Table 1.

Chemical and quality parameters of crude oils from tuna by-products, tuna liver, seabass and gilthead seabream by-products at different stages of the refining process, and cod liver oil (control).

Oil Samples	Refining Phase	Measured Parameter
		FFA (% Oleic Acid)	PV (meq O2/kg)	p-AV	TOTOX	TBARS (μM/g)
Tuna by-product oil	Crude oil	2.94 ± 0.12 a	2.31 ± 0.73 a	25.2 ± 0.08 a	29.7 ± 0.20 a	0.94 ± 0.33 a
	Degummed	3.51 ± 0.03 b	3.93 ± 0.18 b	19.2 ± 1.25 b	27.1 ± 0.79 b	1.02 ± 0.14 a
	Neutralized	3.13 ± 0.10 b	3.46 ± 0.39 b	16.9 ± 1.23 c	23.8 ± 1.06 c	2.02 ± 0.45 b
	Bleached	2.93 ± 0.04 a	2.88 ± 0.11 ab	14.4 ± 0.90 d	20.2 ± 1.34 d	1.88 ± 0.37 b
	Deodorized	2.83 ± 0.01a	3.78 ± 0.22 b*	19.5 ± 0.94 b	27.1 ± 2.15 b	1.14 ± 0.11 a
Tuna liver oil	Crude oil	3.13 ± 0.00 a	2.68 ± 0.86 a	20.9 ± 1.34 a	26.0 ± 0.14 a	2.88 ± 0.73 a
	Degummed	2.52 ± 0.05 b	3.01 ± 0.05 ab	19.1 ± 2.47 b	25.2 ± 1.17 a	1.35 ± 0.02 b
	Neutralized	2.65 ± 0.11 c	2.89 ± 0.22 ab	17.0 ± 4.78 c	22.7 ±1.22 b	1.76 ± 0.03 b
	Bleached	2.17 ± 0.03 b	2.85 ± 0.53 ab	14.0 ± 0.65 d	19.7 ± 0.43 c	1.92 ± 0.35 b
	Deodorized	2.12 ± 0.16 b	4.25 ± 0.28 c	19.2 ± 2.22 b	27.7 ± 2.22 a	1.97 ± 0.53 b
Seabass and gilthead seabream by-product oil	Crude oil	2.41 ± 0.47 a	4.63 ± 1.07 a	18.1 ± 0.19 ab	19.3 ± 2.45 a	0.53 ± 0.05 a
	Degummed	1.66 ± 0.05 b	2.70 ± 0.18 b	15.7 ± 1.12 c	20.2 ± 0.12 a	3.46 ± 2.08 b
	Neutralized	1.43 ± 0.18 b	3.13 ± 0.31 b	12.7 ± 0.65 a	18.9 ± 0.26 a	2.24 ± 1.05 bc
	Bleached	1.40 ± 0.01 b	3.44 ± 0.25 ab	11.4 ± 0.19 b	18.4 ± 0.52 a	1.14 ± 0.10 ac
	Deodorized	1.28 ± 0.15 b	4.20 ± 0.15 ab	16.5 ± 0.39 c	24.7 ± 0.32 b	1.42 ± 0.53 ac*
Cod liver oil	Control	2.15 ± 0.08	3.85 ± 0.44	13.3 ± 1.11	21.0 ± 0.18	1.63 ± 0.07

n = 30; Different superscript letters (a–d) in the same column denote statistically significant difference (p < 0.05); * Measured parameters in deodorized oils marked with * do not differ statistically (p < 0.05) from the control sample.