Why Dough Temperature Matters
The three most important variables in dough are time, temperature and hydration. These are also variables that any baker can control with little effort. Although mostly a product of time and temperature, fermentation also relies on free water for efficiency. This means that warmer, wetter dough ferments faster, and cooler, stiffer dough ferments more slowly.
Experienced bakers can easily make adjustments on the fly to account for variables based on sight, touch, smell, taste, or just knowing what the dough is telling you. Yes, when you’ve baked enough loaves it literally speaks to you. But until you have that confidence and muscle memory, it can be helpful to have more concrete inputs to guide you.
How to Control Temperature
You can control temperature by fermenting your dough in a container that has some insulation, and adjusting the water temperature in your dough to arrive at the Final Dough Temperature (FDT) you desire. The formula is a rather simple one, and when I began to pay attention to dough temperature, my bread got better. But the single greatest improvement in my baking came when I not only began to account for dough temperature, but actively took steps to control it. This is not only because of the effect temperature has on fermentation rate, but also because the temperature you ferment dough at also has a major impact on the characteristics of the resulting bread.
This does mean that you’ll need at least one thermometer. I keep two handy personally, one probe and one infrared, but you can get by with just a probe. One that gives as close to instant read as possible is ideal, but you can pick up decent ones relatively cheaply these days.
- My favorite thermometer is the Thermaworks Pen; the accuracy in under a second is unparalleled
- For a less expensive option, check out this one on Amazon with 17,000 5-star reviews
The formula for DDT for hand mixed dough is as follows: (Flour Temp + Ambient (Bowl) Temp + Water Temp) / 3 = Final Dough Temperature
To make it even simpler, just multiply your Desired Dough Temperature by 3, then subtract the flour and ambient temps to get the water temp you will need to achieve it.
So, what should your DDT be?
Well it doesn’t have to be exact, but I’m generally aiming for a range between 73-78°F (23-26°C). And the more consistent you are with your dough temperature, the more confident you can be that your dough will be sufficiently fermented in a set amount of time. In fact, I would argue that time + temperature is as effective as percentage rise as a judge of when to cut bulk fermentation. You will, of course, need to make adjustments based on your own environment, but once you dial it in, the results are pretty consistent.
So if your kitchen is 70°F and you keep your flour in the pantry which is 68°F, you can easily obtain the correct water temperature for a FDT of 78°F:
78 x 3 = 234
234 - 70 - 68 = 96
So just add warm water at 96°F to build your dough, then cover it well for the duration of bulk fermentation. Then probe the dough a few times during your bulk to check that it is maintaining that temp. You may see a slight increase during fermentation, especially in larger doughs, or a decrease if your container isn’t well insulated, but you’ll have input to adjust your times as a result.
How to Consistently Maintain Temperature
Let's look at some high-tech and low-tech options for maintaining your temperature with factors like seasons and varying climates.
For your starter, my recommendation for consistent temperature control is the Brod & Taylor Sourdough Home. It has both a heating and cooling function so it can maintain a wide variety of temperatures. This means you can feed your starter less often without subjecting it to the stress of refrigeration, and you can confidently keep your starter warmer when preparing it to leaven dough, without fear of it getting too warm.
For bulk fermentation temperature control, nothing is simpler than the Brod & Taylor Folding Proofer. Like the Sourdough Home, it's a plug & play solution that performs really well, and it can be folded away after use for space saving. The temperature range of 70-195°F (21-90°C) means that you can use it not only for bulk fermentation and proofing dough, but also as a slow cooker or for making your own ricotta and yogurt. It is a tremendously versatile piece of kit.
In addition to those solutions from Brod & Taylor, there are some DIY setups that can also perform really well for temperature control. The easiest of those uses a seedling heat mat (ideally one with temperature control), a cooling rack or trivet, and a large storage container.
For my setup I purchased this Seedling Heat Mat with temperature control from Amazon, and used it with a cooling rack purchased from Aldi and an Araven Food Storage Container. Total cost for the setup was about $60, though you could probably repurpose a storage container you already own to cut the price in half. In addition to the temperature probe that came with the heat mat, I also use a ThermaPro sensor to monitor temperature in two zones.
