Some of the nutritional properties of Potamon potamios, captured from the Lake of Egirdir were investigated in relation to season and sex. In the laboratory, crab meat and crab shells were seperated. All crab meat and dried crab shell analyses were conducted separately. According to proximate composition analysis, there were no significant differences in the moisture, protein, fat and ash contents in terms of seasons. But there were significant (P<0.05) changes between male and female crab meats in terms of protein values. It was found that freshwater crab meat was a good protein source. Mineral matter analysis was carried out with ICP-OES instrument after drying of crab samples in lyoflizator. Of the crab meat, the highest contents of calcium, sodium and potassium were 17.87±1.356 (winter ♀), 11.88±0.62 (summer ♀) and 11.70±0.50 mg/g (summer ♂) while these values for crab shell were 197.50±7.836 (summer ♂), 3.96±0.583mg/g (winter ♂) and 6.26±0.222mg/g (summer ♂), respectively. Chitin and Chitosan analysis were performed from shells with demineralization, deproteinisation, decoloration and deacetylation. Female freshwater crab samples had the highest chitin (7.80±0.835%) and chitosan (5.86±0,536%) contents in the summer and spring, respectively.

Key words: Chitin; Chitosan; Mineral;  Potamon potamios; Food composition; Season