Growth Predictor
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Welcome to Growth Predictor
A predictive modelling and QMRA software based on gamma concept models
Developer: Prof. Panos N. Skandamis
Agricultural University of Athens,pskan@aua.gr
Intr/Extrinsic factors
Cardinal values
Module
Import data (XL) file
Browse...
Static vs Dynamic conditions
Isothermal
Dynamic t-T
1
File with 2 columns: time, T
Import time-T (XL) profile
Browse...
Interpolation step
Storage temperature
Storage time (days)
Initial level (Log CFU/g or ml)
Maximum population density (Log CFU/g or ml)
Work-To-Be-Done (ho: 0.1 to infinity)
sd ho (stochastic lag)
Deterministic vs stochastic growth limits
Fixed value
Normal dist.
Pick from dbase
Tmin
Average Tmin
SD Tmin
pHmin
Average pHmin
SD pHmin
awmin
Average awmin
SD awmin
MIC of NO2- or any inhibitor
Exponent 1 of inhibitor term
Exponenet 2 of inhibior term
Average MIC of NO2- or inhibitor
SD MIC
Microorganism
Salmonella
STEC
Bacillus cereus
Non-prot Cl botulinum
Psychrot LAB
Pseudomonads
SD Tmin
SD pHmin
SD awmin
SD MIC
Tref (or Topt)
muref (or muopt) 1/h
Select modules
Growth
Growth & Inactivation
Dref (min)
Tref
Z
Heating Temp
Heating time (min)
Growth curves
Download
Product selection
Select product
All products
Pick up a product
Product
Product characteristics
Built-in dbase models
Intr/Extrinsic factors
Cardinal values
Module
Static vs Dynamic conditions
Isothermal
Dynamic t-T
Dynamic t-T/pH/aw
Time units
Days
Hours
1
File or Table with 2 columns: time, T
Select file or table input
File
Table
Import time-T (XL) profile
Browse...
Import
Iterations
2
File or Table with 4 columns: t/T-pH-aw
Select file or table input
File
Table
Import time-T/pH/aw (XL) profile
Browse...
Import
Iterations
SD of Temp. distr.
SD of Time distr.
SD of pH. distr.
SD of aw distr.
SD of Inhibitor1 distr.
Iterations
Storage T°C
Storage time (days)
Storage time (hours)
pH
aw
Nitrites (Inhibitor 1, ppm)
Add more inhibitors
%CO2 in pacakge headspace
Units
%
SD
Gas:product ratio
Value Inh.3
Units
ppm
%
SD
Value OA1
Units
ppm
%
SD
OA1 input represents Total Acid (HA)
Value OA2
Units
ppm
%
SD
OA2 input represents Total Acid (HA)
Value OA3
Units
ppm
%
SD
OA3 input represents Total Acid (HA)
Initial contamination (Log CFU/g or ml)
Maximum population density (Log CFU/g or ml)
Work-To-Be-Done (h0: 0.1 to infinity)
sd ho (stochastic lag)
user-defined or pick up from dbase
System values
Pick from dbase
Rosso model for T°C (n=2)
Rosso model for pH (n=1)
Rosso model for aw
pH12 model
pHref (when pH12 model is enabled)
Ignore pHref (consider muopt)
muFood correction Factor
n for aw
Including the xsi interaction term
Average muref(muopt)
SD muref(muopt)
Average Tmin
SD Tmin
Average Tref or Topt
SD Tref or Topt
Average Tmax (when Rosso model is enabled)
SD Tmax (when Rosso model is enabled)
Average pHmin
SD pHmin
Average pHopt (when Rosso model is enabled)
SD pHopt (when Rosso model is enabled)
Average pHmax (when Rosso model is enabled)
SD pHmax (when Rosso model is enabled)
Average pH12 (when pH12 model is enabled)
