Figure 4. Histogram of normalized core temperatures: passed normality test Figure 5. Normal probability plot of normalized core temperatures: passed normality test three standard deviations (range/d2) spread increased; see Fig. 8. As the range gets larger, the standard deviation increases, and tolerance limits widen. The net impact of this finding is that the factory needs to cook the fish longer to move the median higher and to make certain the lower tolerance limit at least meets the pre-set target of 60°C. This approach fully supports the argument that the factory needs to reduce the range and variance of the core temperatures to reduce overcooking of the fish. DISCUSSION Implementing core temperatures as a monitoring tool for a tuna processing CCP under HACCP To use the core temperature monitoring procedure as a tool for a precooking CCP, the factory will need to integrate this procedure into their existing HACCP plan. The necessary prerequisites will be presented in a future publication. July/August Food Protection Trends 279