Optimizing fruit and vegetable by-products/wastes exploitation: diversity, safety and biotechnological innovations based on lactic acid bacteria

Over the last few years, global demand for fruit and vegetable production has increased as the world's population and demographics have shifted toward healthier lifestyles. Together, the agri-food industry has continued to grow worldwide, driven by advances in planting technology and the optimization of production processes, resulting in the generation of massive agricultural residues. These residues account for almost 50% of the primary material biomass, and they are rich in high-value components such as antioxidants, pigments, flavors, and dietary fibers. In this context, the circular economy concept has been proposed as a sustainable approach that aims to use agri-food by-products/wastes to reduce environmental pollution. Lactic fermentation is one of the earliest, versatile, and low-cost food processing techniques that utilizes lactic acid bacteria (LAB) to induce desirable biochemical transformations. This review proposes a holistic approach to this type of valorization, highlighting the different categories of fruits and vegetables, the effects of seasonality, the dynamics that lead to the production of by-products/wastes, the safety issues associated with the different contaminants, the regulatory environment, and critically overviewing the recent studies that proposed fruit and vegetable by-products/wastes processing using LAB as bioresources.