SD pH12 (when pH12 model is enabled)
Average awmin
SD awmin
Average awopt or awref
SD awopt or awref
Average awmax (when aw cardinal model is enabled)
SD awmax (when aw cardinal model is enabled)
Avrg MIC of Nitrites
Units
ppm
SD MIC
Exponent 1 of Nitrites
Exponent 2 of Nitrites
Microorganism
Salmonella
STEC
Bacillus cereus
Non-prot Cl botulinum
Psychrot LAB
Pseudomonads
Average muref(muopt)
SD muref(muopt)
Average Tref(Topt)
SD Tref(Topt)
SD Tmin
SD Tmax
SD pHmin
SD pHopt
SD pHmax
SD pH12
SD awmin
SD awopt
SD awmax
SD MIC
Add more inhibitors
MIC CO2 (Inhibitor 2)
Units
ppm
Exp. 1 of CO2 term
Exp. 2 of CO2 term
MIC Inhibitor 3
Type name of Inh. 3
Units
ppm
%
Exp. 1 of Inhibitor 3 term
Exp. 2 of Inhibitor 3 term
MIC Und.OA 1
Select organic salt
Na-Acetate
Na-Lactate
Na-Citrate
Na-Benzoate
K-Sorbate
Na-Diacetate
Ca-Propionate
Units
mM
Exp. 1 of Inhibitor 4 term
Exp. 2 of Inhibitor 4 term
Distribution of MIC of UOA1
Normal
Pert
SD of MIC
Min. MIC
Mode MIC
Max. MIC
MIC Und.OA 2
Select organic salt
Na-Acetate
Na-Lactate
Na-Citrate
Na-Benzoate
K-Sorbate
Na-Diacetate
Ca-Propionate
Units
mM
Exp. 1 of Inhibitor 5 term
Exp. 2 of Inhibitor 5 term
Distribution of MIC of UOA2
Normal
Pert
SD of MIC
Min. MIC
Mode MIC
Max. MIC
MIC Und.OA 3
Select organic salt
Na-Acetate
Na-Lactate
Na-Citrate
Na-Benzoate
K-Sorbate
Na-Diacetate
Ca-Propionate
Units
mM
Exp. 1 of Inhibitor 6 term
Exp. 2 of Inhibitor 6 term
Distribution of MIC of UOA3
Normal
Pert
SD of MIC
Min. MIC
Mode MIC
Max. MIC
Select modules
Growth
Growth & Inactivation
Dref (min)
Tref
Z
Heating Temp
Heating time (min)
Growth curves
Growth/No growth interface
Type of miro/sm
Bacteria/yeasts
Fungi
Show or hide (hold) real-time simulation results, for setting inputs first
Overlay graphs
Single graph
Select X and Y variable for G/NG interface (switch to system values)
ONLY for ISOTHERMAL conditions, same model as that for GROWTH
T(°C)
pH
aw
NO2-
CO2
Phenolics
LA or CA
AA or BA
SA or DAC
'PSI' criterion
Paste your own data here
Import data
Reset the curves
Download GNG interface
% -> ppm/10.000
Import/Export data
Independent data
Choose one of the following
Import data
Clear data
Import data
Browse...
Download Model Outputs
Built-in dbase models
Estimating time for certain log increase
Log increase
Reset numerical inputs / store-upload cardinal values
Reset ALL numeric Inputs of GP
Save your cardinal values
Save cardinal values as .CSV
Upload cardinal values
Browse...
Download XL Template (as in .zip user guide files)
Farm to end of processing
NO (initial contamination)
Fixed value
Normal
Pert
Discrete
Average
Average
SD
Minimum
Mode
Maximum
Import
Temperature distribution
Fixed value
Normal
Logistic
Gamma
Pert
Uniform
Discrete
Average
Average
SD
alpha
beta
alpha
beta
Minimum
Mode
Maximum
Minimum
Maximum
Import
Time distribution (days)
Fixed value
Normal
Exponential
Logistic
Gamma
Pert
Triangular
Average
Average
SD
lambda
max. time
alpha
beta
alpha
beta
Minimum
Mode
Maximum
Minimum
Mode
Maximum
Nmax (Log CFU/g or ml)
Fixed value
Normal
Uniform
Average
Average
SD
Min.
