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Control your dough temperatures for consistent resultsBringing a dough or batter from the mixer at the correct temperature will save you potential makeup, proofing and baking problems later. If you spent time finding the friction factors for the different doughs and batters you mix on each of your mixers, youll find that the formula for adjusting dough temperatures is just as easy to use.
But do you know why water and/or ice can help produce 80°F doughs even on hot summer days? Lets explore that first.
How heating and cooling work
Every substance in nature tends toward equilibrium. That means everything strives to strike a balance. For example, on a hot day, a cold drink will absorb heat from the atmosphere and will warm up in an effort to equalize itself with the temperature of the atmosphere. If you leave that drink long enough, it will reach room temperature and stay there. On the other hand, on a cold day, your cup of hot chocolate will release heat into the atmosphere until it reaches equilibrium at room temperature.
So, adding cold water to warm ingredients will cool the ingredients while the water warms up, helping you to achieve the ideal dough or batter temperature. Adding warm water to cool ingredients does the reverse. In the first case, water absorbs heat; in the second case, the water releases heat.
In the United States, we measure the amount of heat absorbed or released in British thermal units, or BTUs. One BTU is the amount of energy required to heat or cool 1 lb. of water by 1°F. So, heating 1 lb. of water 10°F requires 10 BTUs. Heating 10 lbs. of water by 1°F also requires 10 BTUs.
Different substances require different amounts of BTUs to raise or lower their temperatures. For example, the same amount of BTUs required to heat 1 lb. of water by 1°F will heat up 1 lb. of aluminum by about 5°F. In fact, water requires more energy per unit of weight to raise or lower its temperature than any other substance. Thats why its a good standard to use to establish the BTU.
How ice and steam differ from water in the liquid state
Liquid water requires a tremendous amount of energy to change its physical state from a liquid to a solid (ice) or to a gas (steam). For example, to raise or lower the temperature of 1 lb. of ice by 1°F, it takes only 0.5 BTU. However, to change 1 lb. of water into ice, we have to remove 144 BTUs of energy. Conversely, to change 1 lb. of ice into water, we have to add 144 BTUs.
Remember that you can calibrate your thermometers in a dish of water and ice. The thermometer should read 32°F until all the ice has melted (or until all the water has frozen). Thats because any heat energy lost or gained between the water and the ice is used toward the 144 BTUs per lb. that it takes to melt ice or freeze water.
That heat energy has to come from someplace. When ice melts in your glass, the heat energy is being drawn from the warmer atmosphere surrounding the glass. When you use ice in your doughs, the heat energy comes from the warm ingredients in the bowl. As a result, the ice cools the ingredients, while the ingredients melt the ice.
The same thing happens when water hits the boiling point. Liquid water requires 972 BTUs per lb. to change into gaseous steam. (It takes more energy to convert water to steam than it takes to turn it into ice because water molecules tend to attract each other. To break that attraction and turn liquid water into a gas, you need more heat energy.)
As with a water-and-ice mixture, water and steam will continue to remain at 212°F until all the liquid water has become steam at 212°F. Until all the water has become steam, the gaseous steam wont rise in temperature. However, steam absorbs 972 BTUs of energy per lb. as it changes from liquid water to gaseous steam. As a result, its much more dangerous to get a steam burn than a burn from boiling water, because your skin absorbs that 972 BTUs of heat energy when the steam condenses back into liquid water.
Using water and/or ice to control the temperatures of mixtures
Unless youre mixing doughs or batters that will be refrigerated or frozen before you finish making the product, in general, youll want to have your doughs come out of the mixer at a temperature of 78° to 82°F. Most batters should come out of the mixer at about 72°F. And, if you do want to freeze a yeast-containing dough, then arriving at a finished dough temperature of between 60° and 65°F will prevent the yeast from activating too much (you dont want the yeast cells to start reproducing before they go into the freezer or youll kill them and lose their leavening power.)
The most practical way to control dough and batter temperatures is to adjust the waters temperature to the level you need to produce the desired dough or batter temperature at the end of mixing. (Keep in mind that if your formula has no water in it, you can often substitute another liquid whose temperature could be adjusted without harming or spoiling that ingredient. Or, you may need to adjust the temperatures of the ingredients themselves by keeping them in a warmer or cooler space.)
When youre mixing doughs, you usually have four factors to take into consideration: 1) room temperature; 2) flour or mix temperature; 3) mixer friction factor; and 4) water temperature. If youre using a sponge, sour, levain or other preferment, then that becomes a fifth factor to consider in arriving at the correct dough temperature. And, for batters, you have seven factors (were just counting the ingredients that usually appear in larger quantities in your formula. Please take that into consideration when looking at your own formulas, as you may need to use more or fewer factors.): 1) room temperature; 2) flour or mix temperature; 3) sugar temperature; 4) egg temperature; 5) fat or shortening temperature; 6) mixer friction factor; (LINK) and 7) water temperature.
To arrive at the desired dough temperature, you need to measure each of the factors, then find out what the water temperature should be. We all know that winter-time baking means ingredients are colder, and the room temperature itself may be cooler than in the middle of summer. So, the water temperature required is probably not going to be very cool. However, during a heat wave, when ingredient temperatures as well as the room temperature can be pretty warm, you may have to add some ice, as well as the coldest water you can provide.
