How prebiotics have been produced from agro-industrial waste: An overview of the enzymatic technologies applied and the models used to validate their health claims

Abstract

The disposal of waste from the food industry represents a major environmental concern. Nonetheless, agro-industrial by-products can be enzymatically converted into low-cost high-value-added products, such as prebiotics, while contributing to a circular economy. As a first approach for health claims validation of these novel products, several gastrointestinal models have been used. The main objective of this review is to provide a comprehensive overview of the advances in the enzymatic technologies applied to the production of prebiotics from agro-industrial wastes. The strategies used in the conversion of the wastes, including pre-treatment processes, type of enzymes applied, and the reaction conditions used are revised. Finally, from data obtained by in vivo trials and in vitro gastrointestinal simulation, the functionality of the produced prebiotics and their biological mechanisms of action are discussed. Enzymatic processes have proven their efficiency for the conversion of low-cost agro-industrial wastes into commercial valuable compounds, such as prebiotics. Still, the potential of enzymes for the bioconversion of the vast diversity of existing wastes has yet to be explored. By researching different setups of the enzymatic reaction and optimization of the reaction conditions, greater yields of the prebiotic extraction or synthesis may be achieved. Also, despite the many available gastrointestinal models, few studies have been done on the biological function of the prebiotics obtained from agro-industrial wastes, which has been a drawback in the validation of health claims associated with these novel products.