The tested tuna dumpling stuffing with an initial bacterial count
of 2 log CFU/g did not change the bacterial count during the 8-
week storage at -20 C (Fig. 4). Although the bacterial count of E.
aerogenes in high spiked sample (5 log CFU/g) did not change during
the initial 4 weeks of storage at 20 C, the counts decreased to
4.8 log CFU/g after eight weeks. However, it (4.8 log CFU/g) was not
statistically different with inoculated bacterial counts (P > 0.05).
No histamine was detected in any of the high or low spiked samples
tested during the 8-week storage at 20 C (data not shown).
Therefore, histamine production by E. aerogenes in both spiked
samples was effectively controlled by frozen storage at 20 C.
Behling and Taylor (1982) and Kim et al. (2002) reported that storage
of seafood at 0 C or below limited histamine formation to negligible
levels.