racking slows down fermentation because not all the lees is dead, and by racking you have left a bunch of the live yeast at the bottom of the previous container. If you are worried about it slowing than be a little sloppy with the racking and syphon up a small amount of the lees as you go.
a stalled or stuck fermentation is a situation where there is adequate sugar for the yeast to eat, the alcohol % has not reached the point where it is toxic to the yeast, but for some other reason the fermentation has stopped. Racking does not usually cause this, in fact it can some times be a solution to the problem.
If you let it ferment out dry or cold crash it and rack off the clear liquid, you can use potassium sorbate to keep the fermentation from starting back up if there are residual sugars in the mix or if you intend to back sweeten. This will not kill the yeast but inhibit their ability to reproduce that is why the quantity of yeast in the mix must be reduced first buy cold crashing or letting it ferment out.
I personally however do not like chemicals so for me a better option IMHO is to either vat pasteurize if you want to bottle it still or bottle pasteurize if you want to bottle it carbonated.
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