Author Topic: Dough temperature and friction factor questions. (Read 23824 times)

jimnme · « **on:** August 05, 2005, 10:01:17 PM »

Hello,

I ran across this site a couple of weeks ago and and really intrigued. And we have a new hobby now. Tonight we decided to make sort of a practice dough using Tom Lehmann's New York recipe so we could calculate what our water temperature should be. Using a Kitchenaid stand mixer we actually have a negative 8 friction factor. Does this even sound remotely correct? Is my dough actually cooling off during kneading?

Here are some specifics. Final dough temperature was 80, flour temperature was 77, room temp was 82, and water temp was 89.

Can you tell I am a total newbie LOL. Just rather perplexed at my situation.

Thank you for any advice you may offer.

Michelle

Randy · « **Reply #1 on:** August 05, 2005, 10:29:19 PM »

Calculating final dough temperature is interesting but far from necessary for making outstanding pizza using a kitchenAid. In small batches of dough the % error in measuring temperature can quickly nullify your calculation. Measuring water temperature keeping up with knead time will do the trick.

Hope this helps.

Randy

jimnme · « **Reply #2 on:** August 05, 2005, 10:35:54 PM »

Thank you. I was a bit worried. I have been reading so much and printing it out and studying I just wanted to do everything absolutely perfectly and was really thrown off. It was only a small amount of dough so I thought that may have something to do with it.

I will have to see how it turns out tomorrow!

Thanks,
Michelle

Pete-zza · « **Reply #3 on:** August 05, 2005, 11:00:55 PM »

Michelle,

The friction factor should always be a positive number.

It sounds like you were trying to calculate the friction factor for your KitchenAid unit. The way that this is ordinarily done is to make a test batch of dough and note the temperature of the water you use to make the test batch of dough (WT), the room temperature (RT), the flour temperature (FT), and the final dough temperature (FDT). Then, the friction factor (FF) can be calculated from the following expression:

FF = (3 x FDT) - (RT + FT +WT).

Using your numbers, FF = (3 x 80) - (82 + 77 + 89) = - 8, just as you indicated. The only way I can see how you could get a minus number is if you (1) erroneously recorded one or more of the temperatures, (2) you let the dough set somewhere along the way during kneading (for example, for an autolyse or similar rest period), so that the dough in fact did cool down by the time you took its temperature, (3) you didn't take the temperature of the dough as soon as it came off the hook, but sometime later, or (4) your thermometer has a long lag time to register temperatures and you read it too soon or in an inconsistent manner (some thermometers take several seconds to respond). Also, I am a bit puzzled that the room temperature and flour temperature readings weren't much closer. The flour might have a lower temperature reading if it was brought out from a refrigerator or freezer or from a pantry that is cooler than the kitchen, but usually the flour rises close to the room temperature by the time it is measured, set aside, and used. I rarely see more than about one degree difference between flour temperature and room temperature.

You will also note that the average of the room temperature RT, flour temperature FT and water temperature WT in your example is almost 83 degrees. Without even considering the temperature effects of your KitchenAid machine, that average is higher than the finished dough temperature FDT. Absent one of the possibilities (1)-(4) noted above, that would violate the laws of physics

. You may have to go back to the drawing board. I might also add that the Lehmann dough is quite sensitive to temperature. For that reason, I always temperature adjust the water so that the finished dough temperature doesn't exceed 80-85 degrees. Other doughs seem to tolerate higher water temperatures better than the Lehmann doughs.

Peter

piroshok · « **Reply #4 on:** August 06, 2005, 07:58:16 AM »

In bread after kneading should be at 77 degrees some argue a bit more but it is not that exact anyway
I have had pretty good success using the above guide though some argue that over 80 may contribute to overfermentation

Pete-zza · « **Reply #5 on:** August 06, 2005, 08:35:54 AM »

piroshok,

Water temperature is just one consideration. For all the things you can do to accelerate the rate of dough fermentation, like using high water temperature and using a lot of yeast, the rate of fermentation can be lowered by using a lot of salt and/or a lot of sugar, both of which counteract the other two factors. Under these conditions, the dough can behave quite normally, without excessively ballooning up. In a home setting, even that isn't a big problem. But if you are making hundreds of dough balls, as is usually the case with pizza operators, small dough balls are preferred because they don't use up as much real estate in the dough boxes and coolers and are considered more stable from a dough management standpoint. Using small amounts of yeast, controlled water temperatures, and retardation (refrigeration) all serve that purpose. Even knowing all that, according to the General Mills Flour Baking group, about eighty percent of the technical calls they get from pizza operators involve issues relating to dough temperature.

