Understanding the dark side of food: the analysis of processed food by modern mass spectrometry

摘要

Do we actually know what we eat How well do we really understand the chemical composition of our daily food These are two questions of utmost importance for consumers, food manufacturers and the scientific community involved in food research. The answer to that question is anything but straightforward. Our knowledge of the chemical composition of food resembles the Roman god Janus, on one side a tremendous knowledge has been built up over the last decade about the chemical composition of the raw materials used for food production. The database FoodDB contains around 28,000 entries of fully characterised chemical compounds found in our daily diet and for many food raw material food scientists are able to account for nearly every molecule present in the raw material.The otherside of Janus is processed food. Most of the food consumed by humans undergoes some sort of processing, either by thermal treatment (baking, roasting, frying, cooking, steaming, etc.), by fermentation, pickling, pressure treatment, irradiation or others. During these processing steps, usually associated with browning or darkening of colour (here referred to as the dark side), the chemical composition of the initial raw material is dramatically altered. The hundreds of components present in theraw material undergo a myriad of chemical transformations producing thousands of novel products. As a rule of thumb, it can be estimated that up to 50 per cent of the compounds present in the food raw materials are decomposed by chemical reactions to produce new products'. Since humans consume the vast majority oftheir food after processing, the actual percentage depending on social and cultural circumstances, up to 80 per cent of food consumed is estimated to be processed prior to consumption. It follows that the majority of the food consumed by humans is processed food.