This DIY setup is great for both starter and dough when ambient temperature is below DDT, but you can use the same theory in warmer climates to keep starter or dough cooler. For that, you will want an insulated cooler box, the same cooling rack and a few ice packs to place in the container. Having the remote temp sensor also helps here so you can dial in how many ice packs it takes to hold temperature steady for the longest amount of time. You'll also want extra ice packs to keep in the freezer so you can rotate them if needed.
What is Ideal Dough Temperature?
Despite the many variables in this complex, dynamic system, there are some rules of thumb that generally hold true:
- Sourdough yeast tends to prefer a temperature of 80-86°F (27-30°C).
- Heterofermentative lactic acid bacteria will tend to produce both lactic and acetic acid as well as co2 at cooler temperatures from 60-72°F (15-22°C) and will tend to produce lactic acid and ethanol at warmer temperatures from 86-99°F (30-37°C). Most sourdough yeast shut down at these warmer temperatures.
- Yeast tend to be more tolerant of both NaCl concentrations and lowering pH than lactic acid bacteria.
- Temperature and species will significantly impact production of volatile compounds responsible for both aroma and flavor.
Growth rate of two strains of F. sanfranciscensis and one of C. milleri. (Ganzel 1998)
So, within this context, you can target specific temperatures (or ranges of temperatures) for various phases of fermentation. I generally aim for FDT of 75-78°F (24-26°C) for shape retarded sourdough, and FDT of 72-73°F (22-23°C) for ambient fermentation doughs. I use lower amounts of pre-fermented flour for retarded and higher amounts for ambient.
Geeking Out
People have been baking bread for centuries without calculating DDT, but that, in and of itself, does not invalidate progress. I think it’s safe to say that we are currently in a period of enlightenment with regards to dough fermentation, with more becoming known and understood in the last decade or two than in previous centuries combined. Some of that is being driven by scientists and research, but a lot of it is being driven by production bakers (including cottage bakers) who have questioned things that the industry has historically taken for granted.
The question of ideal temperature in a sourdough system is infinitely complex. Optimum growth and fermentation temperatures for both yeast and lactic acid bacteria tend to be species specific, although most can tolerate a broad range of temperatures. But they also behave differently as their metabolic pathways change depending on environmental factors, of which temperature is one.
And that’s just the yeast and bacterial component. You also have to consider amylase and proteolytic enzyme activity, and dough rheology at various temperatures as well. Generally speaking, the warmer the dough, the greater the enzymatic activity. This is fine to a point, but these enzymes collectively both accelerate fermentation (which also further accelerates with increasing temperatures) and accelerate the breakdown of gluten (again also further accelerated by lowering of pH in the system).
Now consider the rheological aspects. Dough is viscoelastic, meaning it exhibits properties of both a solid and liquid. The cooler the dough, the more it behaves like a solid. The warmer the dough, the more it behaves like a liquid. This affects the development of gluten as it becomes increasingly difficult to develop at both higher hydration and warmer temperatures. Whereas, generally speaking, lower hydration doughs at lower temperatures will develop with more ease.
Then let's also consider product timing, workflow and desired characteristics in terms of both texture and flavor. They all contribute to the equation in terms of ideal dough temperature. If I’m doing a same day bake with entirely ambient fermentation, then I’m often aiming for a lower DDT than a shape retarded dough. Or if I want a milder flavor then I’m more likely to target temperatures that are more ideal for yeast than lactic acid bacteria. Of course the type of mix and percentage of pre-fermented flour also play into this as well.
Other factors like duration and type of mix along with handling also contribute to texture, flavor and even keeping qualities. Time, temperature and process are effectively additional ingredients to be manipulated along with flour selection to achieve a desired end-product.
So the reality is that the target desired dough temperature depends, but 72-78°F (22-26°C) effectively covers the ideal range. For the home baker, a bit above or below shouldn't impact the overall process too much, as long as you can keep close to target DDT during bulk fermentation.
How warm or cool you choose to ferment your dough depends on how mild or tangy you want your bread to be. It depends on the crumb texture you are trying to achieve. And it depends on the constraints of your equipment and your desired workflow. I think the most exciting part is that we still have much to learn as well, and the bread from those who are challenging convention will only improve as a result!
What say you?
Tell us your methods of regulating dough temperatures, what you're found in your experiments and even let us in on your own DIY set up! Comment below, or join our private community for even more.
