro Fed Lipid Congress.
The 19th Euro Fed Lipid congress was held from 17 to 20 September in Poznan, Poland. "Academics and companies came together to share their progress on the various lipid-related themes. Nutrition, analysis..." introduces Florian Rousseau, a doctoral student in the Seed Processing and Development Department at Terres Inovia (Pessac, 33). And in the case of Terres Inovia, it was the 'process' theme. I presented our advances in understanding the phenomena that come into play during mechanical extraction, and in particular in relation to the extrusion of shelled sunflower."
The phenomenon of cake extrusion linked to the speed of compression
The main discovery of this work is the demonstration of a cake extrusion phenomenon linked to the speed of compression. The faster we try to press, the lower the pressure at which the solid extrudes through the press orifices.
The phenomenon of extrusion had already been observed by other researchers, but never linked to the speed of compression. This observation suggests a hypothesis to explain why the cake extrudes in certain circumstances.
Extrusion could be the result of oil percolation being blocked. With unhulled seeds, the reduction in volume imposed by the movement of the piston pushes the oil out of the press until the mechanical strength of the cake equals the power of the piston.
In the case of low-shell matrices such as sunflower kernels, when the compression speed imposes an oil flow rate greater than that permitted by the permeability of the material, the pressure increases rapidly, leading to the collapse of the capillary networks through which the oil can flow.
When solid/liquid separation is no longer possible, the cake no longer behaves as a solid but as a viscous liquid capable of passing through the press orifices. Thanks to the solidity of the woody tissues of which they are made, the shells play a role in preserving capillaries in situations where they are in contact with water.
Contacts : Patrick Carré, p.carre@terresinovia.fr and Florian Rousseau, f.rousseau@terresinovia.fr