Duff
The apples you are talking about is usually from fermenting at too high a temp.
With Dry Yeasts - go for the 34/70 for lagers or S189 is better, and the windsor/nottingham ale for ales.
Lagers ferment around 12 degrees, ales around 18 - 20.
To help stabilise teh fermenter temp i usually put the fermenter in th elaundry trough half full with water.
Then i cycle in 2-3 1.25 ltr pet bottles from the freezer to keep the temp around the 10 degree mark for lagers.
This water in the trough increases the thermal mass and severly limits the temp fluctuations. Means taht the yest works in a much more stable/narrow temp band.
Hope this helps