70° F80° F (21° C27°C)
95° F (35° C) Temperature for liquids used to dissolve compressed yeasts. 80° F90° F (27° C32° C) Optimum temperature range for yeast to grow and reproduce at dough fermentation stage. 70° F80° F (21° C27°C) Recommended water temperature for bread machines. 40° F (4° C) Recommended refrigerator temperature. Used directly from the fridge, yeast is too cold to work properly. 130° F140° F (55° C60° C) Yeast cells die (thermal death point). 120° F130° F (49° C55° C) Water temperature for activating yeast designed to be mixed with the dry ingredients in a recipe. 105° F115° F (41° C46° C) Temperature of water for dry yeast reconstituted with water and sugar. The same is true for fermentation. The higher your fermentation temperature the faster your yeast will convert sugars into alcohol and carbon dioxide. While this sounds great on the surface you never really want to rush anything when it comes to making wine. Ideal Wine Fermentation Temperature Ranges. According to yeast producer Wyeast red wines should be fermented between 70 and 85 degrees F (20-30 degrees C) . You’ll get better color and tannin extraction at the higher end of this spectrum. Temperature is a vital part of fermentation in winemaking. Fermentation occurs when yeast convert sugar to alcohol and carbon dioxide (Figure 1). Due to the exothermic nature of fermentation, temperature increases as sugars are metabolized. Heat production can be managed with the usage of external temperature control. Therefore, higher ferment temperatures increase yeast activity, and vice-versa. Published literature indicates that within the range of temperatures in which yeast is operative, every one degree rise in temperature increases the rate of yeast fermentation by 3-5%. Likewise, a decrease of 1 F will cause a similar decrease in the rate of fermentation. The temperature range for optimum yeast fermentation is between 75 F-85 F. The process of fermentation also generates heat, and its measure is often used by bakeries as an effective way to monitor the degre As a general observation, the fermentation rate increases with a rise in temperature up to a maximum of perhaps 100 to 105 F (38 to 41 C). The rates of carbon dioxide generation of dough without added sugar over a 3-hr period at various temperatures within the range of 81.5 to 95 F (28 to 35 C) are shown in Graph 1. There is a specific relationship between yeast and temperatures. Like most living organisms, the metabolic activity of yeast ceases above and below certain fairly well defined temperatures. Its ability to leaven is also effected over a broad thermal range. These are summarized in Table 4 below. Once the dough or ferment temperature exceeds about 105 F (41 C), the fermentation rate declines. Yeast enzymes are generally inhibited at this temperature. Table 5 below (derived from Pyler) correlates the effects gas production and temperature in liquid ferments. As can be seen, gas production increases as the temperature rises to 100 F (38 C). There is a specific relationship between yeast and temperatures. Like most living organisms, the metabolic activity of yeast ceases above and below certain fairly well defined temperatures. Its ability to leaven is also effected over a broad thermal range. These are summarized in Table 4 below. It depends on what you mean by ideal.   The higher the temperature the faster fermentation, but yeast mortality also increases as the temperature … rises. Above a certain temperature and the yeast will be killed. Around 25 decrees C is good temperature for fast fermentation without temperature related mortality. Likewise, if the yeast cells are exposed to low temperatures, then the yeast cells would be inhibited, and so they would also not work. However, this can be fixed unlike the prior case. When temperatures become optimum again, the yeast would ferment as usual again. Yeast fermentation is affected by temperature as a result of the various different standards of temperatures that the yeasts are exposed to. If the yeasts are exposed to their optimum temperature(approximately 66.667 degrees celcuis), then this would yield the most amount of fermentation. Likewise, if the yeast cells are exposed to low temperatures, then the yeast cells would be inhibited, and so they would also not work. However, this can be fixed unlike the prior case. When temperatures become optimum again, the yeast would ferment as usual again. Because yeast generates heat during fermentation, the liquid temperature will be higher than the air temperature. The difference between the two will increase as the volume you are fermenting increases. High temperatures will kill yeast. Providing you keep the liquid temperature below 30°C all the way through fermentation (24°C for very high alcohol), you will not kill the yeast. This is easy with volumes up to 25 liters because the difference between air and liquid temperatures is only a few degrees.
https://www.exploratorium.edu/cooking/bread/yeast_temp.html http://winemakersacademy.com/effects-fermentation-temperature-wine/ http://extension.psu.edu/food/enology/wine-production/an-introduction-on-low-temperature-fermentation-in-wine-production http://www.dakotayeast.com/help-fermentation.html http://www.theartisan.net/dough_fermentation_and_temperature.htm http://www.theartisan.net/dough_fermentation_and_temperature.htm http://www.answers.com/Q/How_does_temperature_effect_yeast_fermentation http://www.answers.com/Q/How_does_temperature_effect_yeast_fermentation http://turbo-yeast.com/all-about-temperature/
temperature for yeast fermentation