Specifically produce, however we grow most of what we eat. We pressure can, dehydrate and ferment to preserve. I have background and decades of experience in growing, which is to say it's more than just standard hobby garden level.
The RO water is not to avoid microplastics (although that might a side benefit) but rather that the water is highly mineralized. It would be a long post to explain why I do this. Some is theoretical health concerns, some is more practical.