To prevent the sliced bananas from turning brown, just toss them with lemon juice. Or, dip into 1 quart of cold water mixed with 3 Tbsp. lemon juice. Pat the slices dry with paper towels before using.
Source: Mom
By Irishwitch from Aurora, CO
If I had to eat just half a banana, I would seal the sliced end with a spice jar cap. Works great!!