Informe del Comité Científico de la Agencia Española de Consumo, Seguridad Alimentaria y Nutrición (AECOSAN) sobre los criterios de seguridad que limiten la exposición a acrilamida producida por la fritura de patatas

Resumo

Acrylamide is an organic compound with a low molecular weight, highly soluble in water, which is formed on cooking certain starchy foods with a low humidity at temperatures above 120 ºC and with low moisture (deep-frying, roasting); this is mainly due to the Maillard reaction, which occurs between certain amino acids, including free asparagine, and reducing sugars (glucose, fructose and others), and which browns food, and also affects its taste. Acrylamide is classified by the International Agency for Research on Cancer (IARC) as a probable human carcinogen (Group 2A), as acrylamide is biotransformed into the metabolite, glycidamide, with genotoxic activity with a special affinity for the nervous system. To date, results from studies on humans have been inconclusive as regards its toxicity. Given that any level of exposure to a genotoxic substance might damage DNA and lead to the appearance of cancer, the European Food Safety Authority (EFSA) is not able to establish a tolerable daily intake (TDI) for acrylamide in food. Instead, the EFSA have estimated the dose range within which acrylamide is most likely to cause a small but measurable incidence of tumours (known as the neoplastic effect) or other potential adverse effects (neurological, pre- and postnatal development and male reproduction). The lower limit of this range (Benchmark Dose Lower Confidence Limit, BMDL10) has been established by the EFSA at a BMDL10 of 0.17 mg/kg body weight/day. For other effects, the most relevant neurological changes observed were those with a BMDL10 of 0.43 mg/kg body weight/day. Although the epidemiological associations have not demonstrated acrylamide to be a human carcinogen, the margins of exposure indicate a concern for neoplastic effects based on animal evidence. Fried potatoes are one of the foods that most contribute to exposure to acrylamide in the general population. The Scientific Committee of the Spanish Agency for Consumer Affairs, Food Safety and Nutrition (AECOSAN) has assessed the characteristics of potatoes as regards the dry matter in the raw material, the presence of reducing sugars and the colour index after frying, which affect the exposure to acrylamide generated as a result of the frying process. In addition, it considers the possible measures to be taken to prevent and reduce the formation of acrylamide in fried potatoes in a domestic environment, including storage temperature or washing potatoes before frying them. In this respect, regarding the characteristics of potatoes affecting the exposure to acrylamide generated as a result of frying, the Scientific Committee concludes that: Given that the water content of a fresh potato ranges between 75-80 %, the content of dry matter in the raw material cannot be more than 25 %. Although the content of reducing sugars may vary considerably over time depending on storage conditions, potato varieties with a low content of reducing sugars, no more than 0.3 %, should be selected. Potatoes intended for frying must be stored at temperatures of around 8 ºC. Large tubers, measuring over 50 mm, should be selected for frying. As regards the recommendations for minimising the production of acrylamide when cooking potatoes at home, the Scientific Committee concludes that: When purchasing potatoes, only use potatoes at optimum ripeness, without green parts or sprouts. When storing potatoes at home, do not store potatoes at temperatures below 8 ºC (do not keep potatoes in the fridge) and avoid prolonged storage. Before frying: cut the potato in thicker chunks or strips rather than thin slices; wash the potatoes after slicing under plenty of tap water and then dry thoroughly with kitchen paper. When cooking: boil potatoes or cook them in the microwave rather than frying them. Avoid frying temperatures of more than 175 ºC at all times. Observe the colour that appears on the surface of the product. Potatoes must be fried until they are a golden yellow colour rather than golden brown and darker coloured potatoes should be thrown away