Sodium lactate plays a crucial role in soap making, primarily by enhancing the hardness and longevity of the soap bars. It is a natural humectant, which means it helps the soap retain moisture, preventing it from drying out too quickly. This quality makes the soap more durable and longer-lasting. Additionally, sodium lactate aids in the soap-making process by making the mixture easier to work with, especially when pouring into molds. It helps the soap batter to set up more quickly, reducing the time needed for the soap to harden. This can be particularly beneficial for intricate designs or when using detailed molds, as it minimizes the risk of distortion. Overall, sodium lactate is a valuable ingredient that improves both the quality and usability of handmade soap.