Why is brine added to some canned vegetables?

In the context of canning, brine—a concentrated solution of salt and water—is added to containers alongside vegetables to facilitate the processing and preservation of the product.12

During the canning of vegetables like green beans, cans are filled with either hot water and dry salt or a prepared brine before being sealed and subjected to heat treatment. Beyond its role in canning, brine is widely recognized in food preservation for its ability to act as a preservative. In pickling, for example, the addition of salt suppresses undesirable microbial activity, which helps create a favorable environment for controlled fermentation.123