Yeast Pitching Basics

• Yeast is highly specialized based on the type of wine or beer you are making. While some yeast can tolerate temperatures above 80 degrees Fahrenheit, others will die at 50 F. Select yeast strains depending on which type of beer or wine you are making and check with the manufacturer on the appropriate temperature for that particular yeast type. Use an instant-read thermometer when brewing beer or making wine to make sure you do not kill the yeast before you even get started.

Pitching Yeast in Beer

• Beer is prepared by boiling malt and hops together to create the wort. Because the boiling is done before pitching yeast, it is extremely important you monitor the temperature precisely before inoculation. Cool the wort by submerging your kettle in an ice bath to bring its temperature down. Depending on the type of yeast you are using, the wort will need to be between 45 F and 70 F, with lager and ale beers requiring lower temperatures to prevent yeast from dying.

Pitching Yeast in Wine

• When making wine, the must, or crushed grapes, has to be below 90 F to prevent yeast from being killed. Winemakers typically aim for a must with a temperature between 70 and 80 F when pitching yeast to promote a good fermentation. The temperature must be monitored throughout fermentation to prevent it from exceeding 90 F, as this can result in a stuck fermentation, or one where the yeast dies out before all the sugar is converted to alcohol. Conversely, must temperatures need to stay above 65 F for fermentation to occur.

Adjusting Must and Wort Temperatures

• Must temperatures can be brought down using sanitized milk jugs filled with frozen water. Replace the jugs every few hours to keep the must cool and maintain an acceptable temperature throughout fermentation. To bring the temperature up, use a blanket or brew belt to raise the temperature. For wort, use a fermentation refrigerator to bring the temperature to the necessary range and maintain the temperature throughout fermentation for cooler fermentation beers. If you are making a beer that ferments at a warmer temperature, around 70 F, use a basement or other cool area of your house to maintain this temperature during fermentation.