Table 2.
Summary of the generic Quantitative Microbiological Risk Assessment (mgQMRA) input data for blanched frozen vegetables (bfV) consumed with or without cooking for the baseline scenario and best‐case and worst‐case uncertainty scenarios
| Parameter | Distributiona | Input parameters | Baseline scenario | Input parameters for best‐case uncertainty scenario | Input parameters for worst‐case uncertainty scenario | Comments or percentiles used for best‐case and worse‐case |
|---|---|---|---|---|---|---|
| Prevalence of L. monocytogenes in bfV | Beta |
alpha = (147 + 1) beta = (1,288‐147 + 1) |
p = 0.114 | p = 0.098 | p = 0.133 | 2.5th and 97.5th percentiles |
| Initial concentration of L. monocytogenes in bfV (log10 CFU/g) – surveys/studies + FBO data | Beta‐general |
Min = −1.69 Max = 5 Shape 1 = 0.094 Shape 2 = 2.839 |
Used as baseline |
Shape 1 = 0.121 Shape 2 = 3.819 |
Shape 1 = 0.073 Shape 2 = 2.217 |
2.5th and 97.5th percentiles |
| Exponential growth rate (expressed as log10 /h) of L. monocytogenes in heat‐treated vegetables at a reference temperature of 5°C (EGR5°C) | Lognormal |
Mean = 0.0117 SD = 0.00816 Max = 0.0319 |
All scenarios | All scenarios | All scenarios | Not evaluated in the uncertainty analysis |
| Serving size of vegetables (g) | Constant | Mean = 49 | Used as baseline | 31 g | 106 g | 20th and 80th percentiles, respectively |
| Maximum population density (log10 CFU/g) of L. monocytogenes in vegetables | Constant | Mean = 7.83 | Used as baseline | 5.43 | 9.78 | Minimum and maximum Nmax |
|
Consumer storage time outside the freezer = (remaining shelf‐life × proportion being used) Remaining shelf‐life (h) Proportion being used |
Exponential with rate = 1/mean shelf‐life Beta‐Pert |
Mean shelf‐life = 12 h (‘cooked’ vegetables) Mean shelf‐life = 24 h (‘RTE’ vegetables) Max = 96 h Minimum = 0 Most likely = 0.3 Maximum = 1.1 |
All scenarios | All scenarios | All scenarios | Not evaluated |
| Storage temperature at consumer fridge (°C) | Truncated Normal |
Mean = 5.9°C SD = 2.9°C Lower = −2°C Upper = 15°C |
All scenarios | All scenarios | All scenarios | Not evaluated – same for all foods |
| Reduction of L. monocytogenes in the event of cooking (log10 units) | Beta‐Pert |
Min = 1 log10 Most likely = 5 log10 Maximum = 9 log10 |
Used as baseline | Same as baseline | Most likely = 3 | Reasonable assumptions |
| Dose response of L. monocytogenes for the elderly population | Log‐normal exponential model |
Females: Mean = −13.7020 SD = 1.6154 Males: Mean = −13.5598 SD = 1.6154 |
All scenarios | All scenarios | All scenarios | Not evaluated‐ The same uncertainty over all food categories so less important for the uncertainty related to the comparison |
| Annual number of servings of bfV for the elderly population | Constant | 2.65 × 109 (females); 2.28 × 109 (males) | Baseline | 1.63 × 109 (females); 1.38 × 109 (males) | 3.15 × 109 (females); 2.74 × 109 (males) | Public health impact evaluated in scenario analysis |
| Proportion of servings of bfV consumed cooked or uncooked by the elderly population | Constant | Cooked = 50, 60, 70, 80, 90, 100 and uncooked = 50, 40, 30, 20, 10, 0 | Proportions based on label information Willis et al. (2019): cooked: 96%; uncooked = 4% | Proportions based on label information Willis et al. (2019): cooked: 77%, uncooked = 23% | Different proportions were evaluated in separate scenario analyses |
The same distributions as used in the gQMRA in EFSA BIOHAZ Panel (2018), except for the log10 reduction for cooking which was not included in that model.