Oil from skipjack tuna eyeballs is produced by wet rendering method under mild conditions (70–90 °C for 30–60 min). Suitable condition (70 °C for 30 min) provides the oil having yield of 13.95% and acceptable color (L* = 92.26, a* = −2.17, and b* = 22.37) along with less hydrolytic and oxidative deteriorations. To increase oxidative stability, lecithin (200 and 400 ppm), α‐tocopherol (200 and 400 ppm), and their combination (1:1 ratio) at the same concentrations are added in the oil and stored for 30 d at 30 °C. Oil added with α‐tocopherol at 400 ppm shows the highest stability within the first 2 d (peroxide value = 339.28 mEq peroxide kg−1, anisidine value = 34.15, thiobarbituric acid reactive substances = 0.74 mg of MDA kg−1 of oil). However, at day 30, oil incorporated with α‐tocopherol at 400 ppm shows no differences in n‐3 fatty acids, particularly eicosapentaenoic acid and docosahexaenoic acid from the control. Also, no significant differences in FTIR spectral intensity between both samples at day 30 at wavenumbers 3013 and 1743 cm−1, representing cis‐double bond and carbonyl group, respectively, are observed. Therefore, other appropriate techniques, e.g., packaging or additives are still required for enhancement of oxidative stability of oil from skipjack tuna eyeball.
Practical Applications: Wet rendering method is an environmental friendly method for tuna oil production. However, high temperature of extraction can generate darker color and induce lipid oxidation. To increase the qualities of rendered oil, milder temperature and shorter time for oil extraction should be applied. Moreover, the use of high potential antioxidant in combination with other techniques such as packaging, etc., should be implemented for extending the shelf‐life of oil having high susceptibility toward oxidation.