IGEM:IMPERIAL/2007/Cell By Date/Modelling

= Cell by Date =



Introduction Specifications Design Modelling Fabrication Testing DataAnalysis Validation Notes</li> References</li> </ul> <br style="clear:both">

Modelling the spoilage of Aerobically Stored Ground Hamburger Meat


Previous work has been carried out to model the spoilage of ground beef by living organisms. Above in figure 1 is is a model developed by Koutsoumanis in 2006 which colesly fit the behaviour of the spoilge organism we are interested in, Pseudomonas, under dynamic temperature conditions. One of the Key conclusions drawn from this model is the almost instantaneous repsone time of the Pseudomonas' growth parameter. The result of this is that our system needs to have a quick respone time to correclty report the temperature history of the beef.

Koutsoumanis' and also one Giannuzzi developed in 1998 are both based on the Gompertz model. This model allows some insight into the mechanisms of ground beef spoilage. In particular through manipulation of the Gompertz Parameters and assuming a Arrhenius type relationship between Pseudomonas' growth parameter and temperature we can infer the Activation energy of the spoilage reaction. This is shown in figure 2 in which a stongly linear behaviour allows us to continue with our Arrhenius assumption and extract that Activatoin energy of the spoilge reaction. As given in our specifications the Activation energy for ground meat seem to be around 30kJ/mol. The result of this as per Taoukis' work is that our system needs to have a similar activation energy. I hope to determine our system activation energy in the same way Giannuzzi determined Pseudomonas'.