A Flexible Schema for the Valorization of Citrus Peels
Summary
Large quantities of citrus fruits are eaten and processed in the Netherlands.
Unfortunately, more than half of the fruit mass, including peel, pulp, and seeds, is
discarded, often ending up in incinerators or landfills. Not only is this environmentally
problematic, but it is also a waste of organic material that contains numerous valuable
components. This review explores various pathways for the valorization of citrus peels
that could be implemented at a fruit processing facility. The pathways are split into two
sections: extraction and fermentation. The extraction section details the initial
mechanical processing of the peels and outlines direct extraction techniques, with
particular emphasis paid to subcritical water extraction and hydrodistillation. The
fermentation section discusses the pros and cons of solid state and submerged
fermentation and outlines some of the potential value-added products that could be
obtained.