ABSTRACT
Anthocyanins have a high potential in the food sector not only due to their coloring properties but also due to their high antioxidant activity. Their structural diversity, susceptibility to heat, pH, and copigmentation complicate its extraction and purification. The use of high hydrostatic pressure (HHP) assisted extraction has proven to be a good alternative to conventional techniques as it combines elevated pressure (100–800 MPa), moderate temperatures (30–60°C), and short processing times (3–10 min). The HHP process is based on the Pascal and Le Chatelier’s principles which state that pressure is uniformly transmitted and distributed in all directions. HHP allows the enhancement of mass transfer rates by increasing cell permeability and increasing the diffusion of secondary metabolite, which leading to higher extraction yields, fewer impurities on the final extract and the possibility of extractions at room temperature with preservation of thermo-sensitive structures.
This review examines the basic principles of the HHP technology, including its mechanisms, analytical procedure and its effects on plant materials as well as a discussion on the most important parameters that affect the performance of this technology, its advantages, and disadvantages. Lastly, the applications of HHP for the recovery of phenolic compounds, with emphasis on anthocyanins, are discussed.
ACKNOWLEDGEMENTS
Thanks are due to Dra. María José Navas and Dra. Ana María Jiménez for the valuable help provided in the search of the bibliography and in the preparation of the tables.
Compliance with ethical standards
Conflict of interest: The authors declare that they have no competing interests.