**Yes**, applying a layer of salad oil on the surface of the recorded dishes after cooling can indeed make the surface of the braised vegetables brighter and prevent the surface from drying and discoloring.

In terms of ingredients, salad oil may contain some special spices that affect the flavor of braised vegetables, but these are not used in all braised vegetables. Generally speaking, the main raw materials of stewed vegetables are meat, vegetables, spices and seasonings, etc. These ingredients themselves already have rich taste and unique flavor.

In terms of the production steps of braised vegetables, braised vegetables usually need to go through a series of processing steps, such as cleaning, cooking, soaking and seasoning. These steps can not only make the braised vegetables more delicious, but also improve the color and brightness of the braised vegetables to a certain extent. However, in order to prevent the surface of the braised vegetables from drying out and discoloring, you can apply a layer of salad oil after the braised vegetables are cooled. This can form a protective film to lock in the moisture and flavor of the braised vegetables, making them more tender and delicious.

In general, applying a layer of salad oil on the surface of the recorded dishes after cooling can not only increase the gloss of the stewed vegetables, but also prevent the surface of the stewed dishes from drying and discoloration, making the stewed dishes more delicious.