accessible brisling bristling calcium can canned clupeidae crammed edible European-sprat fatty-acids fish food health healthy heart-healthy herring-family herring-like marine-fish nonperishable nutrient-rich nutrients nutritious oil oily-fish omega-3 open opened packed pilchards portable potential sardines self-contained-food silvery skin skipper small sprat sprattus-sprattus tight tightly-packed tin tinned tins vitamins