The global seaweed industry is a multi-billion dollar sector of rapidly growing proportions. Commercial uses for New Zealand seaweed are wide and varied - ranging from bacteriological grade agar through to high value bioactive compounds for agriculture.
The use of seaweed by man dates back to early human civilisation when coastal cultures relied on it for sustenance. The first recorded use of seaweed can be traced to ancient Asian literature dating 2700 BC for use in food and medicine. Red seaweeds were widely used by Europeans for food, livestock feed, medicine, and crop ‘fertilisers’. Maori and Tongan cultures often used brown seaweeds as a food source and to create cultural garments.
Today, the global seaweed industry is a sector of considerable and rapidly growing proportions. It provides a wide variety of products with an estimated annual value of $US 5.5 - 6 billion. Of this human foods contribute US $5 billion while hydrocolloids (agar, carrageenan, alginate) account for the majority of the remaining US $1 billion. New Zealand’s industry has been largely focused on bacteriological grade agar extracted from Ptercocladia and agricultural biostimulants from Ecklonia radiata.
Over 8 million tonnes of wet seaweed is harvested annually from 35 countries worldwide. Exponential growth in the industry over the past 50 years has seen demand gradually outstrip supply from wild stocks, resulting in the development of cultivation methods. This was seen with Laminaria and Undaria for food and Chondrus crispus for carrageenan. Alginate and agar production continues to rely on supply from either harvested wild or beachcast stocks.