Max.
Growth estimation
With growth model
Fixed value
Log increase (only positive)
SD
Work-To-Be-Done (h0)
pH
pH distribution
Fixed value
Normal
Pert
SD of pH
Minimum
Mode
Maximum
aw
aw distribution
Fixed value
Normal
Pert
SD of aw
Minimum
Mode
Maximum
Inhibitor (%, ppm. mM...)
Inhibitor distribution
Fixed value
Normal
Pert
SD of inhibitor
Minimum
Mode
Maximum
Reduction by processing
Fixed value
Normal
Pert
Uniform
Average
Average
SD
Minimum
Mode
Maximum
Minimum
Maximum
End of processing to retail
Partitioning
No partition
Partition
Partition coefficient (>0-1)
Initial mass (g:0-infinity)
Mixing
Initial mass (g: 0-infinity)
Added mass (g: 0-infinity)
P cross-contamination (0-1)
Cross- (re-)contamination levels
Fixed value
Normal
Pert
Discrete
Average
Average
SD
Minimum
Mode
Maximum
Minimum
Mode
Maximum
Import
Temperature distribution
Fixed value
Normal
Logistic
Gamma
Pert
Uniform
Discrete
Dynamic profile
Average
Average
SD
alpha
beta
alpha
beta
Minimum
Mode
Maximum
Minimum
Maximum
Import
Download an XL Template
Import time-T (XL) profile
Browse...
Time distribution (days)
Fixed value
Normal
Exponential
Logistic
Gamma
Pert
Triangular
Average
Average
SD
lambda
max. time
alpha
beta
alpha
beta
Minimum
Mode
Maximum
Minimum
Mode
Maximum
Nmax (Log CFU/g or ml)
Fixed value
Normal
Uniform
Average
Average
SD
Min.
Max.
Growth estimation
With growth model
Fixed value
Log change (+x or -x)
SD
Work-To-Be-Done (h0)
pH
pH distribution
Fixed value
Normal
Pert
SD of pH
Minimum
Mode
Maximum
aw
aw distribution
Fixed value
Normal
Pert
SD of aw
Minimum
Mode
Maximum
Inhibitor (%, ppm. mM...)
Inhibitor distribution
Fixed value
Normal
Pert
SD of inhibitor
Minimum
Mode
Maximum
Retail
Partitioning
No partition
Partition
Partition coefficient (>0-1)
Initial mass (g:0-infinity)
Mixing
Initial mass (g: 0-infinity)
Added mass (g: 0-infinity)
P cross-contamination (0-1)
Cross- (re-)contamination levels
Fixed value
Normal
Pert
Discrete
Average
Average
SD
Minimum
Mode
Maximum
Import
Temperature distribution
Fixed value
Normal
Logistic
Gamma
Pert
Uniform
Discrete
Dynamic profile
Average
Average
SD
alpha
beta
alpha
beta
Minimum
Mode
Maximum
Minimum
Maximum
Import
Download an XL Template
Import time-T (XL) profile
Browse...
Time distribution (days)
Fixed value
Normal
Exponential
Logistic
Gamma
Pert
Triangular
Average
Average
SD
lambda
max. time
alpha
beta
alpha
beta
Minimum
Mode
Maximum
Minimum
Mode
Maximum
Nmax (Log CFU/g or ml)
Fixed value
Normal
Uniform
Average
Average
SD
Min.
Max.
Growth estimation
With growth model
Fixed value
Log change (+x or -x)
SD
Work-To-Be-Done (h0)
pH
pH distribution
Fixed value
Normal
Pert
SD of pH
Minimum
Mode
Maximum
aw
aw distribution
Fixed value
Normal
Pert
SD of aw
Minimum
Mode
Maximum
Inhibitor (%, ppm. mM...)
