While eating a pear this morning, I found myself wondering why they have a characteristically gritty texture within the soft, juicy flesh. I did some quick research, and learned this:
Pears have a characteristically gritty texture caused by cells in the flesh called stone cells. Although more and more of these have been bred out, all varieties still contain them. #
It turns out these “stone cells” are examples of a sclereid, which are sclerenchyma cells that die at maturity once they form their lignin-reinforced cell walls. In fact, the volume of these cells are comprised of mostly the cell wall itself. Lignin is a tough material that plants use to reinforce their cell walls and is what makes the stone cells seem like small grits in your mouth.