Innovative processing strategies and technologies to obtain hydrocolloids from macroalgae for food applications

•Novel technologies for improved extraction yields of hydrocolloids.•Clean and green innovative approaches for hydrocolloids are reviewed.•Synergistic combinations of novel and/or conventional technologies are reviewed.•Challenges associated with industrial scale up of technologies. The macroalgal hydrocolloid industry is a rapidly growing industry with an annual growth in the global production of 2–3 %. Hydrocolloids from macroalgae are mainly in the form of polysaccharides with other nutrients, such as vitamins, minerals, and proteins. Due to its potential industrial applications, macroalgae have been used as raw materials for hydrocolloids extraction. Compared to the conventional extraction methods, emerging innovative assisted extraction technologies (e.g., Ultrasound/Microwave assisted extraction) have been developed to maximise the extraction yields, efficiency and thereby, maintaining sustainability along the process. These novel techniques are considered as clean and green strategies, with a potential for a large-scale production; thus, avoiding or reducing the use of chemicals. However, more research is required to establish their mechanism of action in order to finally implement them at industrial level. This paper reviews the most relevant strategies and technologies involved in the production of hydrocolloids from macroalgae.