You have read numerous posts on this site stating that many unclassified defects should be simply described, as to their color, the size and if there is depth associated with the defect. But occasionally questions surface as to whether an anomaly found is a defect or not.
Upon cutting apples you may encounter some with having a red flesh. As long as the discoloration is red or pink this is not scored as a defect. If you find gray or brown discolored streaks you are finding internal browning or internal breakdown, which is a defect. But the apples with a red flesh are common in certain varieties of red apples and is never scored as a defect. Red Rome apples seem to exhibit this trait more so than others.
The red flesh is not caused by dye or wax being applied to the apples. It is purely a condition caused by nature, as the pigment from the red skin color is leeching into the white flesh. The red color does not affect the flavor or the storage life of the apple.