Any decrease in feed costs will show a substantial influence on the productivity and profits of the animal industry that can be achieved through maximizing feed effectiveness, specifically by enhancing nutrient metabolism assimilation. Emulsifying agents are used to change a hydrophobic surface into a hydrophilic environment. This improves energy efficiency, lowers feed costs, and supports more sustainable animal production. Emulsification is influenced by fat properties, including the length of chains, fatty acid placement on triglycerides, and fat saturation. For instance, the crucial lipid classes known as phospholipids help in gut’s lipid emulsification and enhance long-chain fatty acids absorption in the intestine, while also maintaining the structure and functionality of cellular membranes and thus improving feed intake and growth. In fish and crustaceans, feed formulations, due to fish meal, are expensive and of limited resource, and phospholipids may be useful in formulations that use less fish meal. Lecithin is particularly well known for being a reliable source of highly bioavailable phospholipids. The inclusion of emulsifiers in commercial aquafeeds along with the increased utilization of protein alternatives has contributed to reducing fish meal dependence, creating sustainable and cost-effective feeds for the fishery industry without compromising feed conversion ratio or specific growth rates. Emulsifiers can enhance performance when added to nutritionally adequate diets, as well as low-energy diets. © 2025 Elsevier Inc. All rights are reserved.