Why is apple-juice brown? The flesh of an apple is white, and the juice that comes immediately from it is also clear in color. Exposed to the air however, the flesh begins to take on a brownish hue (from oxidation). When the juice is extracted from the apples, is is similarly vulnerable to this oxidation and browning?
Furthermore, most apple-sauce sold in stores is not brown, thought it has doubtless been exposed to sufficient air to cause this. On the label on the back, one of the ingredients listed is Ascorbic Acid (vitamin C) “to protect color”. Presumably, the presence of Ascorbic acid (or any acid?) interferes with the browning process (can it reverse it as well?).
So, here is the crux of my question: Would the usage of Ascorbic acid in Apple-juice preparation allow you to produce an apple-juice that is clear, or at least very pale? (And would anybody want it?)
Ascorbic acid is an antioxidant, although I don’t know if it operates on the same principle with sliced apples as well as juice. However, it is common to preserve sliced apples in a fruit salad by sprinkling the salad with citrus juice.
Apple juice remains vulnerable to browning until you inactivate the enzyme that causes it. That can be done by lowering the pH, chelating the metal required for activity, or cooking the juice.
Apple sauce is usually made from cooked apples, rather than mashed then cooked, so browning isn’t much of a problem there. Ascorbic acid is often added to things to control redox potential and nonenzymatic browning.
Over here, we have “normal” apple-juice, which is yellow, and “natural” apple-juice, which is brown, because it still has some semi-solid stuff in there, which has been filtered from the normal juice.