Avocados make wonderful additions to salads and sandwiches. But sometimes you only need half an avocado for a recipe, and the remaining half can begin to discolour and turn an unappetising shade of brown quickly.
There are lots of popular approaches to preserving the bright green colour of avocados, but which ones really work?
Olive oil
Cooks reveal that you can brush the avocado’s flesh with olive oil that doesn’t have a strong taste. They say the oil keeps air from touching the part of the fruit that’s been exposed, preventing that oxidation and all the ugly brown streaks, and that you should store it in an airtight container in your fridge until you want the rest.
Cold water
According to experts, cold water helps keep an avocado from turning brown. Many chefs and cooks use this method because they need to prepare avocados in advance of restaurant service. Whether you dice, slice or just spoon out your avocado halves, you will want to immediately immerse them in ice-cold water. Apparently, the cold water keeps the avocado away from oxygen. Also, rinsing the avocado under cold water helps delay browning. This method works because it keeps out all oxygen.
Onion
Place the avocado in an air-tight container with a few large chunks of sliced onion, and cover with a lid. Conventional wisdom has it that the gases from the onion (the same ones that make your eyes burn) help to prevent oxidation of the fruit. So, by making sure that the onion comes into contact with only the skin of the avocado and not the green fruit, you should notice no difference in flavour.
Lemon juice
Many people believe that rubbing the cut surface of avocado with fresh lemon juice prevents browning because the citric acid is thought to slow oxidation. But the avocado half we brushed with lemon juice turned a disgusting dark brown, making it unfit to serve to anyone.