Peter

jimnme · « **Reply #6 on:** August 06, 2005, 09:42:24 AM »

Thanks,

Your explanations make a lot of sense. We did not let the dough rest and took its temp as soon as it was off the hook. So we must have had an inaccurate reading. I used an instant read thermometer and I will check out the lag time. We thought this was quite curious. Now surely we did not prove physics wrong so I will try again and see what I come up with. All part of the learning process. Back to the drawing board to improve our skills.

Thanks Again.
Michelle

Added: What is the best way to measure flour temperature at home. Is a digital instant read thermometer accurate for this?

Pete-zza · « **Reply #7 on:** August 06, 2005, 10:02:33 AM »

Michelle,

The way I take the temperature of the flour is to just stick the probe of the thermometer in the flour after it has been weighed/measured out. I try not to touch the metal part of the probe so as not to affect the reading and I try to keep the probe from touching anything else. You can also just stick the probe into the flour bag and get a reading that is good enough for our purposes.

FYI, out of curiosity, this morning I checked the specs on my thermometer (an instant-read digital thermometer) and the response time is 8 seconds with 2-second updates. You might wonder what is so "instant" about that, but I have seen specs for thermometers that are even worse than that, and sometimes product reviewers will downgrade such thermometers for that reason. There will also be differences in readings between analog instant read thermometers (the ones with needles) and digital instant read thermometers. So, unless you get a really expensive digital thermometer, you aren't going to get extremely accurate measurements. But for our purposes, they will be plenty good enough.

You might also want to take note of the fact that the friction factor for your KitchenAid machine can change with the amount of dough you make and the speed at which you run your machine. For my simple KitchenAid machine and the amount of dough I make (usually around 15-20 ounces) and the speeds I use (stir and #2 mainly), I have calculated that the friction factor is around 8-10 degrees F. Even if I am off a few degrees, the dough will usually fall within the desired finished dough temperature range. At this time of year, many pizza operators switch over to using ice water to keep their doughs within the desired range. Otherwise, the dough balls can balloon up and possibly overferment and be difficult to manage.

Peter

jimnme · « **Reply #8 on:** August 06, 2005, 10:24:56 AM »

Thanks,

I have a few things to get done this morning but after that I will mess with my thermometer a bit more and try again a bit later in the day.

I had one more kind of odd question if you don't mind. We are in Florida with very high humidity right now. I know when they give our weather reports we have an actual temperature and a "feels like" temperature with the humidity factored in which can be sometimes 10 degrees or more different. Our home is air conditioned though. Does this factor in at all. When I measure my room temperature am I getting the actual temperature or the feels like. Meaning which does the thermometer read? Does it feel like us? Silly I know.

Pete-zza · « **Reply #9 on:** August 06, 2005, 11:10:19 AM »

Michelle,

Your question isn't silly. In fact, I had to scratch my head for a few moments.

Humidity affects several dough ingredients, including flour, salt, yeast and sugar. However, your instant read thermometer should be reading actual temperature. In many cases, it will be the "internal" temperature that the thermometer probe will be reading (e.g., for flour and water). Your room temperature reading will be for the ambient room temperature, whether air-conditioned or not. If heat index readings were to be used, one would have to have heat index charts in front of them, as well as the capability to measure relative humidity, before making a pizza dough.

You are correct that the heat index is often several degrees higher than actual temperature. For example, for an ambient temperature of 90 degrees F and a relative humidity reading of 50%, the heat index will be 98 degrees F (see http://www.weatherimages.org/data/heatindex.html). Using the heat index readings for dough making purposes would throw everything off.

Peter

Randy · « **Reply #10 on:** August 06, 2005, 12:17:53 PM »

Measuring flour temperature is just way beyond what you need to be concerned about. It is much more important to learn the basics first. As I pointed out earlier the original formulas Peter uses are for large batches and have minimal accuracy in Kitchen Aid size batches. Most recipes have already been tested to produce a great end product without so much detail. If you take good notes then record the dough temperature after kneading for compasions between recipes. If you don't weigh your flour and water and let flour equalize temperature with the mixer bowl then the calculation is just not going to do you any good. Weigh your flour and water and check you water temp. Keep good notes on your knead time and final dough temperature and you will be teaching us how to make pizza in no time. If you are making 25 pounds of dough then by all means run the calculation but for a one pound batch have fun with it and follow the recipe.
Start with this recipe then go from there.
http://www.pizzamaking.com/newyorkstyle.php

