Kelp species are typically harvested in a short period during the spring months, creating a processing bottleneck for the farmers. After dehydration and cutting, most of the biomass is frozen. As drying techniques become more common and new technologies and innovations emerge worldwide, various research and development initiatives, as well as technical and financial support organizations, are assisting Alaskan farmers and processors in implementing and integrating efficient drying capacities.
Dry kelp generally weighs about one-tenth of the harvested biomass. It's important to note that exact conversion ratios can vary significantly across harvests, regions, and processing methods.
Post-harvest handling refers to the crucial steps in stabilizing seaweed and getting it ready for sale, ensuring it reaches the market in the best condition possible. The kelp value chain in Alaska usually follows a similar pattern, but the processing stage involves various techniques and processes. Farmers often consider this stage the most significant bottleneck in the value chain.
Processing techniques include:
Rinsing and trimming
Farmers ensure their harvest is clean by rinsing off loose sediment or biofouling, by dunking the sections of the growline closest to the boat back into the water before hauling it in, effectively washing off debris. Alternatively, farmers may use a deck hose to spray down the kelp as it's brought aboard, helping maintain the harvest's quality and cleanliness.
Inspection
After rinsing, the seaweed is inspected on a belt, either on the boat or in the processing facility.
The harvested seaweed is taken from the boat into tote bags and placed in blue containers, which are standard equipment for seafood processors
The seaweed is placed on the inspection belt by a forklift
The seaweed is inspected and moved along the inspection belt
In this particular case it is directly packaged after inspection
Grinding/shredding
To process seaweed most effectively, it is often ground or shredded before it is stabilized. This can either be done on land in a processing facility or on the water.
As soon as you take the seaweed out of the water, it immediately starts to degrade. You've got 12 to 24 hours to get it into a stable format before it starts to lose value quite precipitously.
GreenWave has developed a tool that allows for grinding the kelp on the boat with a spinner. The ground kelp is then transported into tote bags, which allows for more time efficiency on deck and in the processing facilities, ensuring that the seaweed is stabilized efficiently. Mother of Millions uses a similar processing method, and the sizes can be adjusted to the consumer's preferences.
GreenWave is using a similar machine to grind the seaweed on board harvesting vessels
Another tool to move the ground seaweed up into the tote/harvesting bags
Brianna Murphy from Mother of Millions with the grinder behind the inspection line on the company's vessel
A commonly used technique for stabilizing seaweed is blast freezing, which is widely available in Alaska. The seaweed is placed in plastic trays and then in blast freezers, commonly used for fish processing. The seaweed can be frozen whole or after grinding.
Removing frozen kelp from a blast freezer
Shredded and frozen seaweed stored in plastic tray
Frozen seaweed ready to be sold
Our farm and this handling process is 100% organic certified. I believe we're the only fully certified seaweed company in Alaska.
The processing facilities can be used for various seafood functions, as kelp is only processed in April and May. This is a win-win situation for seaweed farmers in Alaska because the permits already exist, many of the equipment and requirements, such as HACCP, have been taken care of, and they can drive the costs down.
Drying
Drying is one of the biggest challenges for kelp farmers worldwide, as kelp is 90% water. Currently, Alaska has limited drying capacity and kelp is difficult and expensive to process.
The controls of a drum dryer at Barnacle Foods
This drum dryer was originally designed for drying tea leaves but has been customised to dry kelp
Hanging and drying seaweed in a high tunnel greenhouse is a traditional and labor-intensive drying technique.
Using salt to dry kelp
Milling
After drying, the seaweed is often milled to suit different use cases, such as shipping it effectively or for product development. Both Ebbtide and Barnacle use the same milling machine.
Ebbtide and Barnacle Foods use the same milling machine
A worker placing dried seaweed into a milling machine
Seaweed can be milled into different sizes, depending on customers' specifications
Joint innovation projects
Evaluating and sharing methods to efficiently dry kelp for rural communities
Seeking a cost-effective method for drying kelp on a small scale in remote coastal communities to enhance the growth of the mariculture industry and involve rural and Native communities. These communities face high energy costs, limited labor capacity, and market entry barriers.
Primary stabilization of seaweed using drying techniques
Blue Evolution, in collaboration with Sun'Aq Tribal Enterprises via Wildsource, is working to address the challenge of seaweed stabilization through drying. The project combines Blue Evolution's expertise in seaweed processing with Wildsource's seafood processing knowledge to optimize drying conditions and introduce high-quality seaweed products to the market. This innovative approach not only promises to enhance local economic development and job creation but also ensures sustainable seaweed production, paving the way for a new era in ocean crop cultivation.