Low-Saturated Structured Emulsions Developed Using Glycerol Monopalmitate and Gelatin

Abstract

Structured emulsions are bi-phasic systems where the dispersed and continuous phases are organized into a specific structure using emulsifiers and structuring agents. This structure can enhance the stability and functionality of emulsions, making them suitable for various food applications. In this study, low-saturated (6-10.8% saturated fatty acids, SFA) structured emulsions (water-in-oil type, at water-to-oil ratios of 50:50, 60:40, 70:30) were prepared from corn oil at different levels of glycerol monopalmitate (GMP, 3, 4, 5%) as a commercial monoacylglycerol (MAG) and gelatin (1, 3, 5%). When GMP was used alone, a higher GMP level or lower water-to-oil ratio improved the textural parameters, as confirmed by texture profile analysis. The use of gelatin with GMP further enhanced the textural properties (p < 0.05). In terms of rheological properties, as the levels of GMP or gelatin increased, or the water-to-oil ratio decreased, the elastic (G’) and loss (G’’) moduli rose. All samples exhibited solid-like behavior (G’> G’’) at least up to 40 °C. The peak melting point of samples were recorded at 46.9–76.5 °C for samples prepared using GMP alone. When gelatin was used with GMP, peak melting point of samples rose significantly (from 51.2 to 55.6–78.4 °C) depending on gelatin concentration (p < 0.05). Emulsification using GMP alone reduced oxidative stability. However, when gelatin was used with GMP, the oxidative stability of the structured emulsions was comparable to the initial oil (p < 0.05). Therefore, the combination of gelatin and GMP allows the formulation of structured emulsions with enhanced textural and oxidative properties at lower oil and SFA content.