Investigation on the meat yield and chemical quality of crayfish (Astacus leptodactylus esch., 1823) in Keban Dam Lake

IV SUMMARY Master Thesis INVESTIGATION ON THE MEAT YIELD AND CHEMICAL QUALITY OF CRAYFISH (Astacus leptodactylm ESCH., 1823 ) IN KEBAN DAM LAKE Ayşe GÜREL Fırat University Graduate School of Natural and Applied Sciences Department of Fish Catching Technique and Fish Processing Technology 1998, Page: 60 In this study, meat yield and chemical quality Astacus leptodactylus caught in Keban Dam Lake were investigated. The study was carried out between October 1996 and September 1997. A total of 282 crayfish ( 147 females, 135 males ) were used in this study. Annual mean meat yield in Astacus leptodactylus 17.49 ± 3.7 % in female and 18.33 ± 2.3 % in male. The tail meat yield of both female and male crayfish were found to be higher than cheliped meat yield. Chemical analyses showed that female crayfish had 79.53 ± 1.5 % moisture, 16.74 ± 1.81 % protein, 0.45 ± 0.14 % fat, 1.29 ± 0.25 % ash and 2.06 ± 0.59 % carbonhydrate in their tail meat. These values in cheliped meat of female crayfish were 79.6 ± 1.45 %, 16.8 ±1.77 %, 0.4 ±0.11 %, 1.31 ± 0.21 % and 1.86 ±0.7% respectively. Tail meat of male crayfish had 79.7 ± 1.45 % moisture, 16.44 ± 1.71 % protein, 0.49 ± 0.25 % fat, 1.37 ± 0.33 ash and 2.03 ± 0.67 % carbonhydrate. These values in cheliped meat of male crayfish were 78.99 ± 1.25 %, 17.1 1 ± 1.45 %, 0.5 ± 0.18 %, 1.51 ± 0.42 % and 1.90 ± 0.56 % respectively. According to annual mean values, tail meat protein of male crayfish were found to be higher ( p<0.05 ) than in their cheliped meat. Ash values of cheliped meat of female crayfish were found to be less ( p<0.05 ) than in cheliped meat of male crayfish. Apart from above values no differrences were determined between male and female crayfish. pH values in tail meat of both male and female crayfish were less ( p<0.05 ) than in their cheliped meat. In conclusion, it was determined that meat yield and chemical composition of crayfish samples examined were relatively in good quality. KEY WORDS: Astacus leptodactylus, Meat Yield, Moisture, Protein, Fat, Ash, Carbonhydrate, pH.