This thread interest me because I'm presently making a 6 gallon batch of pear wine with what appears to be a slow starting fermentation. I use pear juice extracted from a steam-juicer, so the question of SO2 is discounted. (All equipment is thoroughly rinsed after sanitation) And all of my juices are pasteurized during the canning process to preserve it for later on.
My starting S.G. was 1.106. The yeast is one packet of EC 1118. Among other ingredients, there is 6 tsp. of yeast nutrient in addition to about 24 cups of sugar.
The fermentation was very slow to start. Tomorrow it will have been in the primary for a week. But the fermentation gradually started working. This morning the batch has what appears to be about a half inch head of foam on the surface and the audible "snap, crackle, and pop" of fermentation is present. I expect the usual vigorous fermentation to be present in a couple of days. The top of the primary is covered with a thin dish towel only.
I've noticed other country wines tend to display the same sort of slow starting fermentation. Don't know why but maybe I'm trying to compare this part of the process to the kit wines I've made.
For what ever reason, the slow starting fermentation seems to be the norm with my country wines. So far they have all turned out excellent. I have two bottles of pear, from this same recipe, waiting for April and the Peoples Choice tasting at Winestock.
I'd give the pear wine a little longer to start fermentation. You may be pleasantly surprised with the results.
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