Evaluation of gels made with different commercial pea protein isolate: Rheological, structural and functional properties

The gelling of two commercial pea protein isolates (PPI) at 20% and 23% PPI concentration, and the effect of microbial transglutaminase (-0- and -5- U/g protein), were analysed. The final aim was to get PPI gels with textural properties enough to make meat and seafood analogues. The first PPI (-A-), was made by alkaline solubilization and isoelectric precipitation from pea flour. The second one (-B-), was obtained by aqueous dispersion of the pea flour and concentration of the soluble protein. The water and oil holding capacities of PPI-A suggested a higher degree of protein denaturation which was assessed by Dynamic thermo mechanical analysis (DMTA) and Fourier transform infrared spectroscopy (FTIR). FTIR data showed lower intermolecular β-sheet aggregates in PPI-B gels than in PPI-A. This result was consistent with the reticulated and well-interconnected network from scanning electron microscopy (SEM) of PPI-B gels in line with the higher strain amplitude (γmax), and the lower loss factor (tanδ) in PPI-B gels vs PPI-A gels. The MTGase enzyme significantly improved the structural quality of the PPI-B gels (high Q-factor) at 20% and 23% PPI. For all these reasons PPI B is more suitable for achieving consistent gels as bases for meat and seafood analogues.Depto. de Producción AnimalFac. de VeterinariaTRUEpu

Linseed, microalgae or fish oil dietary supplementation affects performance and quality characteristics of light lambs

<p>The aim of this work was to improve the fatty acid profile of meat from light lamb, frequently reared in Spain and in other Mediterranean countries. A total of 44 light lambs fed different n-3 polyunsaturated fatty acids sources were studied: control (C) (palm oil), extruded linseed (L), extruded linseed mixed with microalgae (LM) and fish oil (FO). The productive performance from 14.7 to 26.2 kg of live weights and meat quality characteristics during refrigerated storage were assessed. Lambs fed FO showed lower feed intake (<em>p</em> &lt;0.001), average daily gain (<em>p</em> &lt;0.001) and higher feed conversion ratio (<em>p</em> &lt;0.001) than lambs from the other treatments. Fish oil meat had the lowest (<em>p</em> &lt;0.01) protein proportion and the highest (<em>p</em> &lt;0.001) C20:5n-3, C22:5n-3 and C22:6n-3 proportions, while L or LM produced the highest (<em>p</em> &lt;0.001) C18:3n-3 deposition. Fish oil meat had higher (<em>p</em> &lt;0.05) L* and lower (<em>p</em> &lt;0.001) a* than meats from the other treatments. After 7 days of storage, FO meat showed the highest TBARS (<em>p</em> &lt;0.001), while C meat showed similar value to 0 days of storage. Additionally, FO underwent higher microbial growth after 7 days of storage as compared to the other treatments. Dietary supplementation with L and LM leads to C18:3n-3 meat enrichment and to a microbial load and colour characteristics similar to those of C, without adverse effect on lamb performance. However the use of FO improves the fatty acid profile of meat, but negatively affects lamb performance and meat quality.</p