Methodologies for simulation of gastrointestinal digestion of different controlled delivery systems and further uptake of encapsulated bioactive compounds

Food industry is committed to the consumers demand, having invested in the development and processing of innovative products capable to promote the human health and wellness. The incorporation of bioactive compounds – nutraceuticals – into dietary supplements and functional foods is of great importance to the human body, as they play an important key role in modulating metabolic processes. Encapsulation technology is herein an auspicious strategy to deal with the chemical instability and poor aqueous solubility of lipophilic bioactive compounds. Controlled delivery nano- and microsystems properly devised may protect and increase the stability of several bioactive compounds. Further incorporation of these loaded structures into food formulations might promote the bioaccessibility and bioactivity increase of bioactive compounds. Several gastrointestinal digestion models have been used to assess and identify the delivery systems that fulfil their function, improving the bioavailability of nutraceutical in the human body. This review starts with the presentation of several innovative food products with interest to the consumers. The main carrier-based systems and the encapsulating methods applied to nutraceuticals are further presented. In the last section, an overview about the main simulated gastrointestinal digestion and uptake models are addressed, as well as studies therein performed with delivery systems are discussed. In vitro static models are widely used to evaluate the behaviour of different delivery systems in gastrointestinal tract. The combination of in vitro digestion models and cellular uptake can provide an improved understanding of the most suitable formulations for oral applications.