What ingredient can be added to fruit to prevent it from becoming mushy during cooking?

Adding salt to fruit during cooking can actually help maintain its texture and prevent it from becoming mushy. Salt functions by drawing out moisture from the fruit, which can help create a firmer consistency when cooking. This process, known as osmosis, reduces the water content in the fruit, allowing it to hold its shape better when subjected to heat.

In contrast, sugar tends to draw moisture into the fruit, which can contribute to a softer texture. Syrup, typically containing sugar and water, would further exacerbate this by adding moisture, while butter, although it can introduce flavor and richness, does not offer any structural benefit that would help in maintaining the firmness of the fruit. Therefore, using salt is a more effective strategy to ensure that the fruit remains intact and has a desirable texture after cooking.