Comparative Characteristics of Physicochemical Parameters of Meat and Biochemical Composition of Hemolymph in Three Species of Crayfish

Background. Crayfish farming is a promising direction in the development of aquaculture. Compared with marine crustacean species, freshwater crayfish require lower cultivation costs, while their meat is regarded as an additive dietary delicacy with a high nutritional value. The aim of this study was to compare the morphological and physiological data (slaughter yield, taste quality, physicochemical composition of meat, and some biochemical indexes of hemolymph) of three species of adult crayfishes, i.e. Australian red claw crayfish (Cherax quadricarinatus), narrow-clawed crayfish (Astacus leptodactylus), and marbled crayfish (Procambarus fallax forma virginalis), which were cultivated in a recirculating aquaculture system.

Materials and Methods. Organoleptic and physicochemical methods were used to assess meat quality, while biochemical methods were applied to determine hemolymph parameters in the abovementioned crayfish species.

Results. The results showed that the edible portion relative to live weight was 15.16 ± 0.20 % in the Australian redclaw crayfish, 12.16 ± 0,21 % in the Marbled crayfish, and 9.40 ± 0,19 % in the Narrow-clawed crayfish. The highest protein content in meat was observed in marbled crayfish (17.4 ± 0.84 %). The highest fat content was registered in Australian redclaw crayfish (0.95 ± 0.024 %); for the marble crayfish, this value was 0.9 ± 0.03 %, and for the narrow-clawed crayfish, it was 0.9 ± 0.35 %. No differences were found in carbohydrate content among the studied species; the value of this parameter was approximately 1.2 ± 0.02 % in all the crayfish species. The meat of Australian redclaw crayfish exhibited the highest energy value (76.1 ± 3.12 kcal/100 g), exceeding that of the other species by 1.3 – 2.2 kcal/100 g, marbled crayfish – 74.8 ± 3.69 kcal/100 g, and narrow-clawed crayfish ‒ 73.9 ± 3.52 kcal/100 g, respectively. In terms of hemolymph protein content, Australian redclaw crayfish showed the highest level (77.1 ± 2.87 g/L), for the narrow-clawed crayfish, this value was (64.9 ± 2.90 g/L), and for the marbled crayfish, it was (57.2 ± 2.41 g/L).

The highest calcium concentration in hemolymph was observed in narrow-clawed crayfish (9.52 ± 0.212 mmol/L), while comparable levels were recorded in Australian redclaw (7.99 ± 0.215 mmol/L) and marbled crayfish (7.42 ± 0.292 mmol/L). Differences in all studied indicators were considered statistically significant at p ≤ 0.05.

Conclusions. The study results obtained for Australian red claw crayfish, narrow-clawed crayfish and marbled crayfish allow us to evaluate their productivity and meat nutritional validity, as well as to propose the reference ranges of key indexes which can be used in optimizing aquaculture technologies and production of high-quality delicacies or supporting food products.