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Fermentation Temperatures


Thomas Crawford • Tallahassee, Florida asks,

I was pouring a homebrewed Belgian wit today and I was wondering if I was about to enjoy the fruit of my labor at the proper temperature. I measured the temperature with a recently calibrated thermometer at approximately 50 ºF (10 °C). Typically, I keep my converted chest freezer at approximately 38 ºF (3.3 °C) using a refrigerator thermostat and I monitor the temperature with an accurate commercial grade thermometer. I ferment in another converted chest freezer using the same method of temperature control. The 12 ºF (6.7 °C) difference in temperature raises several questions. Are there variations between fermenting wort/beer temperature vs. ambient temperature? What, if any, affects will these temperature variations have on my finished product? Are the recommended temperatures by yeast labs suggested for wort/beer temperature or ambient temperature? Please enlighten me.

I want to clarify my understanding of your question. Your question is about fermentation temperature and this question came to you when you were pouring your wit. I will address this question,
Response by Ashton Lewis.