Why are Brazilian deep-demersal fish resources valuable?: An analysis of the size of edible flesh and its chemical composition
Author
Musoles,María Jesús Martínez
Perez,José Angel Alvarez
Pessatti,Marcos
Bova,Michelli Loyola Twardowsky
Abstract
Slope trawl fisheries of the southeastern and southern region off Brazil operate at 250-500 m depths, being basically sustained by three target-species: hake (Merluccius hubbsi), codling (Urophycis mystacea) and monkfish (Lophius gastrophysus), together with other high-priced species landed as incidental captures. These and all other species landed by the slope trawl fleet were sampled from commercial catches, differentiating between shelf/shelf-break species and slope species. Each species was characterized by ex-vessel price, carcass yield and chemical composition: water content and protein content as percentage of wet and dry mass. The differences found in the chemical composition of the slope species, relative to the shallower group, seemed to reflect adaptations for particular environmental factors; most likely low light levels in deeper areas. Their muscles were richer in water and lower in protein and lipids. Ex-vessel prices correlated better with these characteristics than with the edible fraction, revealing that slope fishes exploited off Brazil are appreciated more by their organoleptic characteristics, given by the chemical composition, than by the per-unit profit of the species.