1. SEPARATION PROCESSES FOR ISOLATION OF UNSATURATED FATTY ACIDS FROM FISH SAMPLES Stefan Kuvendziev* 1, Kiril Lischkov 1, Zoran Zeković 2, Mirko Marinkovski 1 1- Faculty of Technology and Metallurgy, University Ss. Cyril and Methodius, Skopje, Macedonia 2- Faculty of Technology, University of Novi Sad, Novi Sad, Serbia Šesti simpozij„Hranom do zdravlja“ 2013 1

2. Overview  Fish and fish products fit in the modern trends of food processing industry and human nutrition.  Presence of bioactive compounds in the fish tissue.  Conventional and contemporary separation processes for isolation of bioactive compounds from fish samples  Soxhlet extraction or hot continuous percolation  Ultrasound assisted extraction  Supercritical CO 2 extraction  GC-FID analysis (fatty acid profile) 2

3.  The goal of this work is determination of the presence of biological active compounds in fish viscera, caviar and fillet obtained from fresh water carp (Cyprinus carpio L.) from Tikveš Lake, Republic of Macedonia 3 Common carp - Cyprinus carpio L.

4. Chemical composition of common carp 4 TissueTotal proteins (%)Dry matter (%)Ash (%)Ca (%)P (%) Caviar21.8745.51.50.360.07 Fillets16.9341.31.80.350.05 Viscera14.5833.762.10.350.06  Total fats !

5. 5 CONVENTIONAL METHOD FOR OBTAINING FISH OIL RECOVERY AND REFINEMENT OF CRUDE FISH OIL

6. 6 OIL INTO CONCENTRATE

7. 7 REFINEMENT OF CRUDE FISH OIL CONCENTRATE INTO ‘PHARMACEUTICAL GRADE’ OIL

8. Lyophilization  Why?  Water interferes with the extraction processes  Solution: freeze drying (lyophilization) 8  Residual water content in fish viscera, caviar and fillets - less than 2.5%

9. Soxhlet extraction  Soxhlet extraction or hot continuous percolation is a conventional separation technique  Various solvents (different polarities) can be used  Determination of fats (Soxhlet method - AOAC 960.39)  Total extracts up to 79% (w/w) from lyophilized tissues 9

10. Ultrasonic extraction  Ultrasonic extraction is a contemporary separation technique  Extraction was performed using various solvents, at ambiental temperature  Yield of total extracts up to 42% (w/w) from lyophilized tissues 10

11. NON-CONVENTIONAL (ALTERNATIVE) PRECISE PROCESS ECO-TECH METHOD FOR OBTAINING OF FISH OIL 11 ANIMAL (FISH) SAMPLES SCFE-CO 2 ‘ULTRA’ PURE FINAL PRODUCT (FISH OIL)  Supercritical fluid CO 2 extraction is a modern separation technique  Fits in the frames of green technologies  Extracts with high purity  Selective towards unsaturated fatty acids

12. Supercritical fluid CO 2 extraction Operating conditions: o Pressure (200-400 bar) o Temperature (40-60 °C) o Extraction time 3 h o Flow rate 12 FINAL FISH PRODUCTS FISH OIL SFE - CO 2 Yields of total extracts up to 51% (w/w) from lyophilized samples

13. Qualitative and quantitative determination of fatty acid profiles In order to define the fatty acid profiles of each of the obtained total extracts, GC-FID was applied (Official method AOAC 996.06) 13

14. 14 Qualitative and quantitative determination of fatty acid profiles SFAUFA Tissueω-3ω-6ω-9otherTotal UFA Viscera21.355.1227.6340.944.9678.65 Fillets22.253.4827.1842.914.1877.75 Caviar26.353.4525.6239.994.5973.65 Fatty acid composition of extracted fish oil (Soxhlet) from fish viscera in mass ratio (% w/w)

15. 15 e-mail: stefan@tmf.ukim.edu.mk