What is the S.G.? Foaming just means that fermentation is taking place. Some yeasts seem to produce more than others. The real tool for finding out what is happening is the hydrometer.
Well, it's the third year I am doing grape wine and I know that there is some rising of pulps but this is the double of it. I have never used yeast for grape wine.
In fact, I was afraid I had done some damage with that fruit mixer.
and frankly I wodn't know what to do with a hydrometre. I guess I have to read more.