Pete-zza · « **Reply #11 on:** August 06, 2005, 01:44:30 PM »

Randy,

Michelle should of course go with whatever approach she is most comfortable with. For those recipes like the Lehmann dough recipe that call for a specified finished dough temperature, I routinely temperature adjust the water. It's a simple calculation and I invariably get the finished dough temperature in the specified range. To me, temperature is temperature, whether it is a single dough ball in a home setting or several as a pizza operator (several of whom are members of this forum) might make in a professional setting. It's one less thing to worry about going wrong or trying to work through when someone tells me the dough didn't come out as hoped.

When I make your American style pie, which calls for water temperature of 120 degrees F, that is what I use, even though the finished dough temperature is around 90 degrees. In the case of room-temperature fermented doughs, such as the Caputo 00 doughs, temperature adjustment means little so there is no point in doing it. Even when I use autolyse or similar rest periods for a dough that is to be refrigerated, surprisingly the dough gets close to the specified finished dough temperature range. Pftaylor routinely achieves the same results with his Raquel dough recipe. There aren't as many situations for temperature adjusting water as one might think. The Lehmann recipe is one of the few.

Again, one should experiment as much as one likes and take good notes and learn from them.

Peter

jimnme · « **Reply #12 on:** August 06, 2005, 05:00:46 PM »

Thanks to everyone. I am going to keep working at it until I have it down. There are 50 pizza places around here and none with great pizza so I'm gonna have to do it myself.

The other New York pizza recipe sounds good but I'm kind of in the same boat about the temperature. It says warm water and I'm not sure how warm it should be. I have weighed all of my ingredients. I have a gram scale I use for my birds that is quite accurate. The only real conversion I have had to do is with the yeast since I have not been able to find IDY locally, only ADY. As of yet I have never passed a windowpane test but I also read that was less important with pizza dough. I am going to have to order some IDY online to get it.

I really want to thank you all for being so patient and helpful. There aren't many places where you seasoned ones will take this much time explaining to us beginners. I appreciate it.

Michelle

Pete-zza · « **Reply #13 on:** August 06, 2005, 06:07:55 PM »

Michelle,

I'm surprised that in an area that has as many pizza places as you indicated that there isn't a supermarket that sells IDY. Fleischmann's sells a Rapid-Rise yeast that is a version of IDY (but not the same one as marketed to pizza operators or bakers), SAF sells Perfect Rise yeast that can be used like IDY, and Red Star sells a Quick-Rise IDY. Often you can tell the IDY from the ADY by the addition to the IDY of ascorbic acid (Vitamin C). The label will usually specify the ascorbic acid.

If, in fact, IDY isn't available for you to use, you can easily substitute ADY for IDY. ADY usually requires proofing in a warm liquid such as water (about 105-115 degrees F), but you only need a small amount of warm water (maybe a few tablespoons). The rest of the water is temperature controlled should you decide to go that route. If you are using volume measurements for the yeast (e.g., teaspoons or fractions thereof), you can convert from IDY to ADY in the Lehmann recipe by multiplying the volume of IDY called for in the recipe by 1.5. If you are using weight measurements (e.g., ounces or grams), you can convert from IDY to ADY in the recipe by multiplying the weight of IDY in the recipe by 1.25. If you will be using grams, you can multiply the number of ounces by 28.35 to get grams (1 oz. equals 28.35 grams).

Peter

jimnme · « **Reply #14 on:** August 06, 2005, 08:43:40 PM »

I know, it does seem odd to me. I have looked at every supermarket and we don't have any baking places around. All stores have Fleishmans ADY and bread machine yeast and Publix also has Red Star Active dry and nothing else.

This is what I have done thinking it was correct. I did this because of this part of the recipe (below). I used 1/2 as much (.25 to .375) since I used active dry. Another mistake I made was proofing it in all of the water instead of just a small amount. Then used that mix when it got to the temperature I wanted. (about 15 minutes).

I was going to try again this evening but just got too tired after running all over town to find ADY. I could go into a pizza place and ask them I guess but I doubt I could order small quantities from their supplier. I am going to order some online, I wanted to get some flour anyway and I can just add it to my order. I also bought another instant read thermometer today because I thought something just wasn't right and this one measures the flour about 3 or 4 degrees warmer than the other one. Go figure.

It looks like it may be toward the end of the week until I have time to try again. Until then I will keep reading. I see so many thing it's been hard to keep track. I have notes everywhere but need to organize them a bit.

