Functional ingredients—including preservatives, antimicrobials, stabilizers, emulsifiers, thickeners, and antioxidants—are essential components in modern food formulations, providing safety, stability, and desirable sensory qualities. Preservatives and antimicrobials inhibit microbial growth, preventing spoilage and extending shelf life, while antioxidants protect against oxidative damage, maintaining flavor, color, and nutrient integrity. Stabilizers and thickeners enhance texture, viscosity, and water retention, contributing to product consistency, whereas emulsifiers enable the stable blending of immiscible ingredients such as oil and water, improving mouthfeel and appearance. Together, these functional ingredients allow manufacturers to create safe, appealing, and high-quality foods, while supporting trends toward clean-label, plant-based, and minimally processed products.