The goal of the development of sustainable seaweed farming is to ensure that the commercial farming of seaweed has a minimal adverse effect on the marine environment. Methods for cultivation include the bottom monoline method, fixed bottom long-line method, floating bamboo method, bamboo raft method, mangrove stakes, net cultivation, and integrated multitrophic aquaculture method ( Radulovich et al., 2015). The species is selected based on the ultimate application (food, feed, hydrocolloid, biofuel, and bioactive compounds) and suitability of the environment. The development of more robust and cost-efficient farming systems is needed, especially in the offshore environment.
Thus, it is critical to create new strains of marine algae that are light, thermally tolerant, and resistant to disease. The diseases, including “ice-ice,” are also a challenge for seaweed farming because it causes damage to the seaweed ( Egan et al., 2014). Long-spine sea urchins and turtles are causing physical damage to the farm or injuries to the farmers. Site selection is the most significant parameter in seaweed farming ( Yulianto et al., 2017). Seaweed farming is defined as the optimized culturing of seaweed crops in seawater for growth and ensuring continuous photosynthesis. Any seaweed can be attached to substratum and grow as long as the availability of sunlight, nutrients, oxygen, and carbon dioxide (CO 2), despite the depth.
Hence the ability of seaweed to grow in the form of attachment to floating objects is the basis of seaweed farming. Few brown seaweeds are free-floating because of their air-filled bladders ( Milledge and Harvey, 2016). Seaweed is plant-like species attached with a holdfast to shallow coastal waters, requires sunlight and substratum for its growth, but does not have root to supply nutrients, as whole body is involved in nutrient absorption and photosynthesis. As the demand for seaweed food hydrocolloids continues to grow and with the ongoing research and development in seaweed cultivation, the processing of seaweeds together with downstream product development and novel applications constitute a vibrant industry where the extraction of hydrocolloids from seaweed biomass forms the foundation of the overall seaweed processing industry ( McHugh, 2003). Today, Indonesia has become the world’s largest producer of agar- and carrageenan-bearing seaweeds, whereas China is the world’s largest combined processor of seaweed hydrocolloids using domestically cultivated seaweeds as well as large amounts of imported raw materials.
Today, the seaweed hydrocolloid business represents the main part of the seaweed processing industry, and its activities are centered on the sourcing of raw seaweeds extraction of the hydrocolloids and sales of alginate, carrageenan, and agar in addition to some relatively minor products and applications such as iodine, mannitol, and seaweed fertilizers.Īlthough the extraction and commercial applications of seaweed hydrocolloids were initially developed in Europe and North America, the development of seaweed farming in Asia and the economic changes in the Asia–Pacific region have changed the industry’s structure. Seaweed-derived food hydrocolloids have been known for over a long period of time, and the processes of their extraction from the respective types of seaweeds have also been evolving for a long time. Yimin Qin, in Bioactive Seaweeds for Food Applications, 2018 3.1 Introduction