Determination of proximate composition and fatty acid profiles of Astacus leptodactylus Eschscholtz, 1823 in Turkish freshwater resources

Abstract

This research was conducted to evaluate the nutrient content ofAstacus leptodactylusin various populations in the lakes Iznik and Egirdir, as well as in Hirfanlı Dam Lake and Keban Dam Lake, all in Turkey. Crayfish meat yield ranged from a minimum of 11.3% to a maximum of 16.3% of wet weight in specimens from Keban and Iznik, respectively. Meat yield was significantly different, depending on the living environment. The protein content of the meat ofA. leptodactylusranged from 15.4 to 17.5%. The moisture content of crayfish was significantly lower in the high lipid containing Iznik Lake’s crayfish. Crayfish lipids were poor in saturated fatty acids, but rich in PUFA’s and in particular EPA, DHA and ARA. In all groups, the major saturated fatty acids were palmitic acid, stearic acid and myristic acid. Among the omega-6 fatty acid series, a high level of ARA was observed in crayfish meat.EPA may be considered as the major omega-3 fatty acid in crayfish lipids. There was no single fatty acid indicating regional differences in crayfish specimens.

Interactions of season, sex and size on nutrient composition of freshwater crayfish (Astacus leptodactylus Eschscholtz, 1823) from Lake Eğirdir

“…Similarly, Stanek et al (2013) indicated no differences between sexes in ∑PUFA contents, however ∑PUFA contents were found similar between spring and summer. Harlioğlu et al (2012) and Dksuz & Mazlum (2016) determined higher ∑PUFA (45.97%, 53.52% respectively) than ∑SFA and ∑MUFA. Also, they detected higher ∑PUFA contents than that of the present study in tail muscle of A. leptodacylus.…”

“…The cause of this situation may be species and habitat differences. Similarly, Dksuz & Mazlum (2016) determined SFA content as 21.32% in tail muscle A. leptodactylus caught from Egirdir Lake. Harlioğlu et al (2012) reported SFA content as 25.56% in tail muscle of A. leptodactylus caught from Lake Keban Dam.…”

“…There are different reports in terms of crude lipid contents tail meat of A. leptodactylus; 0.57% (Harlioğlu et al, 2012), 1.25% (Dksuz & Mazlum 2016). Bilgin et al (2008) reported the highest lipid content was 1.91% and the lowest lipid content was 1.09% in different size female crayfish.…”

“…Harlioğlu et al (2012) detected ∑MUFA content as 28.17% in tail muscle of A. leptodacylus. Dksuz & Mazlum (2016) indicated as 24.60% ∑MUFA content in tail muscle of A. leptodacylus. Contrary to our results, ∑MUFA contents were high in previous studies.…”

“…Onanlı & Çoban (2007) and Bilgin et al, (2008) did not determine difference between sexes in terms of protein contents in tail meat of A.leptodactylus. The protein contents in tail meat of A. leptodactylus were determined as 15.98% male and 16.39% female in (Onanlı & Çoban 2007), 14.61% in (Harlioğlu et al, 2012), 16.32% in (Çoban et al, 2012), in 15.23-16.66% in (Duman et al, 2012), male (15.68%) and female (17.59%) in (Berber et al, 2014), 15.41% in (Dksuz & Mazlum 2016). The reason of differences in protein contents in these studies can be habitat different, environmental factors and nutrient availability (Winberg, 1956).…”