Abstract
The microbial formation of trimethylamine (TMA) can be used as a quality indicator compound to predict the
freshness of fish during its shelf life. In a supply chain with fluctuating temperatures, mathematical models
will be valuable tools to simulate this formation as a function of temperature and time. Thesemodels are essential
to link sensor data on the formation of TMA to the actual freshness of fish. Existing models for the formation of
TMA in fish needed improvements and secondary models for the effect of temperature on the formation of
TMA are lacking in the literature. Three different approaches were evaluated on their ability to simulate the experimental
observed TMA formation at 4 different temperatures (0, 5, 10 and 15 °C). In the first approach the
existing models were improved and the temperature effect was modelled by an empirical model using four parameters.
This model is able to simulate the TMA formation at static temperatures. Since TMA is produced on
fresh cod fillets by the micro-organisms Shewanella putrefaciens and Photobacterium phosphoreum the microbial
Baranyi–Roberts model was initially used for modelling the TMA formation, but this model was found to be too
complex (too many correlated parameters that could not be estimated). In the third approach it was seen that a
simplified Baranyi–Roberts model with only three parameters could be used to predict the TMA formation with
equal accuracy. The influence of the temperature on the parameter µmax was modelled using the extended square
rootmodel of Ratkowsky and the differences inTMA formation profiles of different batches could be described by
the batch specific parameter N0 representing the initial quality. The presented dynamic model is valuable in
predicting the formation of TMA in a fresh fish supply chain with dynamic temperatures. This model has the
potential to be used to link sensor data of TMA in the headspace to the actual freshness status of the fish.
Original language | English |
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Pages (from-to) | 272-278 |
Journal | Food Research International |
Volume | 56 |
DOIs | |
Publication status | Published - 2014 |
Keywords
- spoilage bacteria
- growth
- freshness
- food