Krill meal is produced from Antarctic krill (Euphausia superba) found in the Southern Ocean around the frozen continent. Krill survive their first winter living in the water column on the underside of sea ice where they harvest the microscopic algae that grows there. Adult krill are shrimp-like in appearance, but, in contrast to their bottom-dwelling crustacean relatives, the shrimp, krill inhabit the open ocean. Here, krill aggregate in swarms of up to twenty kilometers in length where they feed on microscopic algae during the day and migrate to greater depth during the night as to evade predators.

Krill appear transparent with some red and green coloration. The red is caused by the carotenoid pigment astaxanthin embedded in chromatophores. The crustacean can change the size and intensity of the red spots in order to balance the need of UV protection closer to the ocean surface with higher transparency for camouflage. The green is observed in their digestive system and underscores their reliance on an algal diet. In fact, krill can consume up to 20% of their own body weight per day but can also survive for up to 200 days without food. During the Antarctic summers, when photosynthetic algae bloom, the sheer abundance of krill makes it one of the largest protein sources on Earth - a source eagerly sought by fish, whales, and men alike.

This special crustacean holds a vital position in the marine food chain.