Recovery of Polyunsaturated Fatty Acids Rich Extracts from European Carp Viscera Using Supercritical Carbon Dioxide: Artificial Neural Network Modelling

Applying green engineering principles to conventional fish processing bio-waste (viscera matrixes) suggests its reconsideration as a secondary raw material rich in highly valued polyunsaturated omega-3 and omega-6 fatty acids. Supercritical fluid carbon dioxide extraction was introduced as a separation technique with a minimal ecological footprint. The operating variables of the extraction process were set at 20, 30, 35, and 40 MPa; 313, 323, and 333 K; and 3.23, 4.62, and 5.9 g CO2/min. The artificial neural network model was designed based on the investigated output − polyunsaturated fatty acids' solubility in supercritical carbon dioxide employing the backpropagation training algorithm with the proposed 3-10-1 architecture. The model provided high accuracy (r = 0.9905), and the resulting three-dimensional space depicted the omega-3 and omega-6 solubility. The maximum yield of the total extract, 0.52 g/g freeze-dried product, was achieved at 40 MPa and 333 K.