Vegetable waste and by-products to feed a healthy gut microbiota: Current evidence, machine learning and computational tools to design novel microbiome-targeted foods

Abstract

Food waste management is a key issue to global food security and friendly environmental governance. Worldwide, one-third of food produced for human consumption is lost or wasted along the food supply chain, primary production and food processing representing the most significant loses. Therefore, the need to achieve zero waste production schemes is becoming a priority to meet Sustainable Development Goals. Increasing evidence points towards vegetable food waste as a rich source of a wide array of carbohydrate structures and fibres providing the opportunity to identify and develop alternative approaches to valorize agro-food waste. This review describes the valorization of vegetable waste and by-products via production of (novel) substrates targeted to gut microbiota modulation, emphasizing the importance of raw materials and structural-functional properties of carbohydrates. Furthermore, we propose a novel framework for the rational selection of vegetable sources with potential prebiotic activity, based on machine learning and other computational tools applied to available literature and public database information. Integration of the body of knowledge within the field of vegetable food waste valorization, from different perspectives, allows a rational selection of carbohydrate-based substrates with promising prebiotic activities. By exploring the interactions among dietary fibre and gut microbial ecosystems using computational tools fed with structural, functional and genomic data, we can identify substrates with potential to selectively stimulate gut commensals, in agreement with experimental evidence. Our approach establishes a new framework that can be extended to a wide range of commensal microbes and carbohydrate structures.