Thermal processing contaminants in foodstuffs and potential strategies of control

Over the past decades, researchers from academia, industry, and National authorities and enforcement laboratories, have gained increasing insight in understanding the presence, formation and potential risk to public health posed by the compounds formed during the domestic cooking and heat-processing of different foods. Compounds already intensively studied are the heterocyclic aromatic amines, polycyclic aromatic hydrocarbons, and chloropropanols. Concrete measures have been introduced by the food industry to control certain contaminants, exemplified by the introduction of enzymatic hydrolysis of plant proteins or over-neutralization to reduce concentrations of chloropropanols in savoury flavours. The recent discovery of acrylamide in cooked foods has raised much concern, and sparked intensive scientific studies into the occurrence, analysis, exposure, mechanisms of formation, possible measures of control, and toxicology of the compound. However, since acrylamide formation is directly linked to the desired Maillard reaction that generates important flavour and aroma compounds - as well as chemicals with potentially beneficial health effects - any measures taken must assess the impact on overall quality and consumer acceptance of the food product. In addition, mitigation must be devised in such a way as not to increase the risks for other possibly more severe short and medium to long-term health risks. In this context, understanding the impact of changes in processing on the safety of foods will be of paramount importance. In May 2004 the US FDA published findings of trace levels of furan in different foods, corroborating older data and raising some concerns, albeit without reference to any health risks. Particularly canned and jarred foods that are subject to thermal treatment are apparently affected, as the volatile furan is essentially "trapped" in the food container. Analogous to the acrylamide concern, there is a paucity of knowledge in all scientific domains, i.e. exposure, methods of analysis, mechanisms of formation, toxicology. Finally, a concern that needs to be addressed is the lack of knowledge about the effects of final preparation in food service and domestic situations on the formation of processing contaminants. In essence, consumers should follow sound dietary and health advice by choosing diets based on balance, variety and moderation.