TABLE 1.
Statistical analysis of the enumeration results from seven lots of stone fruits
| Stone fruit | CFU/fruita |
No. of fruits |
||||||
|---|---|---|---|---|---|---|---|---|
| Minimum | Median | Arithmetic mean | Geometric mean | Maximum | Total | Yielding IVb-v1 | Yielding 1/2b | |
| White nectarine (cv. 1) | 2.5b | 2.5 A | 3.5 | 2.95 A | 15 | 15 | 2 | 0 |
| White nectarine (cv. 2) | 2.5 | 2.5 A | 4.8 | 3.97 A | 10 | 15 | 3c | 4c |
| Yellow nectarine | 2.5 | 2.5 A | 8.0 | 3.16 A | 85 | 15 | 1c | 1c |
| Yellow nectarine, organic | 2.5 | 2.5 A | 4.5 | 3.79 A | 10 | 15 | 4c | 3c |
| White peach | 2.5 | 10.0 B | 42.3 | 14.45 B | 325 | 15 | 13c | 1c |
| White peach, organic | 2.5 | 110 C | 135.8 | 73.37 C | 495 | 15 | 10 | 4 |
| Yellow peach, organic | 2.5 | 190 C | 362.5 | 156.6 C | 2,850 | 15 | 13c | 2c |
| Total | 2.5 | 5.0 | 80.2 | 11.28 | 2,850 | 105 | 46 | 15 |
a
Each fruit weighed 127 to 145 g. Medians were compared by Mann-Whitney test with Holm-Bonferroni correction. Log-transformed values of geometric means were compared with one-way ANOVA. Values with different letters are significantly different (P < 0.05).
b
Half of the LOD (2.5 CFU/fruit) was assumed as the pathogen level for fruits that did not yield L. monocytogenes.
c
One of the fruits had one serotype IVb-v1 isolate and one 1/2b isolate.