Inhibition of oxidation in 10% oil‐in‐water emulsions by β‐carotene with α‐ and γ‐tocopherols

Abstract

The effects of low concentrations of β-carotene, α-, and γ-tocopherol were evaluated on autoxidation of 10% oil-in-water emulsions of rapeseed oil triacylglycerols. At concentrations of 0.45, 2, and 20 µg/g, β-carotene was a prooxidant, based on the formation of lipid hydroperoxides, hexanal, or 2-heptenal. In this emulsion,1.5, 3, and 30 µg/g of γ-tocopherol, as well as 1.5 µg/g of α-tocopherol, acted as antioxidants and inhibited both the formation and decomposition of lipid hydroperoxides. Moreover, at a level of 1.5 µg/g, γ-tocopherol was more effective as an antioxidant than α-tocopherol. At levels of 0.5 µg/g, both α-and γ-tocopherol significantly inhibited the formation of hexanal but not the formation of lipid hydroperoxides. Oxidation was effectively retarded by combinations of 2 µg/g β-carotene and 1.5 µg/g γ-or α-tocopherol. The combination of β-carotene and α-tocopherol was significantly better in retarding oxidation than α-tocopherol alone. While γ-tocopherol was an effective antioxidant, a synergistic effect between β-carotene and γ-tocopherol could not be shown. The results indicate that there is a need to protect β-carotene from oxidative destruction by employing antioxidants, such as α-and γ-tocopherol, should β-carotene be used in fat emulsions.

Optimal tocopherol concentrations to inhibit soybean oil oxidation

“…SPVD also reduced the β-carotene and total sterols concentrations. β-Carotene has been shown to interact synergistically with tocopherols in protecting oil oxidative stability (23,24); thus, SPVD processing may also remove other minor constituents that contribute to oil stability.…”

A kinetic model for co‐oxidation of β‐carotene with oleic acid

“…Unlike the oxidation of β-Car, L· is unstable; thus, the reverse reaction of Equation 8 does not need to be included in the model. In this study, the oleic acid concentration decreased slightly throughout the experiment, suggesting that the oxidation of oleic acid remained in the initial stage of the chain reaction.…”

“…The lipid is also susceptible to oxidation; hence, the oxidation of β-Car in such a system proceeds via a complicated co-oxidation mechanism accompanying the oxidation of the lipid. Several researchers have investigated the oxidation of β-Car in solution containing lipids (4)(5)(6)(7)(8)(9)(10). Most of them have discussed the antioxidative effect of β-Car on the oxidation of the lipid (4)(5)(6)(7)(8).…”

“…Several researchers have investigated the oxidation of β-Car in solution containing lipids (4)(5)(6)(7)(8)(9)(10). Most of them have discussed the antioxidative effect of β-Car on the oxidation of the lipid (4)(5)(6)(7)(8). However, Budowski and Bondi (9) and Ramakrishnan and Francis (10) have investigated the oxidation of β-Car in an organic solution containing a lipid such as cottonseed oil or methyl linoleate.…”

Effects of antioxidants on the stability of β-Carotene in O/W emulsions stabilized by Gum Arabic

“…It is well known that antioxidants are proper inhibiters of oxidation in oil-in-water emulsions. Early in 1997, Heinonen et al paid attention to the effects of β-carotene, α-tocopherol, and γ-tocopherol on antioxidation of 10 % oil-in-water emulsions of rapeseed oil triacylglycerols (Heinonen et al 1997). Different antioxidants were investigated in margarine dispersions: L-ascorbic acid, ascorbyl palmitate and dl-α-tocopherol against the lipid oxidation (Filip et al 2009).…”