In fact, the apple with rock candy heart is also red Fuji. In fact, rock candy apple is not a variety, but a product of watching the season. At some point, the weather is colder and frosty, and the apple freezes slightly, forming a sugar heart in the middle, which is what everyone says.

You can try to buy a box of candy apples in the market and leave them at home if you can't finish them. After a while, the candy heart will melt and disappear, because the temperature at home is relatively high, which leads to the candy heart.