The verb "fermenting" - which means undergoing the process of fermentation - is something that substances do naturally themselves. In wine-making, certain additives may speed up the process, but the maker has to wait for the ingredients to ferment themselves. So, literally "fermenting wine" refers to wine that is currently undergoing fermentation.
In your quotation, it refers to fermenting wine which has been bottled. Normally you would not bottle wine until that process had completed and the wine was ready; however, in some European winemaking regions they do bottle young, partially-fermented wine and it is sold for consumption. For example, in France, it is known as Beaujolais nouveau. When sold, it doesn't have a cork in the bottle because it would pop out; they just put a foil lid on and pierce holes in it so the wine can fizz. I've seen what a mess it can make on a supermarket floor! Perhaps it is this kind of wine that is being referred, as it could burst the bottles if they were sealed.
However, looking at the wider context of your quotation, it appears this is a metaphor and not to be taken literally.
A strikingly similar parable is found in the Bible in two of the gospel accounts, in which Jesus said that new wine should not be put into old wineskins because they would burst. In context, this illustration evidently refers to the fact that Jesus intended Christian teachings to completely replace the Jewish system of worship. Jesus preached almost exclusively to Jewish people during his lifetime (Christianity was only spread to other nationalities by his apostles after his death) and he was in effect saying that his new teaching would not just be an addition to Jewish law, but it would completely replace it.
As your quotation comes from The History of Spiritualism it would appear the writer is using this parable as a metaphor to say that new ideas were being introduced to this group of worshippers, and members were objecting to it because these new ideas were like new wine in old wineskins - their old frame of reference and beliefs could not contain the changes. Note that, in the Bible, it is not used as a metaphor.