GroPIN Modelling DataBase

Laboratory of Food Quality Control & Hygiene

Department of Food Science and Technology

Agricultural University of Athens

Developers:

Dr. Antonios N. Psomas (apsomas@aua.gr, APsomas@reamaternity.gr)

Prof. Panagiotis N. Skandamis (pskan@aua.gr; pskan@otenet.gr)

Fig.1. Flowchart representing the outcome of the GroPIN software

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

GroPIN tertiary model constitutes a standalone application, developed in VBA (Visual Basic for Application). The software is using Microsoft Excel 2007-2010 as a platform for the data introduction and processing.

The Microsoft Excel database is supported by a servicing application which has been designed especially for scientific and industrial use.

Solver add-in software (Frontline Systems) has been harmoniously integrated into the source code in order to provide solution for the growth-no growth calculations.

 

 

Zip file includes:

1. GroPIN.xlsm (GroPIN software)

2. Dynamic Files Folder, including examples of files with dynamic conditions

3. Documentation.pdf

 

DOWNLOAD INSTRUCTIONS

In order to execute GroPIN software, the following software has to be installed into your computer:

1. Microsoft Office 2007 or 2010

2. The corresponding Solver, Excel Add-In application

 

Design and Development of an Integrated Food Microbial Tertiary Model

An integrated tertiary model called GroPIN is developed in-house using Visual Basic for Applications. The application may serve as a user-friendly and highly transparent predictive modeling data base for kinetic (growth or inactivation) and probabilistic models. It also offers the flexibility of interactive options in selecting the graphical and numerical simulation of models. An unlimited number of mathematical models can be introduced into the database via equation editor, as compared with other applications, where only a limited number of equations are already embedded into the source code and are not (at least not easily) updatable or expandable.

The current version of GroPIN has a total of 367 published models for the behavior of 29 pathogens and 43 spoilage organisms, including spoilage and mycotoxigenic fungi, bacteria and yeasts in various foods of plant (e.g., fresh-cut salads, deli salads, berries, juices, etc.) or animal origin (meat and meat products, dairy products). The impact on microbial behavior of a variety of critical and commonly encountered intrinsic (preservatives, organic acids in total or undissociate/dissociate form, salt, aw, nitrates, etc.) and extrinsic (temperature, CO2, pressure, anaerobic conditions) factors is accounted for by the models registered in GroPIN up to date. The microbial responses modeled (i.e., dependent variables) include the maximum specific growth rate, the death rate, the lag phase duration, maximum population density, time to X-log reduction/growth, D-values and the probability of growth.

A search engine has been established for locating and selecting the model of interest. Then the user may select variables and assign values for each variable though list boxes or by direct typing. The simulation of the selected model can be displayed as Response Surface-Contour Plot, Time to x log Response Surface-Contour Plot, growth or inactivation curve, as well as 2D growth/no growth (probabilistic) interface with potential illustration of up to 3 interfaces (i.e., three levels of the 3rd variable). The following model categories have been included: (1) Probabilistic models; (2) Growth models; (3) Inactivation-survival models, and; (4) Gamma (Cardinal) Models with interactions (x term based on y and j functions, according to Augustin and Carlier., 2000; Le Marc et al. 2002). All kinetic models, including growth or inactivation, plus gamma models with interactions, can be simulated under both static and dynamic conditions. The 367 registered models include 246 growth models, 46 inactivation models, 64 probability of growth models and 11 gamma models with interaction terms. The user can use the available models as a basis for setting performance-, process- or product-criteria, as well as to evaluate the compliance of a product with microbiological criteria regulation. The integrated models constitute a special category which combines selected models from a series of 26 growth models, 14 inactivation models and 32 probability of growth models under dynamic conditions. The final graphical representation is the integral of the selected models. Moreover, a series of computational algorithms that rely on repeated random sampling have been applied in order to estimate the risk in food products (Monte Carlo simulation).

The spirit of the software stems from similar initiatives, such as SymPrevius and COMBASE modeling toolbox. The major innovative features of this software in relation to the state-of-the art are the user-friendliness, the updatable character by the user, the simplicity and functionality (including interactive options) of outputs and the inclusion of all major predictive modeling classes.

GroPIN software is being continuously updated. Please check for newer release on webpage. When a new update is available, please replace the older version on your disk by the newly downloaded file.

 

New software update: 06/09/2014

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The updated version includes a novel addition on the comparison of two different microorganism-food systems under the same conditions or even the comparison between the different conditions of the same microorganism-food system. The user may find information in detail into the USERs GUIDE, which can be downloaded from the dissemination webpage.

 

 

 

 

 

 

 

 

 

 

Comparison between 2 microorganism-food systems

Comparison between 2 different conditions of the same food system