Effect of transesterification of lard on stability, antioxidant‐synergist efficiency, and rancidity development

Abstract

Glyceride rearrangement of lard did not affect its resistance to oxidation or alter the efficiency of antioxidants and synergists. Changes in stability were due to the decomposition of toeopherol and the formation of reducing substances. The position of unsaturated fatty acids in the glyeeride may influence the free v(flatile carbonyl compounds present in autoxidized lard and in rancidity development. Interesterifieation under vacuum produced an odorless and colorless randomized lard with natural stability in the range of the parent lard.

Effect of Linoleic Acid Position in Triacylglycerols on their Oxidative Stability

“…Raghuveer and Hammond (4) and Wada and Koizumi (5) found that increased unsaturated FA on carbon 2 increased TAG stability. Conversely, Zalewski and Gaddis (6) found that increase in unsaturated FA on carbon 2 decreased TAG oxidative stability. Other workers, e.g.…”

Effect of Positional Distribution of Linoleic Acid on Oxidative Stability of Triacylglycerol Molecules Determined by 1H NMR

“…Furthermore, TAG shows higher resistance to oxidation when docosahexaenoic acid exists at the sn-2 position than that at the sn-1(3) position [4]. In contrast, some reports indicated that TAG containing high amounts of UFA at the sn-2 position was susceptible to oxidation [5,6]. It was also reported that the positional distribution of UFA showed no effect on the oxidation of TAG [7].…”

Influence of the position of unsaturated fatty acid esterified glycerol on the oxidation rate of triglyceride

“…From this, it might be expected that the stability of the triglyceride could be improved by shifting unsaturated fatty acids from the 1,3positions to the 2-position of glycerol. However, Zalewski and Gaddis (2) demonstrated that the oxidation of lard which was rich in triglycerides having unsaturated fatty acids linked at the 1,3-positions became faster after random interesterification. It is not certain whether the observations obtained with lard deny the abovementioned suggestion of Raghuveer and Jlammond, since the shift of unsaturated fatty acid from the 1,3-positions to the 2-position of glycerol in lard triglycerides with random interesterification was not confirmed experimentally.…”