Depuration of Bivalves: Fundamental Aspects and Complementary Methods to Improve Depuration Process

Bivalve aquaculture production has been increasing globally for the past 20 years with a traditional market value. World aquaculture production comprises 87.5 million metric tons, of which molluscans contributed around 17.7 million metric tons, with bivalves as the major component. Bivalve farming can be made more profitable if the produce meets the basic quality and sanitation standards. Bivalve molluscan shellfish are filter feeders; they feed by filtering large volumes of seawater, accumulating the food particles from their surrounding environment. Seawater, conversely, contains loads of water pollutants, such as bacteria, viruses, heavy metals, microplastics, and biotoxins which are considered unsafe for human health. Hence, bivalves accumulate human pathogenic bacteria, viruses, and biotoxins during filtering action when the environment is contaminated. This poses a potential health risk for bivalve consumers when the bivalves are consumed raw or lightly cooked. Three commercial techniques are used to render the bivalves fit for consumption: cooking, relaying, and depuration or controlled purification. However, depuration helps remove microbes but often fails to eliminate heavy metals, biotoxins, and other hazardous contaminants. Therefore, a proper depuration facility will aid in grabbing a good position in the international bivalves market. This chapter aims to cover the fundamental aspects of depuration and other lab-tested complementary methods and strategies to depuration, improving the process efficiency.