Importance of Water Content in Butter?.

In my baking I use store brand unsalted butter. I have just switched stores and have found that this new one sputters alot when melted. I believe this is evidence of water content in the butter(though i have never understood this because i thought butter was 100% dairy fat?)Except for the making of puff pastry(I'm guessing here) does the amount of water in the butter- really matter for baked goods? If it does, I'm wondering why the FDA doesn't require that a butter's water content be listed on the packaging. I am more than chemistry-challenged, as you might guess from my baking questions, past and present. Thx much for educating me.

LeBec Fin


Diana W. January 15, 2019
It does matter...and I am getting sick of being manipulated. The butter does sputter and does not brown. Not a good thing if you are making Brown Butter Sugar Cookies. The butter did not foam, but developed scum on top of what looked like it was curdled. One and one half sticks of butter magically became 1 cup of melted YELLOW liquid after ONE HOUR of trying to brown it. I have been baking for many years and know what I am doing. No wonder younger women don't want to learn to cook...nothing is what it once was. Messes with your recipes, especially baking.
LeBec F. March 31, 2013
slaw et al- plse disregard my response above. i had not yet read the linked article. sorry.
Hilarybee March 29, 2013
smslaw is right--80% butterfat is the minimum required for USDA Grade A butter. If you look on the package, it will say what Grade the butter is. European butter like Plugra will list the USDA Grade and the grade it was given at production in its home country. You are unlikely to find anything lower than Grade A at a traditional grocery store--but if you buy Amish butter, it is ungraded and tends to have more water in it. Likewise, raw butter is not graded and will be less consistent. Small farms will not be subject to the same grading process as a large operation like Kraft or Land O' Lakes, and in some cases are omitted from the USDA grading process altogether because individual states license and monitor small family farms.
dymnyno March 28, 2013
Wow...did you ask a great question! Have'nt we all suffered from sputtering butter.
LeBec F. March 25, 2013
i think kbc might have had a pc invasion of the little ones?
sfmiller March 25, 2013
This article analyzed the percentages of fat, water, and milk solids in different butters, then tested several recipes with different butters to see what practical difference it made. The results are interesting. The variations in moisture content seem quite small, but even small variations can produce significantly affect results.
dymnyno March 29, 2013
I read the same article by Kim Severson. Basically the higher the fat content the dryer the butter. Strauss which is my favorite butter has a fat content of 82%.
smslaw March 25, 2013
All butter you buy at the store has between about 15 and 20% water (80% fat is the legal minimum.) Unsalted supposedly has a bit less water. I wouldn't assume that a store brand has less fat content than a national brand. Almost all have the minimum 80% fat. Higher fat content makes pastry flakier. The difference between 15% water and 20% water can be significant. I'd check with the manufacturer and ask about specific moisture content. Plugra, for example, says it is 82% fat.
The M. March 28, 2013
We agree with smslaw's answer here.
LeBec F. March 31, 2013
slaw, this is v helpful but it doesn't sound like 15% or 20% is a likely scenario here does it? it sounds more lkely to be 18% or 20%,and even then, not as big a deal except in puff dough or pie dough. (Not so important in cakes/breads/cookies)yes?
sdebrango March 25, 2013
I just bought a store brand of unsalted butter to try it, and I found the same thing.I made buttercream and it ended up in the trash, there was too much water in the butter, it broke and I couldn't get it to come together, ended up in the trash, Thats the last time I deviate from the butter I always use. I wish I had an answer, just wanted to commiserate.
Recommended by Food52