Stupid Buttermilk

I had most of the quart of “cultured” buttermilk left from making those yummy cinnamon rolls and thought I’d use some of it in my mashed potatoes last night. I poured about a cup into my 2-cup Pyrex measuring cup along with some butter and popped it in the microwave for 1 minute. (I love my Pyrex measuring cups - I’m a proud owner of the 4-cup as well. Someday I hope to own the 8-cup but am not sure if I’m ready for such magnificence)

While regular milk, half-and-half, or even cream wouldn’t have minded this heating method, the buttermilk had other ideas. It rebelled - and not just by curdling but by completely separating into clear liquid with a big white jabba-glob floating on the top. Ick!

After I dumped the buttermilk curd and whey down the drain, I slightly, slowly warmed another cup, mixed in 3T of melted butter, some salt and pepper and added the whole mess to three steaming pounds of peeled, cubed, cooked and drained taters. I like my mashed taters “homestyle” (which means lumpy) better than the smooth style although I do own a ricer (it is a major pain to clean but does make super smooth, string-free sweet potato puree for sweet potato pie).

I grabbed my potato masher and began, well, mashing. As I mashed, I noticed white cheesy strings forming in the potatoes. That stupid buttermilk separated again! Although the potatoes were delicious and no one else noticed the string cheese addition to my perfect mashed tater and meat muffin dinner, it bugged me.  Why was the darn buttermilk so sensitive to heat? I decided to find out.

Investigation in my Cook’s Illustrated (Sept/Oct 2004 p.30) taught me that buttermilk does not like being heated above 90 degrees. CI recommends leaving it on the counter to reach room temperature or microwaving on 30-40 seconds at 30% power stirring once or twice. These were good tips but didn’t tell my WHY the buttermilk curdled, so I continued my research.

Buttermilk is thicker, tangier tasting and more acidic than regular milk due to a higher lactic acid content. Regular milk has a pH of 6.7 while “traditional” buttermilk has a pH of 6.4 and “cultured” buttermilk has a lower pH of 6.0 (neutral pH is 7, acids are lower than 7 and bases are greater). In traditional buttermilk, lactic acid is allowed to form naturally through fermentation of the lactose in the milk. Cultured buttermilk has lactic acid added and is cheaper to make and more commonly found in the grocery store. This lactic acid is what makes the milk thicker. It is thicker because the milk has ALREADY BEGUN to clabber (curdle or separate). Bingo! I had my answer.

By the way, if you have a recipe calling for buttermilk and don’t happen to have any buttermilk, you can make your own by adding either vinegar of lemon juice (acids) to regular milk and letting it sit for about five minutes to complete the process. The ratio is typically 1T acid to 1c milk.

Despite the word “butter” in its name, buttermilk is nearly fat free (less than 1% milkfat). The name came from the fact that all of the cream used to make butter had been removed.

AND!! I was very excited this morning to find a source for REAL buttermilk. The good people at Bergey’s Breadbasket in Chesapeake get it in regularly and will set some aside for me next week! (PS – they make AWESOME baked goods – cinnamon rolls, yeast rolls, pies, biscuits – as well as growing their own produce available for sale)  Check them out!
http://www.bergeysbreadbasket.com/