Effect of droplet size on lipid oxidation rates of oil-in-water emulsions stabilized by protein |
| |
Authors: | Laurent Lethuaut François Métro Claude Genot |
| |
Affiliation: | (1) Laboratoire d'Etude des Interactions des Molécules Alimentaires, INRA, BP 71627, F-44316 Nantes cedex 3, France |
| |
Abstract: | In emulsions lipid oxidation is mainly influenced by the properties of the interface. The aim of this work was to investigate
the effects of droplet size and interfacial area on lipid oxidation in protein-stabilized emulsions. Emulsions, made of stripped
sunflower oil (30% vol/vol) and stabilized by BSA were characterized by surface area values equal to 0.7, 5.1, and 16.3 m2·cm−3 oil. The kinetics of O2 consumption and conjugated diene (CD) formation, performed on emulsions and nonemulsified controls, showed that emulsification
prompted oxidation at an early stage. On condition that oxygen concentration was not limiting, the rates of O2 consumption and CD formation were higher when the interfacial area was larger. Protein adsorbed at the interface probably
restrained this pro-oxidant effect. Once most of the O2 in the system was consumed (6–8 h), CD remained steady at a level depending directly on the ratio between oxidizable substrate
and total amount of oxygen. At this stage of aging, the amounts of primary oxidation products were similar whatever the droplet
size of the emulsion. Hexanal and pentane could be detected in the headspace of emulsions only at this stage. They were subsequently
produced at rates not depending on oil droplet size and interfacial area. |
| |
Keywords: | Conjugated dienes droplet size interfacial area lipid oxidation in emulsions oxygen protein volatile compounds |
本文献已被 SpringerLink 等数据库收录! |
|