Acorns: Canberra's Street Food

The story behind this particular exotic, gathered ingredient is that I was riding my bike to civic on the weekend and came upon a tree with a lot of seed pods underneath it.

I did guess they were acorns, as they look exactly like the acorns from children's books especially when they still have their little hats! I broke one or two open and inside was a lovely beige coloured nut with a texture a little like macadamia. They didn't taste all that good though, but I did have a hunch there may be some way of processing them to be edible (if squirrels can eat them, why not humans!). Thus I took a bike pannier full home to investigate further...

It turns out they were in fact acorns and that they are actually edible with a bit of processing. Without processing the tannins in them are poisonous in large enough quantities, so be careful. They are however, a staple in Native American cuisine. Acorns come from oak trees, and apparently every kind of acorn is edible.

From initial investigations there are two kinds of acorn bearing oaks in Canberra. They are of course all introduced trees! The red oak Quercus borealis is probably the most common andhas acorns that are up to about 5cm long (see above). They have a lovely leaf which has kind of a lobe shape. I've seen these trees everywhere in Inner North, they are probably the most common oak in Canberra. Wattle St in Lynham has many good examples and they are pretty hard to miss with such large acorns scattered all around them and onto the roads.

The other species in Canberra is the Pin Oak Quercus palustis. This tree has much spikier leaves and much much smaller acorns. They are still edible however, and as they potentially have less tannins they may taste nicer. They are extremely fiddly though, so for the effort vs amount of nutmeat, I personally would say that red oak acorns are the way to go. If you interested though, an example of Pin Oaks can been seen on Hawdon St, Dickson.

Processing Acorns

It is necessary to process acorns to removed the tannins (a substance actually used to tan leather) to make them edible. This is a bit of a time-consuming exercise, so if there is any chance you may really like acorns for cooking, it is probably best to do a largish batch in one go. It would be possible to do the entire process and even cook something with them in one day, but in general it is easy to break it up into different steps that can be done in the evening while you do other things.

1. Kill any bugs in the acorns. It is necessary to do this straight after gathering. In the US there is a particular moth that lays it's eggs in acorns. It may also be in Australia, i'm not sure, so just in case do this step!

Lay all our acorns on a tray and heat in the over for 30mins at 120 degrees C.

2. Shell the acorns. You may have some kind of fancy device to do this that you use for other kind of nuts. I don't, so i just do it by hand with the help of a mortar and pestle. The shell is quite thin in comparison to most other nuts we are used to so it isn't as difficult as you may imagine...just time consuming.

3. Leach out the tannins. Boil acorns in water for 5-10 mins. Drain off the brown water and repeat 5 -6 times or whatever is needed to no longer have brown bitter water.

4. Dehydrate the acorns (do this straight after leaching or they will go mouldy). Put them in a low oven until they are completely dry, or in front of a heater.

And that is it. Your acorns are now edible. You can grind them to a flour or meal to use in cakes/bread etc, eat them on their own or even make veggie burgers from them. They make an interesting substitute for corn or almond meal, and it's gluten free! Stay tuned for some recipes....

Note: An alternative method is to grind the acorns before leaching. This is more in keeping with the Native American method. You can then put the powdered acorns in cloth and then in a bowl of cold water. This water needs to be changed regularly until the flour tastes sweet instead of bitter. This is a much slower process however, although is more energy efficient.

Another Note: Again i take no responsibility if you manage to kill yourself eating something i've suggested!