1. 1Instituto de Ciencia y Tecnología de Alimentos y Nutrición, Instituto del Frío, Consejo Superior de Investigaciones Científicas, C/José Antonio Novais 10, E-28040 Madrid, Spain
2. 2Department of Cellular Biology, Faculty of Biology, Complutense University of Madrid, C/José Antonio Novais 2, E-28040 Madrid, Spain
3. 3Microscopy and Cytometry Research Centre, Complutense University of Madrid, E-28040 Madrid, Spain
4. 4Technical Unit of Mercamadrid, Public Health Institute, Madrid City Council, Mercamadrid, E-28053 Madrid, Spain