Optimisation of Low-Toxicity Solvent Employment for Total Lipid and Tocopherol Compound Extraction from Patagonian Squid By-Products

The extraction of total lipids and tocopherol compounds from Patagonian squid (Doriteuthis gahi) by-products (viscera, heads, skin, etc.), resulting from squid mantel commercialisation, was studied. An optimisation simplex-lattice design by employing low-toxicity solvents (ethanol, acetone, and ethyl acetate) was carried out taking into account their relative concentrations. The variance analysis of data showed that the quadratic model was statistically significant (p < 0.05); empirical coded equations were obtained as a function of the low-toxicity solvent ratios. The optimised lipid extraction was obtained by employing the 0.642/0.318/0.040 (ethanol/acetone/ethyl acetate) solvent ratio, respectively, leading to an 84% recovery of the total lipids extracted by the traditional procedure. In all extracting systems tested, the presence of alpha-, gamma-, and delta-tocopherol compounds was detected, alpha-tocopherol being the most abundant. For alpha-, gamma-, and delta-tocopherol compounds, the optimisation process showed that acetone extraction led to the highest concentrations in the lipid extract obtained (2736.5, 36.8, and 2.8 mg center dot kg(-1) lipids, respectively). Taking into account the recovery yield on a by-product basis, the values obtained for the three tocopherols were included in the 88.0-97.7%, 80.0-95.0%, and 25-75% ranges, respectively, when compared to the traditional extraction. This study provides a novel and valuable possibility for alpha-tocopherol extraction from marine by-products.

Automated summary

The study focused on the extraction of total lipids and tocopherol compounds from Patagonian squid by-products using low-toxicity solvents. An optimization process determined the most effective solvent ratios. The results showed high recovery rates and concentrations of alpha-tocopherol, making this method a valuable possibility for its extraction from marine by-products.