Watercore
Watercore is a trait that has been bred out of commercial apple varieties because it reduces the ability to chill store apples for 6+ months and aesthetically is not pleasing to Western eyes.
It's from an accumulation of sorbitol inside and between the cells, sorbitol is the sugar alcohol that makes pears taste sweet, (and perry from pears too, as it’s not metabolised by yeasts). Watercore seems to be yet another trait that has been sacrificed at the altar of Western tastes. However other cultures favour these differences and celebrate them. Watercore is sought after in Japan due to the sweetness it brings.
Normally, a tree transports sorbitol from the leaves to the apple, in which the fruit cells then convert it into fructose. With watercore, sorbitol is translocated to the fruit faster than it can be processed. Because the cells cannot absorb the excess sorbitol, it leaks into the intracellular spaces by the osmotic pressure gradient across the cell wall. This fluid-filled space reduces light scattering, making the flesh look glassy, translucent, or water-soaked.
Environmental factors like high daytime sun/heat combined with low nighttime temperatures, as well as over-maturity and calcium deficiency, accelerate sorbitol production. Sorbitol is the primary product of photosynthesis in apples and makes up the vast majority (about 60–80%) of the carbohydrates exported from the leaves to the fruit. #apples #watercore #sorbitol
