Calcium hydroxide, commonly known as slaked lime, is a versatile compound widely used in various industries, including food production and construction. As a food-grade additive, it serves purposes like pH adjustment, firming agent, and nutrient fortification in items such as pickles, tortillas, and drinking water. However, its role extends significantly into construction engineering, where it plays a critical part in enhancing the durability and stability of building projects. In construction, calcium hydroxide is employed in soil stabilization, mortar, plaster, and as a key component in the production of cement and concrete. Its chemical properties help improve workability, reduce shrinkage, and increase resistance to environmental factors, making it indispensable in modern construction practices. This article explores the dual applications of food-grade calcium hydroxide and its importance in construction engineering, highlighting how this additive contributes to both safe food processing and robust infrastructure development.