Sound very interesting to me. I'd like to her about this process.
GTG
I was inspired to brew a mesquite beer by an article in Zymurgy magazine written by a friend of mine. It discusses ethnozymurgy here in the Sonoran desert, and details brewing a beer with mesquite, and a cider with prickly pear fruits.
The process is pretty simple. It starts by collecting ripe dry pods. With most varieties of mesquite the pods contain 20-30% sucrose, and 10-15% other sugars, so it's not neccesary to malt or mash them, they simply need to be steeped to extract the sugars. It's a good idea to rinse the dirt off prior to using, especially if some of them were collected from the ground. They can then be spread out to dry, and then crushed when dry.
Since I wanted a more complex flavor than the raw mesquite provides, I chose to lightly roast the pods at 350F for 20-25 min. I think 10 min produces something similar to a light crystal malt, and an hour is similar to roasted barley. After roasting, I put them in a bucket and smashed them with a potato masher until the pieces were all under 1" long. At this point they could simply be added to a mash and treated like a specialty malt.
Since the sugar content of mesquite pods can vary quite a bit, it's a good idea to steep the mesquite and then boil down the resulting mesquite syrup a little bit. By measuring the SG of the syrup, you can easily adjust or repeat the results accurately for future brews. I steeped them for 90 min at ~150F before I was sure the SG had stabilized.
Even though it's not mentioned in the article, the author advised me that mesquite contains some aflatoxins that can cause some nasea or stomach pains if ingested in larger quantities. Just to be on the safe side, you can use bentonite clay as a fining agent to remove the toxins. Most homebrew stores carry it since it's used a lot in winemaking. It can be added to the mesquite syrup, or to the finished beer in the fermenter.
I'll update with results from the finished beer.
