Selective Extraction of Biocompounds from Stevia rebaudiana Bertoni Leaves Using Electrotechnologies
Résumé
Stevia rebaudiana Bertoni plant is a potential source of sweeteners that have attracted the attention of food industries for many years. This growing interest is mainly related to their high sweetener compared to sucrose (up to 300 times) and their suitability as low caloric compounds. Conventional extraction techniques (e.g., hot water extraction) have been used for decades to extract sweeteners from S. rebaudiana leaves. Although efficient, these techniques present many limitations including the long extraction time, the use of toxic solvents, and the high consumption of energy. To overcome these problems, there is growing interest in developing new intensification processes that increase the extraction and reduce the impurities generated during the process in order to reduce and/or eliminate the downstream purification steps. In recent decades, there have been increased efforts by the scientific community to develop alternative processes for conventional extraction. For instance, treatments such as ultrasound, microwave, supercritical fluid extraction, and particularly electrotechnologies have been evaluated, showing promising results and making them on the verge of commercialization. Among electrotechnologies, pulsed electric fields (PEF) and high voltage electrical discharges (HVED) were the most evaluated for the extraction of sweeteners from Stevia rebaudiana Bertoni leaves and are detailed in this chapter.