Inhibitor distribution
Fixed value
Normal
Pert
SD of inhibitor
Minimum
Mode
Maximum
Domestic environment
Partitioning
No partition
Partition
Partition coefficient (>0-1)
Initial mass (g:0-infinity)
Mixing
Initial mass (g: 0-infinity)
Added mass (g: 0-infinity)
P cross-contamination (0-1)
Cross- (re-)contamination levels
Fixed value
Normal
Pert
Discrete
Average
Average
SD
Minimum
Mode
Maximum
Import
Temperature distribution
Fixed value
Normal
Logistic
Gamma
Pert
Uniform
Discrete
Average
Average
SD
alpha
beta
alpha
beta
Minimum
Mode
Maximum
Minimum
Maximum
Import
Time distribution (days)
Fixed value
Normal
Exponential
Logistic
Gamma
Pert
Triangular
Average
Average
SD
lambda
max. time
alpha
beta
alpha
beta
Minimum
Mode
Maximum
Minimum
Mode
Maximum
Nmax (Log CFU/g or ml)
Fixed value
Normal
Uniform
Average
Average
SD
Min.
Max.
Growth estimation
With growth model
Fixed value
Log change (+x or -x)
SD
Work-To-Be-Done (h0)
pH
pH distribution
Fixed value
Normal
Pert
SD of pH
Minimum
Mode
Maximum
aw
aw distribution
Fixed value
Normal
Pert
SD of aw
Minimum
Mode
Maximum
Inhibitor (%, ppm. mM...)
Inhibitor distribution
Fixed value
Normal
Pert
SD of inhibitor
Minimum
Mode
Maximum
Reduction by cooking
Fixed value
Normal
Pert
Uniform
Thermal inct. model
Average
Average
SD
Minimum
Mode
Maximum
Minimum
Maximum
Tref (°C)
Dref (min)
Z (°C)
Cooking Time (min)
SD time
Cooking T (°C)
SD T
Growth model
Exposure
Temperature model
Linear
Cardinal (n=2)
pH model
Presser
Cardinal (n=1)
Aryani pH1/2
aw model
Linear
Cardinal
Food correction Factor
Growth limits
Fixed value
Normal dist.
Pick from dbase
muref (or muopt) 1/h
Tref (or Topt)
Tmin
Tmax
muref (or muopt) 1/h
SD of muref
Tref (or Topt)
Average Tmin
SD Tmin
pHmin
pHopt
pHmax
pH12_Aryani
Ignore reference pH
pH reference
Average pHmin
SD pHmin
awmin
awopt
awmax
aw curvature
Average awmin
SD awmin
MIC of inhibitor
Average MIC
SD MIC
Exponent 1
Exponent 2
Microorganism
Salmonella
STEC
Bacillus cereus
Non-prot Cl botulinum
Psychrot LAB
Pseudomonads
Average muref
SD muref
Tref
SD Tmin
SD pHmin
SD awmin
SD MIC
Iterations
Serving size (g)
Serving Size Distr/tion
Normal
Gamma
SD of Serving size (g)
alpha of gamma dist.
beta of gamma dist.
Dose response
L. monocytogenes susceptible
L. monocytogenes non susc.
Salmonella all serovars
STEC
User-defined Exponential
User-defined Binomial
User-defined BetaBinomial
User-defined BetaPoisson
Initial Prevalence (0-1)
r coefficient
r coefficient
alpha coefficient
beta coefficient
alpha coefficient
beta coefficient
Beta dist. for uncertainty in prevalence
Positives
Total
Poisson distributed cells in foods
Click to render Plots or resample
Growth model with interactions
Risk graph
Sensitivity analysis
Please FIRST read the DISCLAIMER
Scaling factor
Correlation type
Spearman
Pearson
Variable
Pillness
Exposure
Download FULL MODEL
Click to render Plots or resample
Save risk model
Load risk model
Browse...
Exposure & Illness metrics
Annual number of servings
STEP 1: Upload and plot the data to be fitted
Select file or table input
File
Table
Import data (XL) file acc. to the template
Browse...
