Table 14.
Calculated L. monocytogenes concentrations (CFU/g) on corn and green peas at the end of the production process (i.e. performance objective) that would be compatible with the food safety objective (FSO) of 100 CFU/g at the moment of consumption without cooking, for different times and temperatures of storage
| Vegetable | Storage temperature (°C)a | Storage time (h) | |||||
|---|---|---|---|---|---|---|---|
| 12 | 24 | 48 | 72 | 96 | 120 | ||
| Corn | 5 | 97b (55)c | 54 (31) | 17 (9) | 5 (3) | 2 (0.9) | 0.5 (0.3) |
| 8 | 64 (34) | 22 (12) | 3 (1) | 0.3 (0.2) | 0.04 (0.02) | 0.004 (0.002) | |
| 9 | 52 (28) | 15 (8) [5–24]d | 1 (0.6) [0.4–5] | 0.1 (0.05) | 0.008 (0.004) | 0.0006 (0.0003) | |
| 12 | 23 (15) | 3 (2) | 0.07 (0.05) | 0.002 (0.001) | 0.00003 (0.00002) | 0.0000007 (0.0000004) | |
| Green peas | 5 | 95b (63)c | 59 (39) | 23 (15) | 9 (6) | 4 (2) | 1 (0.9) |
| 8 | 62 (34) | 21 (12) | 2 (1) | 0.3 (0.2) | 0.03 (0.02) | 0.004 (0.002) | |
| 9 | 49 (26) | 13 (7) [19–24]d | 0.9 (0.5) [0.7–14] | 0.06 (0.03) | 0.004 (0.002) | 0.0003 (0.0002) | |
| 12 | 20 (10) | 2 (1) | 0.02 (0.01) | 0.0002 (0.0001) | 0.000002 (0.000001) | 0.00000002 (0.00000001) | |
5°C corresponds to the storage temperature recommended on the product labelling (PROFEL, 2019); 8°C is the 75th percentile of the refrigerator temperature in the survey by Roccato et al. (2017); 9°C is the temperature considered in the challenge tests reported in the draft PROFEL guidelines to mimic reasonably foreseeable temperature abuse in household refrigerators; 12°C is the temperature at the consumer phase considered in the EURL‐Lm guidelines to conduct shelf‐life studies (EURL‐L. monocytogenes and ANSES, 2019b) when the percentile 95% of the actual distribution of the temperatures at consumer level is not known.
Based on Kataoka et al. (2017) including the thawing/lag time.
Based on Kataoka et al. (2017), without including the thawing/lag time.
Based on the challenge tests described in the draft PROFEL guidelines, considering following situations: (1) batch 1 with high‐volume loading of the refrigerator simulating defrosting in catering or business to business refrigerator scenario (331 litre refrigerator holding in total 35–55 of 200 g packs of frozen vegetables) and using a four‐strain cocktail of L. monocytogenes (i.e. including the L. monocytogenes MLST 6 multi‐country outbreak strain); (2) batches 2 and 3 with low volume loading of the refrigerator simulating defrosting in household refrigerator scenario (331 litre refrigerator holding in total 7–11 of 200 g packs of frozen vegetables) and using the same four‐strain cocktail of L. monocytogenes, (3) as batch 3 but using a three‐strain cocktail of L. monocytogenes (i.e. excluding the L. monocytogenes MLST 6 multi‐country outbreak strain).