Physical evidence that the variations in the efficiency of homologous series of antioxidants in emulsions are a result of differences in their distribution

• Tipo: Artigo em Revista Científica Internacional
• Data: 2017

Autores

Costa, M (Autor) Outra; Losada Barreiro, S (Autor) Outra; Fatima Paiva Martins (Autor) FCUP; Bravo Diaz, C (Autor) Outra

Revista

Título: Journal of the Science of Food and Agriculture

Vol. 97

Páginas: 564-571

ISSN: 0022-5142

Editora: Wiley-Blackwell

Indexação

ISI Web of Knowledge - 35 Citações

Scopus - 41 Citações

Outras Informações

ID Authenticus: P-00K-HQ5

DOI: 10.1002/jsfa.7765

Abstract (EN): BACKGROUNDThe relationships between the hydrophilic-lipophilic balance (HLB) of antioxidants (AOs) and their distributions and efficiencies in emulsions are not fully understood. Recent reports indicate that, for series of homologous antioxidants of different hydrophobicity, the variation of their efficiency with the HLB of the AO increases with the alkyl chain length up to a maximum (C-3-C-8 ester) followed by a decrease (cut-off effect). RESULTSWe determined the distributions of a series of caffeic acid derivatives in intact soybean emulsions by employing a specifically designed chemical probe located in the interfacial region of the emulsion. We also determined the AO efficiencies in the very same emulsions. We demonstrate that the variation of the percentage of AO in the interfacial region of soybean oil-in-water emulsions with the AO HLB parallels that of their antioxidant efficiency. CONCLUSIONThe results provide physical evidence that the variations in the efficiency of homologous series of antioxidants in emulsions are the result of differences in their distribution. The results confirm that, with other things being equal, there is a direct relationship between the percentage of AO in the interfacial region of the emulsions and their efficiency, providing a natural explanation, based on molecular properties, of the cut-off effect. (c) 2016 Society of Chemical Industry

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 8