Consequence of Commercial Fish Frying on Some Quality Parameters of Oil with Special Reference to Trans Fat

Figures & data

Table 1 Fatty acid profiles (Mean ± SD) of fresh commercial frying oil samples (%)

Samples	C12:0	C14:0	C16:0	C18:0	C18:1c	C18:1t	C18:2c	C18:2t	C18:3	C20:0
Fresh oil-1	0.1 ± 0.0	0.1 ± 0.0	10.2 ± 0.5	3.9 ± 0.2	23.6 ± 1.2	3.0 ± 0.1	51.6 ± 2.5	0.4 ± 0.0	6.9 ± 0.3	0.2 ± 0.0
Fresh oil-2	—	—	6.9 ± 0.3	4.7 ± 0.2	26.4 ± 1.2	2.3 ± 0.1	58.5 ± 2.6	0.2 ± 0.0	0.9 ± 0.1	0.1 ± 0.0
Fresh oil-3	—	0.1 ± 0.0	3.4 ± 0.1	2.0 ± 0.1	60.1 ± 2.5	2.9 ± 0.01	21.8 ± 1.1	0.1 ± 0.0	9.5 ± 0.1	0.1 ± 0.0
Fresh oil-4	—	0.4 ± 0.01	14.6 ± 0.7	3.2 ± 0.2	24.1 ± 1.2	2.8 ± 0.1	52.2 ± 2.5	1.0 ± 0.0	1.3 ± 0.1	0.4 ± 0.0
Fresh oil-5	—	1.3 ± 0.05	20.5 ± 0.5	3.6 ± 0.1	21.0 ± 1.0	2.7 ± 0.1	50.1 ± 2.4	—	0.8 ± 0.0	—
Fresh oil-6	0.2 ± 0.0	0.9 ± 0.04	38.9 ± 1.5	4.5 ± 0.2	30.8 ± 1.3	11.5 ± 0.5	11.7 ± 0.5	1.5 ± 0.0	—	—

Table 2 Fatty acid profiles (Mean ± SD) of null replenishment (NR) and discarded commercial frying oil samples (%)

Samples	C12:0	C14:0	C16:0	C18:0	C18:1c	C18:1t	C18:2c	C18:2t	C18:3	C20:0
Frying oil-1
NR	0.1 ± 0.0	0.2 ± 0.0	14.1 ± 0.6	4.8 ± 0.2	20.6 ± 0.8	5.9 ± 0.2	48.0 ± 2.1	0.9 ± 0.0	5.2 ± 0.2	0.2 ± 0.0
Discarded	0.1 ± 0.0	0.2 ± 0.0	20.6 ± 0.8	6.3 ± 0.3	18.4 ± 0.6	11.8 ± 0.5	38.4 ± 1.8	1.4 ± 0.1	2.1 ± 0.1	0.7 ± 0.0
Frying oil-2
NR	—	—	7.6 ± 0.3	5.4 ± 0.2	25.0 ± 0.7	5.4 ± 0.2	55.1 ± 2.1	0.3 ± 0.0	0.7 ± 0.0	0.5 ± 0.0
Discarded	—	—	10.8 ± 0.5	6.9 ± 0.3	22.1 ± 0.5	8.0 ± 0.3	48.7 ± 1.5	2.4 ± 0.1	0.4 ± 0.0	0.7 ± 0.0
Frying oil-3
NR	—	0.3 ± 0.0	5.7 ± 0.2	3.2 ± 0.2	58.2 ± 2.2	6.7 ± 0.3	17.5 ± 0.6	0.1 ± 0.0	7.8 ± 0.3	0.5 ± 0.0
Discarded	—	0.5 ± 0.0	8.2 ± 0.3	6.3 ± 0.2	54.9 ± 2.3	13.0 ± 0.5	9.5 ± 0.3	1.6 ± 0.1	5.2 ± 0.2	0.8 ± 0.0
Frying oil-4
NR	—	0.4 ± 0.0	16.3 ± 0.6	5.4 ± 0.2	21.6 ± 0.9	4.9 ± 0.2	48.3 ± 1.6	1.4 ± 0.1	1.1 ± 0.1	0.6 ± 0.0
Discarded	—	0.7 ± 0.1	19.7 ± 0.8	9.3 ± 0.4	17.6 ± 0.8	11.8 ± 0.5	36.7 ± 1.4	2.7 ± 0.2	0.6 ± 0.0	0.9 ± 0.0
Frying oil-5
NR	—	1.8 ± 0.1	26.9 ± 1.2	5.2 ± 0.2	15.4 ± 0.5	5.6 ± 0.2	44.5 ± 1.9	—	0.6 ± 0.0	—
Discarded	—	2.7 ± 0.2	32.1 ± 1.5	8.4 ± 0.4	11.1 ± 0.4	7.3 ± 0.3	38.2 ± 1.5	—	0.2 ± 0.0	—
Frying oil-6
NR	0.3 ± 0.0	1.1 ± 0.1	41.7 ± 1.9	7.5 ± 0.3	24.4 ± 1.2	13.1 ± 0.6	10.2 ± 0.4	1.7 ± 0.1	—	—
Discarded	0.8 ± 0.1	1.7 ± 0.1	44.3 ± 1.9	10.1 ± 0.5	14.7 ± 0.5	18.4 ± 0.8	7.6 ± 0.3	2.4 ± 0.1	—	—

