If freezing is your aim, picking out the freshest, most crisp and firm apples is essential; this will ensure that the fruit will last longer when it is frozen. Choosing apples that are too ripe and soft to the touch will result in frozen fruit devoid of its original taste and texture - in addition, the fruit can also go bad in a short space of time, if you freeze it when it is over-ripe.
After washing the apples, peel them and take out the seeds and core. Slice them lengthwise into pieces that are not too small or too big. Usually, normal sized apples are cut into twelfths, while bigger sized ones can be cut into sixteenths.
It is a well known fact that apples are easily affected by the environment around them once they are cut open, and tend to go brown quickly. This is a natural process known as oxidation, which happens in a matter of minutes. However, this can be avoided by adding ½ a teaspoon of ascorbic acid to three tablespoons of water. Make sure you mix the two together, and then sprinkle this mixture over the cut apple slices.
After the apples are ready to be frozen, place them on a tray of your choice and clear enough space in the freezer so the tray can sit inside without being disturbed by other items. The apple slices need to spaced widely apart when you put them on the tray, to ensure thorough freezing all around. Place the tray in the freezer and after an hour or so, the apple slices should be frozen.
After the apple slices have been properly frozen, take them off the tray, place them in a freezer bag, and store them anywhere in the freezer. They can be used whenever you wish, for up to a year, after which they will eventually go bad and be unfit for consumption.