Macroalgae are used as fresh or mildly processed in foods and consumables. Moreover, they are used as raw material for various extracts, the most important ones being agar, alginates and carrageenan. Currently, the use of biologically active macroalga extracts as food and feed supplements is growing. In addition, there is interest towards novel macroalga based food additives such as food flavours, colourants and nutrients.
Macroalgae are divided into three classes: green, red and brown macroalgae (Chlorophyta, Rhodophyta and Phaeophyta, respectively), of which the brown macroalgae species are the commercially most important ones counting for two-thirds of the globally produced macroalga. Brown macroalgae are followed by red macroalgae with a share of approximately one-third and green macroalgae with a share of 5% of the global macroalgae production (Lorenzo et al. 2017). Currently, over 200 macroalga species are used globally and the total production reaches over 30 million tons. Regardless of the diversity of edible and otherwise useful macroalga species, 98% of the seaweed production is accounted for only five macroalga genera (Pereira et al. 2008, Table 1). Utilisation of more diverse species suffers from various bottlenecks including lack of suitable cultivations techniques as well as of the limited distribution and natural abundance of species. Moreover, research on the biochemical composition, nutritional and bioactive properties and sensory characteristics of novel seaweeds is needed to unlock their potential as food or source of natural compounds.