Food additive manufacturing with lipid-based inks: Evaluation of phytosterol-lecithin oleogels

Abstract

Structured vegetable oils can replace animal-derived fats providing healthier products. 3D food printing is a toll for designing complex and tailored foods. Nonetheless, the printability of oleogels is yet an underexplored topic. Herein, we report on water-free sunflower oil oleogels comprising lecithin and phytosterols with room temperature printability. The printability was optimized based on four geometric features, time stability, total solids, phytosterol-lecithin ratio, speed, and number of layers. The microstructure, X-ray diffraction, texture, printing tests, and design of experiments revealed highly printable oleogels at both low (≥20%) and high solids (up to 80%), for specific ratios of phytosterol-lecithin. Those presented a needle-like microstructure with polymorphic forms β′ and β-crystals. Some texture properties (e.g., adhesiveness) were significantly affected by the speed, total solids and ratio. With this work we propose using highly printable oleogels for different food applications, nevertheless future work should clarify how printed oleogels will behave when incorporated in a food matrix.