Apple juice has changed color because of oxidation, but it is still drinkable. It turns brown after oxidation with oxygen, and there is no safety problem, but the content of vitamin C is reduced. It is inevitable that the juice squeezed at home cannot be degassed and turned black. It's best to drink fresh.

Freshly squeezed apple juice will also change color, because apples contain iron, which will oxidize with oxygen in the air and turn black. Soak in salt water for 10 minute before pressing, add a little salt in the juice after pressing to avoid blackening, or drop some lemon juice before pressing, which will not change color and keep the original flavor.

Apple juice (cider) is a cheap drink to improve health and a source of soluble and insoluble cellulose. There are cloudy apple juice and transparent apple juice. Their basic processing technology is the same, but the difference is that cloudy apple juice adopts homogenization step, while clarified apple juice adopts clarification and filtration step. Apple juice will accelerate intestinal peristalsis, and if there is abnormal peristalsis in the intestine, apple juice will produce gas in the intestine. If the intestine is stimulated by food, you can drink ordinary apple juice or mixed juice of concentrated juice and water to reduce the stimulation. We can make our own apple juice at home, but we should drink it immediately after making it.