Temperate seaweed markets, an overview (part 1: a look back)

Production declined, but demand grew. The imbalance caused prices to spike.

Read anything recent on the development of the global seaweed market, and you’d come away thinking that this sector is booming, with articles in both the popular and academic press citing increasing production numbers and growing demand, leading to claims like “seaweed is the world’s fastest growing food production sector“.

After reviewing the data, this overview of the temperate seaweed industry in 2024 finds no proof for that narrative. It’s not growing fast, it’s not growing at all. It’s in decline.

Demand has been growing, though, that’s true. While trends in seaweed markets have been uneven, overall we can observe continued demand growth for the most popular temperate seaweed species. However, production data shows a decline since 2020. Declining supply coupled with strong demand is leading to price hikes, particularly in food markets. Beyond food, let’s examine trends in feed, biostimulants, alginates, personal care and ecosystem services markets for seaweeds that grow in cold and temperate waters.

A. Demand

Three temperate seaweed markets have seen strong growth in recent years: South Korean gim, biostimulants and abalone feed. The alginates market grew as well, but at a lower pace. 

*estimated; **2016-2021

1. Gim exports

In 2016, the value of South Korea’s exports of gim (or laver in English, nori in Japanese, Pyropia yezoensis in Latin) stood at 353 million. In 2023, the nation’s gim exports totaled $771 million, representing an average 11.8% year-on-year growth in the seven-year period. Largest markets in 2023 were the USA at $169 million, China at $144 million, Japan at $97 million, Thailand at $66 million and Russia at $57 million.

2. Biostimulants

The global seaweed extracts biostimulant market was estimated at $535 million for 2016. According to The Nature Conservancy and Bain, the seaweed biostimulants market was worth around $1 billion in 2023, implying a yearly growth rate of 9.3% in the past seven years. While tropical seaweeds have taken a share of this market in recent years, the vast majority of products sold remain based on temperate seaweeds. 

3. Abalone feed

Farmed abalone production grew from 156,875 tons in 2016-2017 to 243,506 tons in 2020-2021. Abalone are generally fed a mixture of temperate-water seaweeds, some of which is grown on farms at nearby locations, while the rest is sourced from wild stands or algal blooms. As such, abalone aquaculture has boosted seaweed production. However, due to the self-contained nature of the trade, with many farms cultivating both abalone and the seaweeds to feed them, an estimate on market value is not available.

4. Alginates

In 2016, global alginate production totaled 48,144 tons according to Porse & Rudolph. In 2023, insiders estimate global alginate production at 55,000 tons, implying a compound annual growth rate of 1.6%. This is lower than the estimate of hydrocolloids research firm IMR, which puts the growth rate at 2.5-3%. Sausage casings have been a strong growth market in recent years. Due to improved processing technology, alginate sausage casings now offer considerable cost and efficiency savings compared to incumbent hog, sheep, collagen or cellulose casings. The growth of plant-based and halal markets are additional drivers of demand. 

The market for alginate-based acid reflux medicine is also growing. Previously confined to Europe, pioneering remedy Gaviscon has seen increased uptake in the United States. Competitors have sprung up and found success too. The market for alginate-based dental molds is likely in decline due to the advent of digital imaging. For the size and growth trajectory of other alginate markets like textile printing paste, wound dressings and various food applications, no reliable numbers were found. 

5. Food

Trends in food markets for temperate seaweeds vary by country. Japanese seaweed consumption has nearly halved in 20 years, from 4.0 grams per person per day in 2002 to 2.1 grams per person per day in 2022, an annual decline of 3.2%. This is in line with the trend in Japanese fish and shellfish consumption, which also saw a decline close to 50% this century, from 40.2 kilograms per capita in 2001 to 22 kilograms in 2023. High prices, a desire for convenience and a diversification of the Japanese diet towards more meat and foreign cuisines are the main reasons cited for the long-term decline.

In Korea, daily seaweed consumption remained stable: in 2014, 3.3 g of seaweeds were consumed per person per day. In 2022, this had risen slightly to 3.4 g per person per day. In China, increasing urbanization and consumers’ growing nutritional knowledge drove growth in seaweed consumption in the first decade of the century, when total seaweed consumption increased from approximately 2 g per person per day in 2004 to 3.1 g per person per day in 2009. No reliable data was found for the evolution in the past 15 years.

In Europe and North America, the consumption of algae remains limited but is experiencing a growing trend due to increases in product availability and positive media attention. However, a lack of data regarding availability and consumption prevents accurate statements about market size and growth trends. 

