The gritty texture of fruits such as guava, pear, and sapota is due to the presence of

Sclerenchyma is  simple permanent mechanical tissue, which is dead on maturity.It has two kinds of cells, fibres and sclereids.Sclereids are commonly present in cortex and pith of gymnosperms and dicots and also present in pulp of fruits ,seeds.Fruits like guava, sapota and pears have sclereids in pulp