Effect of proanthocyanidin‐rich extracts from Chinese quince (Chaenomeles sinensis) fruit on the physical and oxidative stability of sunflower oil‐in‐water emulsions

Abstract

SummaryTo evaluate the effect of Chinese quince proanthocyanidins (PAs) on the physical and oxidative stability of sunflower oil‐in‐water (O/W) emulsions during storage, three proanthocyanidin (PA)‐rich extracts, namely water extract (WE), ethanol extract (EE), and acetone extract (AE), were prepared. When added to O/W emulsions, all the three extracts inhibited the increase in droplet size and the absolute zeta‐potential value during storage (55 °C, 24 days). All three extracts also exhibited superior antioxidative activity in the O/W emulsions. WE showed the highest efficacy in retarding lipid oxidation as proved by its lower conjugated dienes (8.18 ± 0.49 mmol L−1) and thiobarbituric substances values (0.68 ± 0.0025 mg MDA L−1), and such efficacy was similar to that of BHA at the same level. Lower molecular weight and degree of polymerisation have a positive effect on antioxidant activity of PA‐rich extracts. According to these results, all three PA‐rich extracts are potential natural antioxidants for improving the stability of food‐grade emulsions.