One notable feature of Western seaweed food markets is the contrast between high demand and insufficient supply of dulse (Palmaria palmata), and low demand and oversupply for sugar kelp (Saccharina latissima). The increasing demand for dulse, primarily from food manufacturers, exceeds the current production based primarily on wild-harvested biomass, leading to high prices. According to Stévant et al., the wholesale value of dried dulse was 16-19 €/kg ten years ago, now 40-75 € per kg (20-37$ per pound). To compare, cultivated kelps sell wholesale for 2-4 €/kg. The current median retail price of dried dulse is 134€ per kilogram (66$ per pound).

6. Cosmetics and personal care

Seaweed extracts for use in cosmetics and personal care products could be a source of significant value. However, extracts tend to be sourced from small, specialized firms before formulation by bigger brands, which makes it difficult to gauge market size. Indicators of market growth are not consistently pointing in the same direction: Setalg, a subsidiary of agribusiness conglomerate Groupe Roullier specializing in seaweed-based cosmetics, closed its doors in 2024 due to a lack of profitability. In the same year, Australia’s Marinova, a provider of fucoidans mostly for personal care brands, expanded its production capacity.  

7. Emerging markets

Emerging markets, including nutraceuticals, biomaterials, feed and pet food supplements, methane-reducing feed additives, specialty chemicals and bioremediation are still nascent and for now too small to estimate. 

B. Supply

Harvests of 3 main temperate seaweed species in top producing countries in wet tonnes (according to FAO numbers) 

Calculating the yearly growth rate (CAGR) based on those numbers…

*calculated from 2003 when statistics started

Saccharina spp. (sugar kelp)

According to FAO data, cultivation of Saccharina japonica in China grew at a yearly rate of 4.1 percent between 2000 and 2020, from 4.9 million tonnes to 11.2 million tonnes wet weight. 

While the exact size of China’s production is sometimes called into question, the fact that the industry underwent strong growth is undeniable. However, recent events indicate that this rapid expansion has now hit a bottleneck. 

According to Hu et al., in 2022, around 440,000 tonnes (dry weight) of S. japonica in Shandong bleached and decayed owing to environmental fluctuations, most likely due to a breeding-induced, biased allocation of energy resources. Kelp breeding systems in China have encountered problems relating to germplasm diversity, regulation and technological innovation. In combination with the pressures of warming waters and ocean acidification, this has led to production decline.

In South Korea harvest numbers exhibit a similar pattern. Cultivation of S. japonica expanded massively for two decades, but declined after 2020. In Japan, the decline started earlier and has been more gradual. The price of kombu reached a high of 1,620 yen (11.4$) per kilogram in Japan in 2024 after another bad harvest blamed on rising ocean temperatures.

In Europe and North America, the cultivation of Saccharina latissima was initiated around 15 years ago. While kelp farming is now established with dozens of small-scale farms operating across North America and northwestern Europe, volumes have remained limited, with a lack of demand seen as the major impediment to greater production volumes. In the United States, around 600 tonnes of seaweeds were harvested in Maine in 2024. In Alaska, harvests decreased from nearly 400 tonnes in 2022 to somewhere around 100 tonnes in 2024. Norway harvested 600 tonnes in 2023. Leading companies in France and the Faroe Islands harvested 200 and 240 tonnes of seaweeds respectively in 2023. In each location, the majority of seaweeds were S. latissima. 

To sum up: in Asia, the cultivation of Saccharina spp. is in decline due to pollution, climate change and past kelp breeding strategies coupled with a lack of timely innovation. The production shortfall is leading to price spikes. In the meantime, the opposite is true in Europe and North America: production is at overcapacity, but expansion is hampered by a lack of processing infrastructure and product-market fit. 

Pyropia yezoensis (nori) and Undaria pinnitifida (wakame)

While production numbers for P. yezoensis show a similar pattern to those for S. japonica for the first two decades of the new millennium, the picture is less marked beyond 2020. In sum, the production of P. yezoensis by the three biggest producers has seen a slow decline of 1.4 percent annually from 2020 to 2022, from 3,045,903 tonnes to 2,959,201 tonnes. In combination with the strong increase in demand from international markets, this has led to dramatic price spikes.

Harvest numbers for U. pinnitifida exhibit the same trend as P. yezoensis: after 2020, growth turned to decline for China, decline accelerated in Japan, while South Korea managed to continue to expand production. Although the total decline is less pronounced compared to P. yezoensis and S. japonica, here too Japanese consumers have been hit by price hikes, with the average price of boiled wakame reaching 2,479 yen ($16) per kilogram in 2024, up 54% from last year.