Click here to download an XL Template
Import
Select plot variable
T
pH
aw
Inhibitor1
Inhibitor2
Inhibitor3
mumax transformation
none
SQRT
Log (ln)
Clear dataset
STEP 2: Set starting values for Cardinal Parameters
T gamma term
Cardinal
Tmin/Tref
pH gamma term
Cardinal
pH1/2-Aryani
pHmin-Presser
aw gamma term
Cardinal
awmin-Linear
muopt [or muref] (h^-1): starting value
Fixed
Tmin: starting value
Fixed
Topt [or Tref]: starting value
Fixed
Tmax: starting value
Fixed
pHmin: starting value
Fixed
pHopt: starting value
Fixed
pHmax: starting value
Fixed
pHmin: starting value
Fixed
pH1/2: starting value
Fixed
pHref
Ignore pHref (use muopt)
pHmin: starting value
Fixed
awmin: starting value
Fixed
awopt: starting value
Fixed
awmax: starting value
Fixed
n_curvature
Fixed
MIC of Inhibitor1: starting value
Fixed
n1 exp. of Inhibitor1: starting value
Fixed
n2 exp. of Inhibitor1: starting value
Fixed
MIC of Inhibitor2: starting value
Fixed
n1 exp. of Inhibitor2: starting value
Fixed
n2 exp. of Inhibitor2: starting value
Fixed
MIC of Inhibitor3: starting value
Fixed
n1 exp. of Inhibitor3: starting value
Fixed
n2 exp. of Inhibitor3: starting value
Fixed
Fit the model
Save values
Restore values
STEP 3. Assess the Parameter Estimates
STEP 4. Assess the Goodness-of-Fit criteria
STEP 5. View the Predicted vs Observed plot
STEP 1: Upload and plot the data to be fitted
Select file or table input
File
Table
Import data (XL) file acc. to the template
Browse...
Click here to download an XL Template
Select plot variable
T
pH
aw
Inhibitor1
Inhibitor2
Inhibitor3
mumax transformation
none
SQRT
Log (ln)
Rename Column
➕ Add Column
➖ Delete Column
STEP 2: Set starting values for Cardinal Parameters
Enter custom model formula:
mumax ~ a * exp(-b * T)
Fit the model
STEP 3. Assess the Parameter Estimates
STEP 4. Assess the Goodness-of-Fit criteria
STEP 5. View the Predicted vs Observed plot
STEP 1: Upload and plot the data to be fitted
Select file or table input
File
Table
Import data (XL) file acc. to the template
Browse...
Click here to download an XL Template
Import
Clear dataset
STEP 2: Set starting values for Cardinal Parameters
Y0 (Log CFU/g or ml): starting value
Fixed
Yend (Log CFU/g or ml): starting value
Fixed
muopt: starting value
Fixed
Lag time: starting value
Fixed
Fit the model
Save values
Restore values
STEP 3. Assess the Parameter Estimates
STEP 4. Assess the Goodness-of-Fit criteria
STEP 5. View the Predicted vs Observed plot
Input of heat processing/microbial thermotoleance data
Choose dynamic or isothermal profile
Constant
Dynamic
Heating duration (sec, min, h)
Heating temperature (°C)
Choose file (XL with 2 columns: t, T) or table
File
Table
Import time-T heating profile (XL)
Browse...
Import data
Enter (optionally) the interpolation step
Tref (°C)
Dref (sec, min, h)
Z value (°C)
Numerical outputs of heat treatment
Visulaziation of heating process
Model selection and input variables
Choose secondary model
From dbase
From file
Equation Editor
Microbial Response
Inactivation
Growth
Import Model from XL file
Browse...
Download XL Template (as in .zip user guide files)
Type the right part of equation without [=], e.g., 0.3*T+0.2*sqrt(pH)..
Choose simulation conditions
Static
Dynamic
Population/Duration panel
Initial population (Log CFU/g)
Physiological state (h0)
Maximum population density (log CFU/g) for growth
Duration (s, min, h, days, etc.)
Generate microbial curve
Simulation graph
Simulation data