Oral communication in Workshop PICATA-CEI Campus Moncloa

February 12^nd, 2013

Navarro Y., Romero B., Palacios J., Herranz M., Bouza E., Dominguez L., de Juan L. and Garcia de Viedma D.

production, off-flavours and bad odors (Deák, 2008). Weak acids as sorbic acid and derived salts (sorbates) are common preservatives added to foods. There are resistant microorganisms that can metabolize such preservatives, transforming them into non-toxic molecules with spoiling properties. Our group was the first to describe the production of 1-3 pentadiene from sorbate by yeasts (Casas et al.1999, 2004). This metabolite has an unpleasant petroleum odour and has been detected in marzipan and nuggat. Therefore, a predictive model of risk spoilage that would linke yeast contamination and 1-3 pentadiene production would be of great use. Up
to date, predictive growth models have been made mainly in liquid media whereas most of food shows some degree of structure. In solid food yeasts can grow as surface colonies, whose behaviour can not be predicted accurately by the available models (Theys et al. 2010). To solve this problem a collaboration has been established between the LPF_TAGRALIA (UPM) and HOLEIAL (UCM). LPF_TAGRALIA is credited by works on data modeling derived from instrumented quality such as gas sensors, electronic noses and sensor networks. HOLEIAL is a recognized expert on yeast and filamentous fungi. Together we propose to develop complementary approaches to produce predictive models of risk spoilage. The specific objectives of this study are:
- Screening and selection of strains 1-3 pentadiene producers. Physiological studies of 1-3 pentadiene production (UCM)
- Development of methods to measure growth of yeast, including image analysis algorithms to automate measurements of growth in the different structures, with classical invasive and non-destructive, noninvasive, techniques. Development of predictive kinetic models of
growth and physiological models linking growth and spoilage metabolite production in different structures. Validation in artificially contaminated food. (UCM-UPM)
- Development of an economic sensor for detecting and quantifying 1-3 pentadiene. (UPM)

	Servicio de Micobacterias (MYC). Centro de Vigilancia Sanitaria Veterinaria (VISAVET). Universidad Complutense (UCM).
	Departamento de Sanidad Animal. Facultad de Veterinaria. Universidad Complutense (UCM).