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176                              A. Reale et al.

              ago. The bottom longline is used very often (63%), because in the MPA the sea bottom is
              rich with Posidonia oceanica, and there are areas of rocky substratum that are conducive for
              this activity.
                Considering these local traditional gears, the species Scorpaena porcus, Scorpaena scrofa,
              Palinurus elephas, and Sepia officinalis were found to be the most representative and with the
              greatest commercial value.
                Table 1 shows the approximate chemical composition (% w/w of raw material) of the four
              species considered, regardless of the catch month as, from the analysis of the variance of
              the data, no statistically significant differences (P> 0.05) were found between the June and
              July samples of the same species. Considering the different species, ANOVA showed that
              P. elephas had the highest (P< 0.05) ash content, whereas the lipid amount was found to be
              significantly higher for S. officinalis and lower for S. scrofa and S. porcus. All species showed
              the same (P> 0.05) moisture (mean value 79.22%) and protein content (mean value 18.15%).
                The protein content of Scorpaena porcus and Scorpaena scrofa from the Egadi Islands
              is similar to that reported for these species caught in different areas [16] but was found to
              be higher than the protein content of species considered valuable, such as cod, dentex, or
              sole. However, Palinurus elephas and Sepia officinalis had a protein content higher than other
              specimens of the same species harvested in different areas [17].
  Downloaded At: 20:22 7 January 2011  enrichment of fat compared with samples of the same species from different origins [17–19].
                Regarding the fat content, all the values obtained were less than 3%, so the species analysed
              can be considered lean. However, it is interesting to note how all the samples showed an

                Tables 2 and 3 list the fatty acid percentage distribution (% w/w of total fatty acids) and
              sum of saturated, monounsaturated, and polyunsaturated acids for the species analysed and,
              within each species, for samples caught in June and July, respectively.
                The analysis of the variance of the data in tables 2 and 3 emphasized that for each species,
              samples caught in different months showed similar fatty-acid profiles. In fact, only a few
              fatty acids present at very low percentages showed any significant differences (P< 0.05)
              between the June and July samples, whereas the most abundant fatty acids and the sums of
              saturated, monounsaturated, and polyunsaturated fatty acids were not significantly different
              (P> 0.05).
                Among the different species, statistical significant differences were observed for almost
              all the fatty acids excluding stearic acid (C18:0) and DHA (C22:6 n3). Considering the
              most abundant fatty acids, palmitic acid (C16:0) showed the lowest level (P< 0.05) for
              Palinurus elephas, whereas same levels (P> 0.05) for Sepia officinalis, Scorpaena scrofa
              and Scorpaena porcus.
                Oleic acid (C18:1 n9), the most representative of monounsaturated fatty acids, was found to
              be statistically higher in Scorpaena scrofa samples and lower in Sepia officinalis samples; this
              acid has particular importance in human feeding for the stimulation of bile secretion, which
              is necessary for digestion and absorption of fats.

                            Table 1.  Proximate chemical composition (% w/w of row material).

                                 Palinurus elephas  Sepia officinalis  Scorpaena scrofa  Scorpaena porcus
                Moisture          78.45 ± 0.62  78.68 ± 0.54  79.82 ± 0.54  79.93 ± 0.57
                Ash                2.18 ± 0.04b  1.51 ± 0.28a  1.29 ± 0.04a  1.42 ± 0.09a
                Protein           18.11 ± 0.58  18.32 ± 0.35  18.39 ± 0.47  17.78 ± 1.07
                Total lipid (M ± S.D.)  1.91 ± 0.09ab  2.38 ± 0.39b  0.68 ± 0.10a  0.80 ± 0.16a

                Note: Values in the same row with different letters are significantly different (P< 0.05).
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