What is the primary use of sodium benzoate in soft drinks?

Sodium benzoate is primarily used in soft drinks for its ability to inhibit mold growth. As a preservative, it is effective in acidic environments such as those found in many soft drinks. Its antifungal properties help extend the shelf life of these beverages by preventing mold and yeast proliferation, which can spoil the product or create off-flavors.

While sodium benzoate can have some influence on the stability of flavors and colors to a degree, its primary function in this context is to protect against microbial growth, ensuring the safety and quality of the drink over time. Other preservatives might be more effective for preventing rancidity or flavor breakdown, and specific agents are typically utilized for color preservation. Hence, the primary use of sodium benzoate stands out clearly as the inhibition of mold growth.