Effect of processing on the bioaccessibility of bioactive compounds - A review focusing on carotenoids, minerals, ascorbic acid, tocopherols and polyphenols

Health benefits of bioactive compounds depend not only on the intake levels but also on their bioavailability (BAv). In vitro methods to simulate gastro-intestinal digestion allow to determine the bioaccessibility (BAcs) of these compounds, as a first step of BAv, and can be used to evaluate the effect of processing on them to design functional foods with increased health-promoting effects. The impact of traditional processing technologies such as thermal treatment and novel emerging non-thermal technologies such as high pressure processing, high-intensity pulsed electric fields and ultrasound on BAcs of bioactive compounds as carotenoids, minerals, ascorbic acid, tocopherols, polyphenols and total antioxidant capacity is described in this review article. In general, combination of high pressure processing and thermal treatment in the presence of oil for carotenoids, thermal treatment for ascorbic acid and polyphenols, and high pressure processing for minerals, tocopherols and total antioxidant capacity would increase BAcs of these bioactive compounds. Ultrasound processing is likely to improve polyphenol compound BAcs and high-intensity pulsed electric fields could improve carotenoid, vitamin C and phenolic compounds BAcs, as well as antioxidant activity. However, general guidelines seem not to be applicable for every case study and more research in this field is needed.