Triacylglycerols (TAGs) exhibit a monotropic polymorphism, forming three main polymorphic forms upon crystallization: α, β’ and β. The distinct physicochemical properties of these polymorphs, such as melting temperature, subcell lattice structure, mass density, etc., significantly impact the appearance, texture, and long-term stability of a wide range products in the food and cosmetics industries. Additionally, TAGs are also of special interest in the field of controlled drug delivery and sustained release in pharmaceuticals, being a key material in the preparation of solid lipid nanoparticles. The present article outlines our current understanding of TAG phase behavior in both bulk and emulsified systems. While our primary focus are investigations involving monoacid TAGs and their mixtures, we also include illustrative examples with natural TAG oils, highlighting the knowledge transfer from simple to intricate systems. Special attention is given to recent discoveries via X-ray scattering techniques. The main factors influencing TAG polymorphism are discussed, revealing that a higher occurrence of structural defects in the TAG structure always accelerates the rate of the α → β polymorphic transformation. Diverse approaches can be employed based on the specific system: incorporating foreign molecules or solid particles into bulk TAGs, reducing drop size in dispersed systems, or using surfactants that remain fluid during TAG particle crystallization, ensuring the necessary molecular mobility for the polymorphic transformation. Furthermore, we showcase the role of TAG polymorphism on a recently discovered phenomenon: the creation of nanoparticles as small as 20 nm from initial coarse emulsions without any mechanical energy input. This analysis underscores how the broader understanding of the TAG polymorphism can be effectively applied to comprehend and control previously unexplored processes of notable practical importance.

三酰甘油 (TAG) 表现出单向多晶型现象，在结晶时形成三种主要多晶型：α、β' 和 β。这些多晶型物独特的物理化学性质，如熔化温度、亚细胞晶格结构、质量密度等，对食品和化妆品行业各种产品的外观、质地和长期稳定性产生显着影响。此外，TAG在药物的控释和缓释领域也受到特别关注，是制备固体脂质纳米颗粒的关键材料。本文概述了我们目前对散装和乳化体系中 TAG 相行为的理解。虽然我们的主要重点是涉及单酸 TAG 及其混合物的研究，但我们还提供了天然 TAG 油的说明性示例，强调了从简单系统到复杂系统的知识转移。特别关注通过X 射线散射技术的最新发现。讨论了影响TAG多态性的主要因素，发现TAG结构中结构缺陷的发生率越高，α→β多态性转化的速度就越快。根据特定的系统可以采用不同的方法：将外来分子或固体颗粒掺入块状TAG中，减小分散系统中的液滴尺寸，或使用在TAG颗粒结晶过程中保持液态的表面活性剂，确保多晶型转化所需的分子流动性。此外，我们展示了 TAG 多态性在最近发现的现象中的作用：在没有任何机械能输入的情况下，从初始粗乳液中产生小至 20 nm 的纳米颗粒。该分析强调了如何有效地应用对 TAG 多态性的更广泛理解来理解和控制具有显着实际重要性的先前未探索的过程。