What is the purpose of the "grit" in pears

I was browsing through the produce section in the supermarket and had the sudden urge to buy some fresh pears to munch on. After waiting for them to soften from their rock hard, fresh from the store state, I was sinking my teeth into the sweet, juicy goodness, and quickly thought up my first question: What is this gritty stuff crunching between my molars? A quick search of the web turned up the answer to that. Sclerosomes or scleroids, aka “stone cells.”

The flesh of some varieties tends to contain scleroids, or stone cells. Scleroids are groups of cells whose walls are thickened with lignin, which gives some pears their gritty texture.

Which leads to my new question: Why would a fruit that doesn’t form a stone/pit, be cluttered up with “stone cells?” I see that they also form the casings for seeds, but a pear has those already in it’s core.

Any botanists want to take a crack at this one? How could this be a useful adaptation?

Apparently sclerids are formed from sclerenchyma tissue whose primary function is to provide strength and support:

From here.

Many thanks Q.E.D. :slight_smile:

Tatsu