LINK TO THE ORIGINAL PAGE CACHED IMAGE 01/11/2007 SAFE FOOD PACKAGING PORTAL

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QSPR-MS WEB-SERVER - PROBABILISTIC MODELING

MIGRARISK efficient pseudo-Monte-Carlo version (v. 1.2)

Notations

NAME DESCRIPTION
_F
food or food simulant
_P
plastics or polymer

_FP

ratio in F and in P
M
migrant or diffusant
0
initial

List of input parameters
(geometry, thermodynamics, transport, initial concentration, contact time)

NAME PHYSICAL PROPERTY
l_P

typical/expected plastic thickness [ SI unit = m)] - TRUE THICKNESS = l_P x l_P*

No safety value (must be measured)

sl_P

normalized shape factor of the distribution of plastic thickness [ no unit)] - l_P* approx by a NORMAL distribution (mean=1, variance=sl_P^2)

Leave 0 if no information

L_FP

mass dilution factor [SI unit: kgF/kgP)] - NO SIDE EFFECT (1D TRANSPORT)

= mass of F / mass of P

No safety value (must be measured)

K_FP

partition coefficient [SI unit: (kgM/kgF)/(kgM/kgP)] - DESORPTION EQUILIBRIUM OBEYS TO HENRY's LAW

concentration in F divided the concentration in P at equilibrium

Safety value = 1000 (almost complete extraction at equilibrium)

D_P

typical/expected diffusion coefficient [SI unit: m2/s] - TRUE DIFFUSION COEFFICIENT = D_P x D_P*

Safety value = must be [over]estimated or measured at a temperature higher than the conditions of use.

For an overestimate, use: Piringer Calculator

sD_P

normalized shape factor of the distribution of the diffusion coefficient [no unit] - D_P* approx by a LOG-NORMAL distribution (mean 1, variance = sD_P^2)

Safety value = 0.5 (0.2 convenient for most applications)

Bi

dimensionless mass Biot number [no unit] - EXTERNAL MASS TRANSFER RESISTANCE DUE TO FOOD TEXTURE/ABSENCE OF STIRRING

Safety value = 1000 (almost no external mass transfer resistance)

C_P0

typical/expected initial concentration in P [SI unit: kgM/kgP] - TRUE INITIAL CONCENTRATION = C_P0 x C_P0*

Safety value = 5000 ppm (maximum concentration for common additives)

sC_P0

normalized shape factor of the distribution of the initial concentration in P [no unit] - C_P0* approx by a NORMAL distribution (mean 1, variance = sC_P0^2)

Safety value = 0.2

t

typical/expected contact time [SI unit s] - TRUE TIME = t x t*

Default value = 10 days (according to monolayer regulation)

st

normalized shape factor of the distribution of contact time [no unit] - t* approx by a WEIBULL distribution (mean, variance = st^2)

Default value = 1.3

PARAMETER FORM (see above for details)

parameter
typical
value
unit
shape
factor
unit
l_P
-
L_FP
kgF.kgP-1
0
-
K_FP
kgF.kgP-1
0
-
D_P
-
Bi
none
0
-
C_P0
-
t
-


Be aware that calculations require several minutes (typically 3 min).

©2006 by INRA\Olivier Vitrac