22+ How To Stop Evergreens From Turning Brown. Sometimes evergreen foliage and branches might turn brown, an unattractive. Maybe it's losing its luster and even turning brown.
A better method for preventing avocados from going brown is to blanch the fruit whole before cutting it.
Like guacamole, fresh pesto turns brown quickly. The resulting new compound is brown in color. There are scores and scores of scholarly articles out there that have examined this in depth—after all, there's a pretty big financial incentive for the produce industry to find. This trick keeps it green for over a week in the refrigerator and indefinitely in the freezer.