90 for 90. Evaluation of heat treatments of live bivalve molluscs

Aims: The European Food Safety Authority (EFSA) was asked to deliver a Scientific Opinion on the evaluation of heat treatments, different from those currently established in the EU legislation, that could be applied to live... [ view full abstract ]

Aims: The European Food Safety Authority (EFSA) was asked to deliver a Scientific Opinion on the evaluation of heat treatments, different from those currently established in the EU legislation, that could be applied to live bivalve molluscs. Of particular relevance are the achievement of at least 90°C for at least 90 s in the mollusc flesh and the inactivation of viruses.

Methods and Results:  Hazard identification concluded that Norovirus and Hepatitis A virus (HAV) are the most important viral hazards associated with bivalve molluscs. A HAV thermal inactivation model was developed to identify equivalent processes to the ‘notional’ heat treatment of 90°C for 90 s (without heat-up and cool-down times) between 72 and 100°C. The mean D₉₀ and z-values of the model were 54 s and 27.5°. Theoretical and industrial profiles showed that significant variations in HAV log reduction are obtained depending on the process design. A risk assessment case study was developed to show the relationship between a Performance Criterion (PC) for the HAV reduction during heat treatment of bivalve molluscs and the human risk at consumption. 

Conclusions:  If risk managers establish an Appropriate Level of Protection (ALOP), this can be translated to a PC and a Process Criterion (PrC) using the HAV thermal inactivation model. An F-value is a more appropriate PrC than the current time–temperature combination since it takes into account the whole profile during heat treatment.