Table 3 Main fatty acid groups (%) and their ratio of fresh, null replenishment (NR) and discarded commercial frying oil samples

Samples	Σ SFA	Σ UFA	Cis MUFA	Trans MUFA	Σ MUFA	Cis PUFA C18:2	Trans PUFA C18:2	Cis PUFA C18:3	Σ PUFA	Σ TFA	Cis PUFA/ SFA	SFA/ UFA	Trans/ cis	C18:2/ C16:0
Frying oil-1
Fresh	14.5	85.5	23.6	3.0	26.6	51.6	0.4	6.9	58.9	3.4	4.0	0.2	0.04	5.1
NR	19.4	80.6	20.6	5.9	26.5	48.0	0.9	5.2	54.1	6.8	2.7	0.2	0.09	3.4
Discarded	27.9	72.1	18.4	11.8	30.2	38.4	1.4	2.1	41.9	13.2	1.5	0.4	0.22	1.9
Frying oil-2
Fresh	11.7	88.3	26.4	2.3	28.7	58.5	0.2	0.9	59.6	2.5	5.1	0.1	0.03	8.5
NR	13.5	86.5	25.0	5.4	30.4	55.1	0.3	0.7	56.1	5.7	4.1	0.2	0.07	7.3
Discarded	18.4	81.6	22.1	8.0	30.1	48.7	2.4	0.4	51.5	10.4	2.7	0.2	0.15	4.3
Frying oil-3
Fresh	5.6	94.4	60.1	2.9	63.0	21.8	0.1	9.5	31.4	3.0	5.6	0.1	0.03	6.4
NR	9.7	90.3	58.2	6.7	64.9	17.5	0.1	7.8	25.4	6.8	2.6	0.1	0.08	3.1
Discarded	15.8	84.2	54.9	13.0	67.9	9.5	1.6	5.2	16.3	14.6	0.9	0.2	0.21	1.2
Frying oil-4
Fresh	18.6	81.4	24.1	2.8	26.9	52.2	1.0	1.3	54.5	3.8	2.9	0.2	0.05	3.6
NR	22.7	77.3	21.6	4.9	26.5	48.3	1.4	1.1	50.8	6.3	2.2	0.3	0.09	3.0
Discarded	30.6	69.4	17.6	11.8	29.4	36.7	2.7	0.6	40.0	14.5	1.2	0.4	0.26	1.9
Frying oil-5
Fresh	25.4	74.6	21.0	2.7	23.7	50.1	—	0.8	50.9	2.7	2.0	0.3	0.04	2.4
NR	33.9	66.1	15.4	5.6	21.0	44.5	—	0.6	45.1	5.6	1.3	0.5	0.09	1.7
Discarded	43.2	56.8	11.1	7.3	18.4	38.2	—	0.2	38.4	7.3	0.9	0.8	0.15	1.2
Frying oil-6
Fresh	44.5	55.5	30.8	11.5	42.3	11.7	1.5	—	13.2	13.0	0.3	0.8	0.31	0.3
NR	50.6	49.4	24.4	13.1	37.5	10.2	1.7	—	10.9	14.8	0.2	1.0	0.43	0.2
Discarded	56.9	43.1	14.7	18.4	33.1	7.6	2.4	—	10.0	20.8	0.1	1.3	0.93	0.2

Figure 1 Vertical drop line plot of linoleic to palmitic ratio of fresh, null replenishment (NR) and discarded frying oils of six fish commercial fryers (color figure available online).

Table 4 Free fatty acids and peroxide value (Mean ±SD) of fresh, null replenishment (NR) and discarded commercial frying oil samples

Samples	FFA (%)	Peroxide value (meq/kg)
Frying oil-1
Fresh	0.16 ± 0.0	2.50 ± 0.0
NR	0.73 ± 0.0	4.03 ± 0.1
Discarded	2.17 ± 0.1	7.69 ± 0.3
Frying oil-2
Fresh	0.14 ± 0.0	2.01 ± 0.1
NR	0.56 ± 0.1	3.40 ± 0.1
Discarded	2.09 ± 0.0	3.24 ± 0.3
Frying oil-3
Fresh	0.19 ± 0.0	3.11 ± 0.1
NR	0.94 ± 0.0	4.33 ± 0.3
Discarded	2.86 ± 0.1	8.94 ± 0.5
Frying oil-4
Fresh	0.13 ± 0.1	1.90 ± 0.1
NR	0.37 ± 0.0	3.01 ± 0.1
Discarded	2.01 ± 0.2	2.84 ± 0.2
Frying oil-5
Fresh	0.12 ± 0.1	1.15 ± 0.1
NR	0.22 ± 0.0	2.71 ± 0.1
Discarded	0.80 ± 0.2	6.94 ± 0.3
Frying oil-6
Fresh	0.24 ± 0.0	3.93 ± 0.1
NR	1.74 ± 0.4	7.51 ± 0.3
Discarded	3.39 ± 0.3	14.68 ± 0.4

Figure 2 TFA versus FFA of fresh, null replenishment (NR) and discarded frying oil samples (color figure available online).