Harvesting yeast issue

[sethscider]

I have recently harvested some yeast from an old Rosie.. i have been slowly building it up with bigger quantities of juice and was going to use it for a 25 liter batch this weekend.

I have just tasted the apple juice that it is fermenting now and it is very sour.. is this a sign of infection? It looks the same and smells the same as any cider i have made before.

 

[bernardsmith]

Sour ... or bitter? Do you know what the TA is? Do you know what the gravity is? The wine may be quite acidic (not sour) and if it is very dry (no residual sugar) then there is no sweetness to offset the acidity. You might pour a glass and add some sugar to see if that cuts the bitterness. A sour taste (not the same as a bitter taste) might signify infection..