How to find the right water temperature
To obtain the desired dough temperature for a straight dough, heres how youd calculate it:
Necessary water temperature = (desired dough temperature time 3) minus (room temperature + flour temperature + friction factor)
For a dough that also uses a sponge, sour, levain or other preferment, use this formula:
Necessary water temperature = (desired dough temperature time 4) minus (room temperature + preferment temperature + flour temperature + friction factor)
For a batter that has these additional ingredients, use this calculation:
Necessary water temperature = (desired dough temperature time 6) minus (room temperature + flour temperature + sugar temperature + egg temperature + fat temperature + friction factor)
Lets see how this works. To illustrate how to calculate each of these formulas, lets assume we have the following temperatures:
78°F room temperature
68°F flour temperature
90°F sponge temperature
65°F sugar temperature
78°F shortening temperature
45°F egg temperature
25 mixer friction factor
To bring a straight dough out of the mixer at a desired temperature of 80°F, wed figure the water temperature as follows:
Necessary water temperature = (80 X 3) - (78 + 68+ 25)
Necessary water temperature = 240 - 171
Necessary water temperature = 69°F
To bring a dough that uses a prefermented sponge out of the mixer at a desired temperature of 80°F, wed figure the water temperature as follows:
Necessary water temperature = (80 X 4) - (78 + 90 + 68+ 25)
Necessary water temperature = 320 - 261
Necessary water temperature = 59°F
As you can see, because weve added a warmer ingredient (the sponge at 90°F), youd need cooler water to produce a finished dough at the same 80°F temperature.
To bring a batter out of the mixer at a desired temperature of 72°F, wed figure the water temperature as follows:
Necessary water temperature = (72 X 6) - (78 + 68+ 65 + 78 + 45 + 25)
Necessary water temperature = 432 - 359
Necessary water temperature = 73°F
In the case of the batter, youve added a colder ingredient (the eggs at 45°F), so youd use warmer water to arrive at a fully mixed batter that is 72°F.
What happens when you have to use ice in your dough or batter?
Oftenand especially in the summeryour calculations will show that you need a water temperature thats below 32°F. In other words, youre going to have to use some ice.
But we cant just substitute the same weight of ice as weight of water. Remember, ice only removes 0.5 BTUs of heat energy per lb. of ice, compared to water, which removes 1 BTU per lb. of water. Also, when ice melts, changing its physical state from solid to liquid, it takes 144 BTUs of heat energy to do that. If you dont account for that amount of heat being removed from your ingredients, then youll wind up with a much colder dough or batter than you want.
Lets illustrate with a sponge dough. Suppose our desired dough temperature remains at 80°F, but the room temperature is 78°F, the flour temperature is 80°F, the sponge temperature is 88°F, and the friction factor is 50. To find the necessary water temperature, wed calculate:
Necessary water temperature = (80 X 4) - (78 + 80 + 88 + 50)
Necessary water temperature = 320 - 296
Necessary water temperature = 24°F
Fortunately, because we know that ice requires 144 BTUs of energy to melt, we can use another formula to find out just how much ice and how much water at a given temperature (for example, the temperature your water comes out of the tap) youll need to get the dough temperature you require.
Heres how to find the weight of the ice youll need (in this calculation, the number 112 is a factor that allows for the BTUs of energy the ice will absorb as it melts):
Weight of ice = weight of formula water times (available water temperature minus necessary water temperature) divided by (available water temperature plus 112)
So lets try an example. If your available water temperature from the tap is 65°F, and your formula needs 20 lbs. of water at 24°F, heres how youd calculate how much of that water needs to be ice:
Weight of ice = (20 X (65 - 24)) ÷ (65 + 112)
Weight of ice = (20 X 41) ÷ 177
Weight of ice = 820 ÷ 177
Weight of ice = 4.63 lbs. of ice, or 4 lbs. 10 oz. of ice
So, youd use 4 lbs. 10 oz. of ice and 15 lbs. 6 oz. of 65°F water (for a total of 20 lbs.) in the formula that required 20 lbs. of water at 24°F.
Obviously, when the ice melts, its going to become water, so dont forget to subtract the weight of the ice from the total weight of the water you need in your formula.
When you run into trouble, try checking temperatures first
It may look like a lot of time and trouble to figure out the exact water temperature you need or the exact amount of ice you should add. And, if youve been baking a long time, you probably already know that you need to make adjustments in the water temperature as the seasons change.
But it never hurts to doublecheck once in a while. A reliable, calibrated thermometer and a quick check of the dough or batter temperature coming out of the mixer can help you make sure that any handling or baking problems arent starting at the mixer. And if your dough or batter temperatures are off a bit, then you can use these formulas to help you get back on track.
Carol Meres Kroskey is the award-winning former senior baker editor of Bakery Production and Marketing magazine, a trade magazine that covered the entire bakery industry. Her baking experience includes stints at various retail, hotel and supermarket bakeries as baker and pastry cook. She also spent several years as an experimental baking technician for the American Institute of Baking, and as a test baker at The Long Co., a co-op for independent wholesale bakers.
You can reach her at email@example.com