Influence of Oxidants on the Stability of Tocopherol in Model Nanoemulsions: Role of Interfacial Membrane Organized by Nonionic Emulsifiers

Table 1

The initial decomposition rate (mmol/kg emulsion/day) of α-tocopherol in emulsions stabilized with emulsifiers having various sizes of hydrophilic and hydrophobic groups.

	Environmental stress	Emulsifier used for emulsion preparation
		P10L	P10S	P20S	P23L	P100S
pH 7	No	^AB0.0185 ± 0.0108^ab	^B0.0034 ± 0.0007^b	^B0.0083 ± 0.0094^b	^A0.0098 ± 0.0109^ab	^A0.0266 ± 0.0095^a
	Ferrous iron	^ABC0.0142 ± 0.0003^c	^AB0.0210 ± 0.0000^b	^A0.0250 ± 0.0009^a	^A0.0242 ± 0.0028^a	^A0.0211 ± 0.0002^b
	Ferric iron	^A0.0210 ± 0.0093^a	^AB0.0231 ± 0.0028^a	^A0.0215 ± 0.0035^a	^A0.0258 ± 0.0323^a	^A0.0230 ± 0.0061^a
pH 3	No	^ABC0.0173 ± 0.0004^b	^B0.0030 ± 0.0000^c	^B0.0034 ± 0.0005^c	^A0.0030 ± 0.0005^c	^A0.0188 ± 0.0011^a
	Ferrous iron	^A0.0226 ± 0.0017^a	^AB0.0225 ± 0.0021^a	^A0.0250 ± 0.0009^a	^A0.0217 ± 0.0042^a	^A0.0107 ± 0.0011^b
	Ferric iron	^A0.0231 ± 0.0060^a	^A0.0330 ± 0.0407^a	^A0.0264 ± 0.0101^a	^A0.0364 ± 0.0467^a	^A0.0198 ± 0.0236^a

P10L, polyoxyethylene 10 lauryl ether; P10S, polyoxyethylene 10 stearyl ether; P20S, polyoxyethylene 20 stearyl ether; P23L, polyoxyethylene 23 lauryl ether; P100S, polyoxyethylene 100 stearyl ether. The values with different small letter superscripts in the same row are significantly different () by Duncan’s multiple range test. The values with different capital letter superscripts in the same column are significantly different () by Duncan’s multiple range test.