To root these pineapples you must first pull all the fruit off, leaving the stem and leaves. Next peel the leaves off starting at the bottom until about 1/2 to 1 inch of the stem is showing.
the next step is to let the stem callus over for a few days, or however long it takes for the stem to form a hard dry layer around the outside.
Next just stick the majority of the callused and cleared stem into water and wait. Roots should form within a week or two!
Have fun. This method works quite well.

any idea why these fruit never matured? And if these tops grow, will their fruit be under developed too? just curious

Oh, hahaha. I didn't realize that was the entire fruit. I thought you had already eaten them. Isn't that curious....

I really have no idea why they didn't grow. They might have received too much ethylene and just riped at the point where they were at. Hard to say....

From my experience and what I've read usually the size of your pineapple bush is an indication on what size fruit it will produce. Another reason is that as a pineapple bush ages, the fruit become smaller. How old and big are your pineapple plants?

You can grow new pineapples from the tops of those 2 small ones. Just follow growerman's directions. My method is similar. Since they will be new plants, they will usually produce larger fruit...... especially if they are given time and great conditions to grow large before flowering.

I'm trying the water method next. Out of at least 10 tops i've tried, 1! has taken root using my soil method. I'm sick of that method! Also... Growing out the seeds is a joke, because they never sprout!

The plants are probably only about 10 inches tall...and since I've picked off the fruit (and subsequently pulled leaves off and put into water) the mother plant is starting ot look dried out...the spiked ends are browning...I keep them inside where it's typically about 68-70 (DH likes it cool) and the soil is moist, I let it dry out between waterings...so I"m not sure what gives on these guys...

any thoughts?

rjinga are your pineapple tops getting A LOT of sun light? They need plenty of sun light. Some of the leaves will brown but pay close attention to the center of the crown... if it starts to brown terribly that isn't good. But that doesn't mean your top won't grow. Can you see the roots? If so, are they getting longer? Pineapple tops take a little while to start catching unless you plant them in the heat of late spring early summer. They like heat. Give it time and look for root and new leaf growth.

You grew dwarf (or miniature) pineapples. They are genetically small. Most of the plants sold as houseplants are the miniature kind. Although the foliage is similar in size to the regular sized pineapple (ananas cosumos), the fruit you got are at their full mature size.