Cocoa Bean Shell: A By-Product with High Potential for Nutritional and Biotechnological Applications

Cocoa bean shell (CBS) is one of the main solid wastes derived from the chocolate industry. This residual biomass could be an interesting source of nutrients and bioactive compounds due to its high content in dietary fibres, polyphenols and methylxanthines. Specifically, CBS can be employed as a raw material for the recovery of, for example, antioxidants, antivirals and/or antimicrobials. Additionally, it can be used as a substrate to obtain biofuels (bioethanol or biomethane), as an additive in food processing, as an adsorbent and, even, as a corrosion-inhibiting agent. Together with the research on obtaining and characterising different compounds of interest from CBS, some works have focused on the employment of novel sustainable extraction methods and others on the possible use of the whole CBS or some derived products. This review provides insight into the different alternatives of CBS valorisation, including the most recent innovations, trends and challenges for the biotechnological application of this interesting and underused by-product.

Automated summary

Cocoa bean shell (CBS) is an abundant waste from the chocolate industry, which has high potential for the recovery of valuable compounds such as dietary fibres, polyphenols and methylxanthines. It can be used for the production of antioxidants, antivirals, biofuels, food additives, adsorbents and corrosion inhibitors. The review highlights the different valorisation alternatives for CBS and discusses the recent innovations, trends and challenges in its biotechnological application.