Substances with cancerogenic potential in processed meat

Abstract

Meat represents an important food in human nutrition as a source of essential amino acids, fatty acids, and micronutrients, but in recent years the emphasis is given to the carcinogenic potential of red meat and processed meat. Red meat includes the meat of pigs, ruminants, and horses, and its color is proportional to the iron-rich myoglobin content. Hem-iron is attributed to show pro-carcinogenic effect due to N-nitroso compounds catalysis, food lipids oxidation, and pro-oxidative action in the body. But these reactions could be reduced by slowing its resorption, nitrosylation, and oxidation with calcium (milk products) and antioxidant (plants) rich food. As meat is consumed after the heat treatment which could lead, to a greater or lesser extent, to the formation of heterocyclic aromatic amines (HAA) as potentially carcinogenic substances, which occurs extensively during baking and roasting, but negligible during boiling. So, it is important to choose an appropriate method for meat heating, but also is it possible to reduce the bioavailability of HAA and modify their metabolism in the body after ingestion through plant antioxidants, dietary fiber, fermented food (yogurt, sauerkraut) intake, as well as the bioactive substances from the meat itself (conjugated linoleic acid), which can significantly reduce harmful effects of HAA. By meat products, the most important harmful substances are N-nitrosamines (NN) in cured (preserved with nitrate/nitrite), as well as polycyclic aromatic hydrocarbons (PAH) in smoked meat products. NN content differs in meat products and is influenced by the nitrate/nitrite amount used, but also by the heat treatment and ripening process. Frying and baking of cured meat products lead to the highest NN content, especially in fried cured bacon. Although there are many studies about nitrite replacement in meat products with plant-based ingredients, nitrites are still indispensable, especially because of their antimicrobial effect on Clostridium botulinum. PAH content could be controlled by adequate wood pyrolysis temperature, construction of the smoking chamber, smoke density and purification, the product composition (fat reduction, artificial casings), and even reduced by the activity of some lactic acid bacteria strains as well as some spices. Considering that the formation of carcinogenic ingredients could be reduced during production, and their availability, absorption, and expression reduced by well-balanced meals during consumption, red meat and meat products should not always and unconditionally be characterized as harmful, especially if we are aware of the valuable nutritive and bioactive compounds originating from the meat itself.