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The organic farming of sea bass and sea bream was investigated in a commercial farm by assessing environmental impact, growth performance, fish welfare and product quality in a multidisciplinary approach. Organic and conventional juveniles were reared in four circular 3.800 m 3 floating sea cages at a maximum final stocking density of 15 kg/m 3 and fed on organic or conventional commercial feeds. Conventional farming was started simultaneously and monitored as the reference condition. Environmental and biological samplings were performed after 16 months at the first fish harvesting. No environmental impact was observed in the organic farming area, whereas a significant increase in total phosphorus concentration in the sediment and some changes in the structure and species composition of benthic assemblages were detected just beneath the conventional sea cages with no impact 25 m from the cages. Organic fish showed a better growth performance consistent with the lower feed conversion ratio and higher metabolic status, as evidenced from the protein and energy profiles, compared with conventional fish. No dietary influence on stress and immune response was observed. A higher incidence of fin splitting occurred, probably due to nutritional factors and/or to the larger size of organic fish. Similar good morphological, physical and sensory traits between organic and conventional fish were observed, as denoted by the high fillet yield, low flesh lipid content, long freshness and shelf life both in sea bream and in sea bass. Conversely, the fillet fatty acid composition was different, being poorer in n-3 PUFA and richer in linoleic acid (C18:2 n-6) in organic versus conventional fish, mirroring the fatty acid profile of the diet. The organic farming of sea bass and sea bream exhibited an overall good performance. Husbandry and feeding practices did not produce any evident environmental impact although long-period investigations covering several full production cycles are needed. Organic fish grew well, displayed an overall state of well-being and had good quality features despite a lower EPA and DHA content. Improvement of organic feed formulation and quality of feed ingredients emerge as important issues to be addressed to optimize the nutritional quality of organic sea bass and sea bream.

Seventeen whitefish species caught in the North Adriatic sea were sampled from the wholesale fish markets of Cesenatico and Rimini from October 2006 to May 2007 to gain a better knowledge of their potential as a source of macro- and micro-elements, both at the raw and cooked state. Flathead grey mullet (Mugil cephalus, 13 batches, 13 specimens on the whole), annular seabream (Diplodus annularis, 3, 19), and conger eel (Conger conger, 8, 8) were destined to pan frying (PF). Striped mullet (Mullus barbatus, 12, 166), picarel (Spicara smaris, 2, 17), bogue (Boops boops, 7, 47), yellow gurnard (Trigla lucerna, 12, 60), largescaled scorpionfish (Scorpaena scrofa, 5, 52), Dover sole (Solea solea, 12, 77), stargazer (Uranoscopus scaber, 4, 20), and greater weever (Trachinus draco, 5, 50) were destined to oven baking in a partially covered baking tin (OB). Red bandfish (Cepola rubescens, 2, 35), common Pandora (Pagellus erythrinus, 5, 50), rock goby (Gobius paganellus, 6, 120), poor cod (Gadus minutus capelanus, 9, 54), blue whiting (Micromesistius poutassou, 12, 114), and European hake (Merluccius merluccius, 14, 85) were intended for cooking in parchment (CP). The content of ten macro- and micro-elements were determined in raw and cooked flesh by ICP-AES. Since each cooked sample had its own proper raw reference, true retention coefficients could be computed for each element. At the raw state and collapsing the effect of the catching season, the whitefish species examined here proved to be well endowed in potassium (especially bogue, European hake, and blue whiting) and selenium (especially conger eel), while being quite poor sources of iron and zinc. Upon cooking, each element underwent an increase in concentration. In terms of true nutrient retention, CP proved to be the most conservative out of the three implemented cooking methods, while PF was the least one.