Abstract

This research studied the optimization conditions for separation and purification of omega-3 (ω-3) fatty acids from the by-product of tuna canning processing by urea crystallization. Crystallization reaction conditions of urea inclusion (urea to fatty acid ratio (X₁) and crystallization time (X₂)) were optimized using the Response Surface Methodology (RSM) and a model was developed. Optimization results showed a quadratic polynomial regression equation of Y = 24.44X₁ + 5.65X₂ - 8.71X₁²- 0.19X₂² + 1.171X₁X₂ -12.95. The maximum response was obtained at an urea to fatty acid ratio of 2.99:1 and a crystallization time of 23.64 h and predicted response of 90.44%. Analysis of variance showed that the urea to fatty acid ratio and crystallization time affected the response. Verification under optimal conditions showed that the purity of ω-3 fatty acids was 89.64% and the enrichment was 2.85 fold. Verification result revealed that the predicted value from this model was reasonably close to the experimentally observed value. The urea crystallization process changed oil quality parameters including oxidation level (peroxide, anisidin, and totox values), Fe, Cu and P concentrations and moisture content and this were mostly due to the saponification process before urea crystallization.

Keywords:

By product, concentrate, omega-3 fatty acid, RSM, tuna oil, urea crystallization,

References

Competing interests

The authors have no competing interests.

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The authors have no competing interests.