No animal part to waste: tuna ranchers join circular revolution

Waste not, want not – not the proverb always suited for the Maltese bluefin tuna ranching industry, an exploitative business often blamed for hastening the overfishing of tuna stocks destined for the Japanese food market.

But in Ħal Far, on an industrial wasteland looking to the south of the Mediterranean, the main players in this multi-million export business are joining the circular economy – the business of reusing goods to create a sustainable lifecycle for the industry.

To critics of tuna ranching, the brand new €12 million factory that turns tuna offal, heads and fins into fishmeal and high-quality oil might be a dull, silver lining for an activity whose success is dependent on industrialised fishing – one that also turned artisanal fisherman into powerless spectators of the large purse seiners and tuna ranches.

But as Charlon Gouder, the CEO of Aquaculture Resources Limited, says, the industry has finally managed to recover a not-so-insignificant waste resource to be turned into a high-quality export commodity.

“It’s hard to believe but, until now, almost 25% of the total amount of fish was being discarded as waste. This was of huge economic and environmental concern. It made little economic sense. That one statistic puts the importance of this facility into perspective,” he says at ARL’s new processing plant, where Danish technicians are currently commissioning the factory’s machines.

It is, to put in lazy layman’s terms, one giant fish broth – tuna heads, gills, fins... freshly caught the previous day, are being taken out of the freezer trucks, as forklift trucks raise plastic containers into a giant grinder. It is incredible to see the huge quantity of tuna meat, still edible, clinging to the severed heads of these noble 200kg beasts, that would otherwise be treated as ‘waste’ – traditionally dumped back into the sea under strict environmental permit conditions – and now being turned into an edible product as fish-meal for pet foods and nutraceutical products, with potential for further human use.

The blood trickles off the container as the giant head stocks and dorsal fins are dumped into a series of machines – a hopper, a breaker, then a Lamella pump – that will generate a fine granular raw material of tuna meat. Immediately, the container tubs are placed into a covered €600,000 power-wash system that also air-dries the tubs, then robotically stacks them up for re-use. It is an impressive feat of quasi-automation that allows minimal wastage – the water is diverted instantly to a waste-water treatment plant on-site – with no odours from the frozen tuna. The days here will end with a daily, three-hour cleansing operation for the entire ‘wet’ portion of this plant.

The granulated raw material now enters a second phase of separation, with a centrifugal force separating the solids from its oils. While the oils are diverted to their final containers the solids are transport to a massive disc-dryer – the centrepiece ‘oven’ in this plant – which moves these solids slowly from one end to the other, where they are gently steamed and cooked.

Even the resultant water from this process gets turned into a demi-glace treated in pretty much the same way as a fish-stock, the water being allowed to evaporate, so that the resultant protein gets added to the solids inside the disc-dryer. “We’re using the raw material entirely,” says ARL’s technical consultant Tristan Camilleri, proud to explain how five tonnes of raw material will be processed at each hour, to produce an annual output of 450 tonnes in fish meal, and 550 tonnes of oil each year – conservatively valued at €3 million in exports. “This is high-value oil. We are getting high yields, with huge Omega values, and producing best-in-industry quality fishmeal,” he says, handing me the bottarga-like dust of tuna granules.

It is not an operation that is without problems: the prohibitive cost of the plant’s daily operations presents challenges of how to ensure the fledgling plant can achieve full operational activity once the tuna harvesting season – running from September to January – passes. “We hope we can attract fish waste exports to Malta,” Gouder says of the plant, which charges tuna ranchers a gate fee to dispose of their tuna waste.

The costs of achieving full circular activity are also evident in the plant’s air processing system and its waste-water treatment area. Outside the plant, the faint whiff of this ‘tuna aljotta’ is evident, but inside it is relatively odourless for what is essentially a giant pot of broth. The air quality inside is ensured because individual airflow systems capture the steam generated by all the engines. This ‘heavily polluted air’ from the tuna cooking process, gets sucked into an overhead air treatment system, which filters the air before it emerges into the environment.

Even the waste-water system – a micro-version of similar treatment plants I visited in Gozo – is treating the effluent before its draining into the national sewage system. These relatively odourless treatment systems complement the inherent ‘circularity’ of the ARL plant.

ARL, which is owned by ranching giants AJD Tuna, Fish And Fish and MFF Limited, is the showcase of Malta’s tuna lobby, the Maltese Federation of Aquaculture Producers. Now it hopes it can use its sprawling 3,000sq.m land to a business incubation centre focusing on the aquaculture and marine industry, for scientific researchers.

Gouder says that upgrades to the ‘polishing’ of the final product means that the fish-meal and oils could be further used for human consumption or cosmetics. “In other words, more good ideas are welcome and can be tested. The industry may not know what the future holds, but it is ready to embrace change and adapt as the world of commerce changes.”

As a major exporter, aquaculture’s contribution to the Maltese economy remains significant. In 2021 an increase in tuna quotas led to an almost 15% increase of bluefin tuna, generating €25 million more in Maltese domestic output, above the €179 million registered in 2020. Today Malta is one of the largest producers of bluefin tuna in the Mediterranean and Atlantic, and the top producer in the European Union. One of its main markets is Japan. “Ask a Japanese person what their view of Maltese tuna is and they will tell you it is the best, the very hallmark of good quality,” Gouder says.

The industrial turn

Initially tuna was fished using the tunnara artisanal trap system, and after the 1960s using hook-and-line methods such as long-line gear. But it was during the 1990s that the international demand for toro meat – tuna belly, prized in Japan for sashimi and sushi – led to an increase in Maltese exports to the international market.

Industrialised methods allowed fishing companies like Ricardo Fuentes to capture enormous numbers of tuna using purse seiners, to provide enough live bluefin tuna to stock ranches with hundreds of tonnes of tuna from just one trip. While industrial giants used technology to detect areas where the fish are, traditional fishers catch one fish at a time and are led to their prey by seagulls.

Overfishing and exploitation soon gave way to ‘tuna wars’, as competition for the species became intense. It was this rapid growth that brought enormous stress on tuna resources from overfishing. Calls for quotas, imposed by the International Commission for the Conservation of Atlantic Tunas (ICCAT), eventually led to the introduction of the total allowable catch (TAC). TACs brought a drastic overhaul of fishermen’s lives. When governments decided to reduce tuna fleet capacities by 25%, smaller fisherman cashed out their quotas to the big players.

Charlon Gouder, who defends the industry’s record in abiding by strict regulations, says today Malta’s tuna federation holds the highest of standards and sees sustainability as part of its make-up.

“Employees are trained to collect slime, keep all marine installations clean and free of rubbish and flotsam, source baitfish of the highest quality, and ensure that whenever boats are at a loading bay, with bait fish on board, they are equipped with booms to ensure the capture of any slime that is lost.

“The industry is subject to checks by independent inspectors which the Federation welcomes because it wants its solid record to be recognised.

“We’re rightly proud of what we have achieved, especially the new facility at Ħal Far – we’re determined to make waves in the future too.”