Acorns

I have a lot of oak trees.  Mostly I have ones that yield red acorns, but I have some white oaks, too.  And near my suburban house, there's a subdivision with about six Shumard oaks planted at the front. At the office park where I work, there are dozens of water oaks planted at the edge of the parking lots and in small plant islands in the lots themselves.  Because the oaks fall on pavement, they are easy to find and if not collected by me or the squirrels, they get crushed by cars and/or vacuumed up by the landscapers for dumping in an inert landfill.
 

Oak trees in the fall are beautiful--at least some of them are.  Some have leaves that turn a drab brown.  The picture at left shows some of the oaks I'm talking about, in addition to other trees--hickories and dogwoods...maybe a few others.   However, I want to focus on oak trees for food rather than ornamentation.

All species of oaks produce edible acorns, and all of them have too much tannin in them to be palatable straight from the shell.  I have tried with a variety of oaks: red, Georgia, Shumard, and white. The whites are close, but still too bitter--and they are reported to have the lowest tannin level.  Apparently tannin matters to some degree to deer, as well; they like white acorns the best.

For humans, something needs to be done.  Many sites and books suggest using water to leach the tannin out.  This book by Samuel Thayer has an extensive discussion of processing acorns.  However, there are many subtle variations. Generally, 'most everyone I've read recommends several changes of water at temps from room to boiling.

I have been picking up acorns for years and doing nothing with them.  Although drying them for a while is recommended, there is a difference between processing and indifferent procrastination.  Now is the time of harvest; later is the time to figure out what to do with them--so I have told myself for the last several autumns. My co-workers think I'm a little odd for picking up handfuls at the office.  So far, I have nothing to show for the effort.  Finally, I decided to try a pilot project.

Acorns are often targeted by insects; Thayer's book covers this in detail and has recommendations for identifying bad acorns easily when processing a lot. For my pilot project I didn't need to stress about it.  I picked up some newly-dropped acorns earlier this week. I cracked three and one was good (for what it's worth, a much greater proportion of the ones I've cracked from the office park have looked good; they are very clean).  I diced the Shumard into about six pieces, put the chunks into a coffee cup, filled it with water and microwaved it for a minute--not enough to make it boil, but enough to get it to simmering temperature.  Every 12 hours or so I changed the water for a couple of days.  Each time, the water was less tan-hued by the time I changed it.

After several water changes, they were edible--the bitterness was (mostly) gone.  This is less than an epic finding; all I have done is verify what others have reported.  However, it is encouraging that it's a viable process, if somewhat labor-intensive.  The taste of the nut meat itself was pretty bland.  I don't know if it would be any different if I had dried it first, but during the leaching process I assume it'd rehydrate to whatever extent it could--so that might not matter much.

I'm not sure I will do this on a broad scale, but I certainly have the acorns available if I want to.

Update:  The above obviously depicts beginner-style experimentation with the concepts.  This blogger shows the results from decanting and leaching--the latter being quicker, given sufficient equipment to process the nut meats before leaching.