Long-term stable emulsions prepared from lentil protein fibrillar aggregates

Abstract

This present study investigated lentil proteins-based aggregates as a stabilizer to form oil-in-water emulsions. Lentil proteins (LP) were heated at neutral and acidic pH to form particulate (pH 7.0) and fibrillar aggregates (pH 2.0). The impacts of aggregate type, protein aggregate concentration, and oil fractions (ϕ) on the emulsion stability were systematically investigated. The results reveal that neither lentil protein solutions nor its particulate aggregates effectively stabilized O/W emulsions, but the LP fibrillar aggregates could form long-term stable emulsions. Due to their elongated structure, fibrillar aggregates may better adsorb and arrange at the oil/water interface to form a strong solid coating to limit coalescence and creaming. The confocal microscopic image revealed that the fibrillar aggregates could be interconnected to form a network in the continuous phase to further stabilize the oil droplets. This research has demonstrated that the construction of fibrillar aggregates can provide a new strategy to form stable plant proteins-based emulsions without using synthetic surfactants. Although the LP fibrillar aggregates were prepared at acidic pH, the suspension could be adjusted to pH 5–7 for effective stabilization of the emulsions against coalescence and creaming, thus allow wide applications in both food and cosmetic formulations.