Bad Butter Cookies - Why?

Today I made another batch of butter cookies, with butter creamed for two minutes and flour mixed in for two minutes. After baking, the cookies were relatively flat - flatter than I've been making lately, using six minutes of creaming and 2-3 minutes of mixing. Worse, a few of the cookies show a little pitting, even on the William-Sonoma Goldtouch Commercial Cookie Sheet. What's wrong, exactly?

My last post reported I had some problems with butter than had been warmed to 75 degrees, then cooled back down. I baked the cookies, but hadn't done a taste test at the time of my last post. I will confirm that they didn't come out too badly, but they were in fact slightly denser than the cookies I'd been making. By denser, I mean that they were slightly flatter. The ones on the Wilton pan spread more than with the six-minute cookies, but even the ones on the Goldtouch sheet were slightly flatter, though they didn't spread much. The denseness meant that they were less crumbly when I bit into them, maybe slightly harder.

The cookies I baked today will be even more in that direction. The cookies on even the Goldtouch sheet spread.

Today I had no problems with the butter. I set it out, its temperature went up to 70.5 which is not high, I cooled it to 66 (a little too cool), and then it warmed again to 70.5, and I then cooled it again to 68.4, at which point I made the cookies. A little more messing around with temperature than I wish, but not all that much fluctuation, and definitely not to warm temperatures.

I was very interested in the measurements I made after creaming and mixing in flour today. I am going to give results from a couple of days ago, followed by the result today.

Start temperature:
68.9 - 68.4

End temperature:
72.5 (change of 3.6) - 69.1 (change of 0.7)

Weight of one cup of butter/sugar after creaming, minus weight of the cup:
227 - 197

Increase in volume through creaming:
13.7% - 31.0%

Weight of one cup of dough after mixing, minus weight of the cup:
234 - 247

Increase in volume through creaming and mixing:
3.9% - 0%

The first thing is the temperature of the butter in the experiment. Both started out at about the same temperature, but the butter that had been warmed to 75 degrees, then cooled, for some reason wound up 3.6 degrees higher after only two minutes creaming, while the temperature that had not gotten overly warm only went up 0.7 degrees during mixing. After having done many experiments now, I can say that 3.6 degrees change is a pretty large change. I don't know why it would be different, but over-warming the butter, even to 75 degrees, definitely makes a difference.

My last post said that the volume increase I found with the butter that I'd warmed to 75 degrees, then cooled, was far less than what I'd found and posted for the same two minutes of creaming on January 31. Well, I made a mistake - I just now realized that the volume increase in the January 31 posting was for one cup of butter and sugar each creamed in my small mixing bowl, but now I'm creaming two cups of butter and sugar each in my large mixing bowl. The creaming always goes faster in the small mixing bowl.

However, comparing apples to apples, my last experiment to today's experiment, the butter that had not been warmed too much increased in volume more than twice as much during creaming as the butter that had been over-warmed, then cooled. The difference between 13.7% and 31.0% is quite a large one. I would say that it is related to what happened with the butter the other day when it went up to 75 degrees temporarily before I creamed it.

So were the results today better? No! So what's that say? I'm not sure yet.

After I mixed in the flour, the weight of a level cup of dough was actually more, yes, more, than I measured when I just mixed melted butter with sugar and flour. I recorded the volume increase through the mixing step today as 0%. I can add that the dough I formed into rolls for the refrigerator had a very solid feel, and had a consistency like light-weight clay. That seems to bear out the lack of air in the dough after mixing.

And what happened when I made the cookies with 0% volume increase after mixing flour? They were flat, and some were pitted, that's what!

Very interesting. The cookies that had less air in them from creaming - and much less air than when I cream for six minutes as I had been doing recently with good success - had more air in them after mixing the dough, and baked to better cookies than the ones that had more air after creaming but less air, actually no air, after mixing the dough.

I am tentatively concluding that the amount of air left in the dough after mixing is quite important. What I want to find out is whether repeating this experiment with butter that has not been overwarmed keeps turning out the same way, in other words, does mixing in the flour at around 69 degrees result in all the air being chased out of the dough. That would hint that it's important to mix the flour into slightly warmer butter. But I can't come close to being sure of that until I'm pretty sure that this happens every time. When I cream for six minutes, the temperature always goes up higher during the creaming process, so I am mixing the dough into somewhat warmer butter. With the butter I over-warmed and then cooled but used the other day, the temperature went up more than usual during two minutes of creaming, so the flour was also mixed into warmer butter, and the result was better (though not ideal). It will be fascinating if I find the same thing in a repeat experiment!