My first attempts at white background stock photography

I noticed that stock photos about things often appear on a perfect white background. Now here is my very first attempt to have the perfect white background.
Photographied was a quince. Ugly, fluffy. Used my SMC Pentax-M 50mm f1.7 manual lens (75 on digital camera) because that is at least sharp. No cutout was needed, I could go as close as this
Put it down on the balcony ground on a sheet of white paper. Just plain office paper I use for printing.
This is what came out of the camera:

Two things may be noticed on the first photo:
1. balcony railings are visible
2. paper structure is visible on the shady place.


I first put some white balance and added saturation in Lightroom and then continued with the jpg export in Photoshop. I used the clone tool to make the shadoes on the railings disappear (are they visible on the quince? I do not see them, but there I did not attempt to remove the shadow).
The great thing I finally did was to "replace colour" in Photoshop (Image/Adjustments/Replace Color). Picked the greyish background which should be snow white and replaced it to become snow white. Only the desired shadows of the fruit remained. I like this replace color tool, I should experiment with that some more.

The result:


Now I am thinking about how to have better looking white surfaces in a photo like this because the shade could not be altered.
Besides, this blog post about how to make a white background picture without shadows is most useful.