Influence of solvent-free extraction of fish oil from catfish (Clarias magur) heads using a Taguchi orthogonal array design: A qualitative and quantitative approach

This study aimed to efficiently utilize catfish
heads, enhancing the oil extraction process while improving
the cost-effectiveness of fish byproduct management. The
study employed the wet rendering method, a solvent-free
approach, utilizing a two-factor Taguchi orthogonal array
design to identify critical parameters for optimizing oil yield
and ensuring high-quality oil attributes. The extraction tem-
perature (80–120°C) and time (5–25 min) were chosen as
variables in the wet rendering process. Range analysis iden-
tified the extraction time as a more significant (p < 0.05)
factor for most parameters, including oil yield, oil recovery,
acid value, free fatty acids, peroxide value, and thiobarbi-
turic acid reactive substances. The extraction temperature
was more significant (p < 0.05) for oil color. Consequently,
the wet rendering method was optimized, resulting in an
extraction temperature of 80°C and an extraction time of
25 min, yielding the highest oil yield. This optimized wet
rendering process recovered 6.37 g/100 g of oil with an
impressive 54.16% oil recovery rate, demonstrating compar-
able performance to traditional solvent extraction methods.
Moreover, Fourier transfer infrared spectra analysis revealed
distinct peaks associated with triacylglycerols and polyunsatu-
rated fatty acids (PUFA). The oil recovered under optimized
conditions contained higher levels of PUFA, including oleic acid
(189.92 μg/g of oil), linoleic acid (169.92 μg/g of oil), eicosapen-
taenoic acid (17.41 μg/g of oil), and docosahexaenoic acid
(20.82 μg/g of oil). Volatile compound analysis revealed lower
levels of secondary oxidation compounds under optimized
conditions. This optimized wet rendering method offers prac-
tical advantages in terms of cost-efficiency, sustainability,
reduced environmental impact, and enhanced oil quality,
making it an attractive option for the fish processing indus-
tries. Future research possibilities may include the purifica-
tion of the catfish head oil and its application in the food and
pharmaceutical industries.