Thanks.
Michelle

Note: If using ACTIVE DRY YEAST (ADY) only half the amo0unt as compressed yeast. Then suspend the ADY in a small quantity of warm water (105 – 110F) and allow it to stand for 10 to 15 minutes. Add this to the water in the mixing bowl, but do not add the salt and sugar to the water, instead, add the salt and sugar to the flour, then begin mixing as directed.

If using INSTANT DRY YEAST (IDY) us only 1/3 the amount as compressed yeast. Add the IDY to the flour along with the salt and sugar, and begin mixing as directed.

jimnme · « **Reply #15 on:** August 07, 2005, 12:35:49 PM »

I know I have problems. I am using a Kitchenaid Stand mixer 525 watts. I am using KA unbleached bread flour. Until I get my order in the mail that is my only choice other than AP.

I really do understand how to calculate the friction factor. My problem really was in the measurements themselves. I am testing both of my thermometers because that has to be the culprit.

Everything I make in this mixer seems to take a lot longer than everyone else. Making bread takes a heck of a long time to knead on speed 2. As far as the gluten window goes, I just don't get that part. I thought it was just taking a long time for everything to knead but I actually kneaded to let down yesterday. I have tried adding flour very slowly but I still have never seen it.

As I said I am going to try again. I will use the other recipe you posted and see how it goes.

Oh, and I never have suspended yeast in cold water. It was done in warm water. Again, until I get IDY I just need to convert the ADY.

Thanks
Michelle

Pete-zza · « **Reply #16 on:** August 07, 2005, 01:18:15 PM »

Michelle,

As you are discovering, it is not the easiest thing to teach someone how to make a pizza dough using words, especially for someone just starting. However, I keep trying. The last time I did this sort of thing was for a 12-inch Lehmann NY style dough, at Reply #190 at http://www.pizzamaking.com/forum/index.php/topic,576.180.html. I can't say that the heavens will open up after you read the post, but it might help (along with a second post linked in Reply #190). I wouldn't spend much time worrying about the window-pane test. I realize that it is a common test and is often recommended by many pizza gurus, but in due course you won't need it and you will come to rely more on the feel of the dough to know that it is ready. The most important thing for now is to just pick a good recipe and start making dough and observing the results. There's enough information on this site to fill several books on pizza, and you will be overwhelmed if you try to absorb it all before making your first pizza dough. As you gain experience, you will add to your knowledge base and pizza making skills.

Peter

Randy · « **Reply #17 on:** August 07, 2005, 01:23:24 PM »

Let's see if we can't help you a bit. IDY goes by other names and is available in almost every grocery store and every Walmart. Look for Fleischmann’s Bread Machine Yeast, it comes in a small jar.

jimnme · « **Reply #18 on:** August 07, 2005, 01:47:05 PM »

Yes!!! They do have Fleishmann's bread machine yeast! that is one of the 2 I have seen. I just didn't think that's what it was. I thought that was just for bread machines for some reason.

Ok, I just checked both of my instant read thermometers in ice water. One is 32.4 degrees which I think is close enough and the other is 33 degrees (doesn't do decimals) and it needed to be calibrated.

I am going to run an get the bread machine yeast and try again now. I am also going to take pictures along the way in case I have a problem.

Will post my results.

thanks
Michelle

Randy · « **Reply #19 on:** August 07, 2005, 02:40:25 PM »

Try this simpler recipe to get your feet on the ground. I promise you it will give you a bakers window. Then you can go Pete's recipe.

16 oz Bread flour

9.8 oz Water by weight(warm 120deg. F

1 TBS sugar

1 TBS Honey

1 Tablespoon Classico Olive Oil or vegtable oil

2 Teaspoon Salt

1 1./2 teaspoons bread machine yeast

Mix flour sugar and salt. Put yeast and half the flourmixture in the mixer. Mix the honey and oil into the very warm water. Pour mixture into bowl and place mixer using dough hook on stir for about 2 minutes. Stop mixer. Add the rest of the flour, then set mixer to stir until the dough pulls from the sides of the bowl then stop mixer for 5 minutes. After the 5 minutes, go to speed 2 for 12 minutes. On a lightly floured surface shape into a ball Place in the refrigerator in a lightly sealed container coated with olive oil overnight or up to three days.

Remove 3 hours before panning
Remove from the fridge and flatten then fold, then shape into a ball using wet hands.
Makes a 16-18” pizza or two 12” pizzas

Randy

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