The effect of monovalent (Na+, K+) and divalent (Ca2+, Mg2+) cations on rapeseed oleosome (oil body) extraction and stability at pH 7. (15th February 2020)

• Record Type: Journal Article
• Authors: Romero-Guzmán, Maria Juliana; Petris, Vasileios; De Chirico, Simone; di Bari, Vincenzo; Gray, David; Boom, Remko M.; Nikiforidis, Constantinos V.
• Is Part Of: Food chemistry. Volume 306(2020)
• Publication Date: 2020-02-15
• Subjects: Oil bodies -- Extraction -- Natural emulsion -- Rapeseed -- Oleosomes; Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2019.125578
• Languages: English
• ISSNs: 0308-8146

Abstract

Highlights: Oleosomes extraction yield at pH 7 is enhanced by the addition of cations. The highest oleosome extraction yield at pH 7 (64 wt%) was achieved with K + . Monovalent cations cause minor coalescence of oleosomes. Divalent cations cause extensive coalescence of oleosomes. Abstract: Oleosomes are storage vehicles of TAGs in plant seeds. They are protected with a phospholipid-protein monolayer and extracted with alkaline aqueous media; however, pH adjustment intensifies the extraction process. Therefore, the aim of this work was to investigate the extraction mechanism of rapeseed oleosomes at pH 7 and at the presence of monovalent and divalent cations (Na +, K +, Mg 2+, and Ca +2 ). The oleosome yield at pH 9.5 was 64 wt%, while the yield at pH 7 with H2 O was just 43 wt.%. The presence of cations at pH 7, significantly enhanced the yield, with K + giving the highest yield (64 wt.%). The cations affected the oleosome interface and their interactions. The presence of monovalent cations resulted in aggregation and minor coalescence, while divalent cations resulted in extensive coalescence. These results help to understand the interactions of oleosomes in their native matrix and design simple extraction processes at neutral conditions.