Mussels in pet food help climate, wildlife and communities

In addition to the social and environmental sustainability aspects, mussels provide the important omega-3 fatty acids, DHA and EPA, which support dog and cat brains, hearts and other aspects of health.

NOTE: Rheintek Latinoamerica and Kemin Industries sponsored Petfood Industry's trip to visit the Landes Seafood plant in Chile. The companies provided Petfood Industry's reporter with room, board and transportation.

Along the coast of the Chiloé archipelago in Chile, sea lions swim among native mussels (Mitylus chilensis) clinging to ropes dangling into the cold waters of the Pacific Ocean. Seagulls squawk overhead, and cormorants bob through the waves.

These Chilean native mussel farms meet many of the criteria pet owners increasingly demand for sustainable ingredients used in their dogs’ and cats’ diets. The diversity of wildlife flourishing around these mussel farms stands in contrast to the ecological monotony of a conventional cattle feedlot or poultry barn. Likewise, raising mussels requires fewer resources than most livestock or fish. The main byproduct of mussel farming, empty shells, may fight climate change by locking up carbon. Chilean mussel farms also provide work for local communities with Indigenous heritage.

Along with Chilean varieties, various mussel species appear in dog and cat foods or treats featured in Petfood Industry's Product Database. These products include functional joint and mobility pet food formulations, as well as treats and supplements.

Mussel farms require few inputs from those who raise them, Germán Naranjo, commercial manager for Landes Seafoods, told Petfood Industry during a tour of the company's facility in Dalcahue, Los Lagos, Chile. Aquaculturists collect mussels' free-swimming larval phases from freshwater streams and rivers in specialized nets. The mussel farmers release the larvae onto large ropes, upon which the mussels attach themselves. These ropes dangle in the ocean and the bivalve animals continue their lifecycles. Since mussel production uses only sea water, it doesn't compete for fresh water as cows, pigs and poultry do. Mussels are filter feeders, pulling in plankton and other tiny organisms from the ocean. As they do, the mussels clean the water and may even reduce pollution from salmon farms if located nearby, as Maureen Mahoney, corporate sourcing manager at Simmons Foods, pointed out during the tour.

Once they have reached an appropriate size, the farmers pull up the ropes using winches attached to barges. The harvested mussels go to a processing plant where workers and machines detach them from their ropes. An automated line conveys these mussels to be rapidly cooked then frozen. The process from fresh to cooked to frozen takes less than 30 minutes. The cooked mussels pop out of their shells. The machines separate and collect the shells, which are used as fertilizer.

This shell-based fertilizer adds another environmental benefit to mussel farming. Mussels construct their shells from calcium carbonate, using carbon dioxide dissolved in the ocean. By pulling that carbon from the sea, the mussels reduce oceanic acidification and fight climate change.

Scientists with the Council for Agricultural Research and Economics Research Centre for Animal Production and Aquaculture documented how mussel farms can serve as a carbon sink. Raising mussels ends up pulling more greenhouse gases from the environment than it releases. They published their results in the journal Science of the Total Environment. Other studies, published in the Journal of Cleaner Production and the journal Renewable and Sustainable Energy Reviews, have corroborated the potential of mussel farms as carbon sinks.

When they are harvested, the mussels bring the carbon they used to build their shells with them. Other carbon sequestration methods, like planting trees, can also fight climate change. However, few other protein production methods directly reduce greenhouse gas pollution and ocean acidification.

Along with supporting ecosystems, these Chilean mussel farms support local communities, many with indigenous Mapuche heritage. During the pandemic, Landes continued to support these communities despite movement restrictions and plant closures. During the normal season, the Landes Seafood plant supports approximately 220 workers, as it processes 10 to 12 tons of mussels per hour. Each day, the facility produces 50 tons of finished product from November to July or August. The mussel industry is the second-largest source of income for the Chiloé Archipelago, after salmon and before tourism. That income spreads out through the community, supporting numerous small businesses.

In addition to the social and environmental sustainability aspects, mussels provide the important omega-3 fatty acids, DHA and EPA, which support dog and cat brains, hearts and other aspects of health. Beyond what mussels provide, what they take away may be just as important. As the mollusks build their shells, they absorb carbon from the ocean. While people placed the mussel farms, the presence of the mussels is natural and helps to maintain the ecosystem that feeds sea lions, birds and other wildlife. The mussels filter the water and can help control wastes from salmon farms or other contaminants.