|MadSci Network: Botany|
A pineapple is a multiple fruit or multiple-accessory so is derived from the fruits of many flowers. The berries fuse with the rachis or stem of the inflorescence to form the pineapple fruit. If I bought a pineapple with "hundreds of small black seed-like items in the pulp" I would return it and ask for another one or ask for a refund. Collins (1960) says eating a seedy pineapple is like eating a normal pineapple containing a thousand tiny bits of gravel. In another MadSci answer on pineapple seeds, they were described as "oval, flatish, a dark gray-brown and about half the size of a grain of rice." Rauh (1979) described pineapple seeds as "small, thick, ovate (egg-shaped) brown or blackish." I cannot tell from your description if they are definitely seeds but it sounds likely. How can you tell that they get larger with time? That doesn't seem like the behavior of a seed in a harvested fruit but more like an insect or disease. You could examine some of the suspected seeds under a microscope and see if they have characteristics of seeds. You might also try to germinate them. The first webpage under references has a discussion of germinating pineapple seeds. If you live in the United States, you could contact your state cooperative extension service and have them examine it. References Pineapple seeds Pineapple Re: Where are the seeds in a pineapple plant? The Biology & Ecology of Pineapple (Ananas comosus var. comosus) in Australia Collins, J.C. 1960. The Pineapple. New York: Interscience. Rauh, W. 1979. Bromeliads for Home, Garden and Greenhouse. Poole, Great Britain: Blandford Press.
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