ABSTRACT

This chapter presents an overview of the types of macroalgae and their properties. It addresses processes for isolating carbohydrates for biofuel production, and biochemical and thermochemical conversion processes for transforming these carbohydrates into liquid biofuels and biomethane. The chapter discusses uses of the proteins in macroalgae as part of the wider picture of using seaweeds as feedstock for the future biobased economy. It outlines cascading biorefinery approaches for macroalgae, focusing on the carbohydrates for biofuel production and on the protein fraction. The three main components in macroalgae are carbohydrates, proteins, and minerals. In macroalgae, the carbohydrates can be divided into storage carbohydrates, which function as a food reserve, and structural carbohydrates, which are found in the cell wall and give mechanical strength and prevent the seaweed from dehydration. Macroalgae have been used since ancient times as food, fertilizer, and a source of chemicals, pharmaceuticals, and food ingredients, mainly in Asia.