textured They’re arrayed in multiple layers, and greatly reinforced with strengthening and toughening connective-tissue collagen, some three to five times more than fish muscle has Unlike the fragile collagen of fish, squid and octopus collagen is extensively cross-linked and behaves more like the collagen of meat animals Like the abalone and clam, squid and octopus must be cooked either barely and briefly to prevent the muscle fibers from toughening, or for a long time to break down the collagen Cooked quickly to 130– 135ºF/55–57ºC, their flesh is moist and almost crisp At 140ºF/60ºC it curls and shrinks as the collagen layers contract and squeeze moisture from the muscle fibers Continued gentle simmering for an hour or more will dissolve the tough, contracted collagen into gelatin and give the flesh a silken succulence Pounding can also help disorganize and thus tenderize mantles and arms Cephalopod Flavor and Ink Like finfish, squid and octopus maintain their osmotic balance largely with the tasteless TMAO (p 188) rather than with free amino acids Their flesh is therefore less sweet and savory than that of the other molluscs, and can turn fishy when bacteria convert TMAO to TMA Cephalopod ink is a bag of pigment that the animal can squirt into the water when endangered It’s a heat-stable mix of phenolic compounds (animal cousins of the phenolic complexes that discolor cut fruits and vegetables; p 269), and cooks use it to color stews and pastas a dark brown Other Invertebrates: Sea Urchins Spiny sea urchins are members of the animal group called echinoderms (Greek for “prickly skin”), which may account for 90% of the biomass on deep-sea floors There are about a ... Flavor and Ink Like finfish, squid and octopus maintain their osmotic balance largely with the tasteless TMAO (p 188) rather than with free amino acids Their flesh is therefore less sweet and savory... sweet and savory than that of the other molluscs, and can turn fishy when bacteria convert TMAO to TMA Cephalopod ink is a bag of pigment that the animal can squirt into the water when endangered... It’s a heat-stable mix of phenolic compounds (animal cousins of the phenolic complexes that discolor cut fruits and vegetables; p 269), and cooks use it to color stews and pastas a dark brown Other Invertebrates: