Graphical Abstract Highlight Research Innovative Use of By-Products: The study explores the use of tuna eye by-products, a rich source of docosahexaenoic acid (DHA), to reduce reliance on imported fish oil and promote sustainable utilization of fishery waste. Enhanced Extraction Methodology: Enzymatic extraction using papain at optimal concentrations significantly improves the yield and quality of tuna eye oil, achieving up to six times higher yield compared to other methods. Nutritional and Quality Benefits: The extracted oil demonstrated low Index of Atherogenicity (IA) and Index of Thrombogenicity (IT), indicating its potential as a heart-healthy dietary supplement, with DHA and EPA concentrations well preserved. Environmental and Safety Advantages: The enzymatic process is solvent-free, minimizing environmental impact and ensuring consumer safety, while also addressing challenges posed by extended sample storage during the COVID-19 pandemic. Abstract Docosahexaenoic acid (DHA) is an essential omega-3 fatty acid, a major component of the human frontal cortex performing a significant role in the fetal brain and retinal development. Deficiency of this component, especially in fetuses, infants, and young children, triggers poor brain neurodevelopment and cognitive impairment. Compulsion of fish oil rich in DHA fulfilled by imports reaching 9,124,579 kg in 2021. In the interim, utilization of potential by-products (tuna’s eyes) as a source of DHA has not been piloted on account of some constraints, one of which is yield that has not been maximized. Enzymatic oil extraction is considered green extraction which is safer and produces higher yields than conventional extraction using high temperatures and chemical solvents. The purpose of this study was to determine the optimal concentration of papain in enzymatic extraction to obtain the highest possible yield of tuna eye oil and the quality of extracted tuna eye oil. The best results were obtained from the extraction with papain enzyme 1% at 55°C for 1 hour, giving an optimal yield. The best yield produced was 8.59 ± 0.69%, or six times higher than cold extraction (centrifugation) without enzyme addition (1.41 ± 0.07%). Adding enzyme concentration up to 1% resulted in increased yield, decreased dark color, decreased viscosity, and improved oxidation quality. The study found that the Index of Atherogenicity (IA) and Index of Thrombogenicity (IT) values fell within low ranges 0.38-0.40 and 0.20-0.21, respectively. Heating during the enzymatic hydrolysis process (55°C) for 1 hour did not significantly alter the percentage of PUFA, and especially DHA remained well preserved.
Read full abstract