Engaging with strategies to impede post mortem hyperpigmentation in commercial crustaceans

Hyperpigmentation (or melanosis) in commercial shellfish is a non-infectious condition characterised by the gross accumulation of the pigment, melanin. Consequently, the displeasing aesthetics lead to a severe reduction in shelf life and market value of crustaceans worldwide, concurrent with an increase in waste. Various preventative measures have been introduced, the most recent of which avoid the use of the traditional treatment, sodium metabisulphite, since this has been linked with occurrences of occupational illness. Two proteins are known to contribute to hyperpigmentation, namely phenoloxidase and hemocyanin-derived phenoloxidase. Both enzymes belong to the family of type-3 copper proteins, and when activated, accommodate phenolic compounds into their active sites, eventually leading to melanin synthesis. In contrast to cellular phenoloxidase, the inhibition of hemocyanin-derived phenoloxidase is poorly understood. In this proceeding chapter, we provide an overview of the current practices employed to ameliorate unwanted post mortem hyperpigmentation and contextualise these data with respect to food security concerns.