Abstracto

Food matrix: Natural barrier or vehicle for effective delivery of carotenoids from processed foods?

Vassilios Raikos

Carotenoids are lipophilic compounds naturally occurring in plant species where they exert their main biological role as photosynthetic pigments. Due to their chemical structure, carotenoids have the ability to act as antioxidants primarily by scavenging reactive oxygen species. The antioxidant potential of carotenoids is of significant importance to human health and a carotenoidrich diet is recommended for the prevention of a number of chronic and age-related diseases. The bioaccessibily and bioavailabilty of carotenoids is not proportional to their relative abundance in the original food matrix. The structural integrity of the plant material in which they are embedded and their chemical interactions with other food components seem to be critical factors for their release from the food source and their subsequent uptake by cells at the intestinal epithelium. In addition to food microstructure, food processing is also important for carotenoid bioavailabilty. Heat treatment, acidification and exposure to light can induce isomerisation and oxidation of the phytochemical compounds. It is evident that the absorption of carotenoids in a biologically active form is a complex, multi-step process depending on many variables. In this context the aim of this review is to present and critically discuss evidence relating to the association between food processing and carotenoid bioavailability. Emphasis is given on the food matrix composition and the chemical properties of the individual phytochemicals for formulating conclusions on carotenoid availability from processed meals.