The utilisation of by-products generated by agro-industries through the use of all the parts that make up vegetables, for example, has been used as a sustainable and innovative alternative since biologically active substances present in these residues are being discovered that can contribute to health. It is therefore necessary to use a process that makes it possible to extract these substances, since eating the peel in its whole form is unattractive. The choice of technique for extracting bioactive molecules is made according to the potential application of these extracts, particularly the use of hydroalcoholic solutions in the food industry. Based on the investigation of a sustainable alternative for obtaining bioactive extracts of food interest, this book proposes a study that lists the best conditions for obtaining and concentrating these biologically active substances in plant material.