Effect of Ascorbic Acid on the Oxidative Stability of Water-In-Oil Emulsion in the Presence of Lipophilic Antioxidants

Figures & data

TABLE 1 Effect of ascorbic acid on oxidative stability of emulsions at 35°C

			OXF
Antioxidant used	IP^† (h)	Pc	Day 2	Day 4	Day 6	Day 8	Day 10
Control	2.40 ± 0.06	—	—	—	—	—	—
TBHQ	3.79 ± 0.09	1.58	0.65	0.43	0.45	0.49	0.54
5 ppm ascorbic acid	2.07 ± 0.10	0.86	0.85	0.85	0.84	0.87	0.86
10 ppm ascorbic acid	2.38 ± 0.10	0.99	1.01	1.03	1.02	1.02	0.98
15 ppm ascorbic acid	2.41 ± 0.07	1.00	0.90	0.94	0.92	0.91	1.00
25 ppm ascorbic acid	2.45 ± 0.14	1.02	0.84	0.95	0.96	0.91	0.99
50 ppm ascorbic acid	2.84 ± 0.18	1.18	0.81	0.90	0.91	0.90	0.96
100 ppm ascorbic acid	3.40 ± 0.09	1.42	0.53	1.21	1.11	1.12	1.25

^†The values given are means of three consecutive experiments ± standard deviations.

FIGURE 1 Disproportionation reaction of ascorbyl radical anion.

FIGURE 2 Effect of (a) ascorbic acid and (b) ascorbic acid with KEE and curcuminoids on oxidative stability (peroxide formation) of emulsions at 35°C.

TABLE 2 Effect of ascorbic acid on antioxidant activity of KEE and curcuminoids in emulsions at 35°C

			OXF
Antioxidant used	IP^† (h)	Pc	Day 2	Day 4	Day 6	Day 8	Day 10
Control	2.40 ± 0.06	—	—	—	—	—	—
TBHQ	3.79 ± 0.09	1.58	0.65	0.43	0.45	0.49	0.54
50 ppm curcuminoids	3.64 ± 0.11	1.52	0.29	0.73	0.67	0.73	0.84
50 ppm curcuminoids + 5 ppm ascorbic acid	4.74 ± 0.18	1.98	0.73	0.72	0.79	0.84	0.83
50 ppm curcuminoids + 100 ppm ascorbic acid	4.10 ± 0.17	1.71	0.41	0.97	0.89	0.94	1.11
2% KEE	3.96 ± 0.17	1.65	0.65	0.67	0.59	0.60	0.64
2% KEE + 5 ppm ascorbic acid	4.74 ± 0.05	1.98	0.31	0.46	0.61	0.63	0.66
2% KEE + 50 ppm curcuminoids	4.07 ± 0.16	1.69	0.65	0.72	0.65	0.66	0.69
2% KEE + 50 ppm curcuminoids + 5 ppm ascorbic acid	4.88 ± 0.12	2.03	0.37	0.53	0.63	0.67	0.72
2% KEE + 50 ppm curcuminoids + 100 ppm ascorbic acid	5.26 ± 0.14	2.19	0.53	0.67	0.72	0.79	0.87

^†The values given are means of three consecutive experiments ± standard deviations.