My last batch of session ale was slightly over pitched with re-hydrated S-04 and spent the first 3 days around 72f. Fermentation took off like a rocket and was at my expected FG (OG1.039-FG1.009) within 72 hours. A comment by another member got me concerned about the acetaldehyde that the warm temperatures may have produced so I started digging to find out how more about this compound and how to avoid production in the future. Mostly because I dont have the ability to control temperatures outside of 68-75 ambient and assuming primary is warmer 70-78. My mistakes aside (over pitching plus warm temperatures) I found a very interesting research article from a time long ago that measured acetaldehyde during different phases in the brewing process. In short this study quantifies the increase of acetaldehyde from the bottle conditioning process which furthers what I have read and heard from other homebrewers regarding the benefits of kegging and the ability to retain a flavor; or at least in this case not contribute to additional off flavors. What was surprising was that once the compound was formed there was little if any reduction over time. http://onlinelibrary.wiley.com/doi/10.1002/j.2050-0416.1971.tb03405.x/pdf Now I will be taking this newly founded info back to the wife to explain the benefits of and reduction of carcinogens when investing in a kegging system.