After a disastrous attempt at making a cake using quinoa flour, I abandoned the bitter, grassy stuff in favor of blends of other gluten-free grains, including buckwheat, teff, brown rice, millet and tapioca. I never thought I would go back to quinoa until a sample of a cookie made with quinoa flour changed my mind.
When I first abandoned gluten in my diet, about four years ago on the recommendation of my nutritionist who was trying to address chronic illness with diet, quinoa seemed like a natural fit for my baking. But because quinoa flour is so bitter, earthy, and grassy, it easily overpowers the other ingredients in a recipe. This is due, in part, to saponin, a toxic glycoside that coats the outer layer of the quinoa seed. Saponin can be washed off or removed via abrasion, and usually is before it is sold commercially to consumers. But the washing isn't always thorough enough, and some trace of saponin remains. There's also phytic acid, which gets in the way of the absorption of minerals in the digestive tract - this is removed to some extent by heat treating but requires fermentation and sprouting to more thoroughly break it down.
The saponin isn't a problem if you are buying quinoa seeds to use in savory recipes. All you need to do is wash the quinoa again, as you would certain kinds of starchy polished rice. But milled as flour and included in a recipe, this not-quite-washed-all-the-way grain becomes a gatecrasher and ruins just about everything it touches.
But there's an utterly simple solution to this, a solution that not only takes care of the bitterness and grassy flavors, but also inactivates trypsin inhibitor, (warning, long explanation ahead) a compound that reduces the bio-availability of trypsin, an enzyme which helps hydrolyse proteins (this is especially important for lysine, an amino acid that is vital to human health and is most commonly found in beans and dairy but occurs in quinoa in high levels).
The oven. That's the solution.
And quinoa is worth it. Its protein and fiber content is higher than wheat, it has fewer carbs than wheat, and it is packed with vitamin and minerals. Its fat content is slightly higher than that of oats and nearly 3x that of wheat. It works like pastry flour in baked goods, especially when combined with other flours. Trust me, baking the quinoa may be an extra step, but it is simple and easy and will make your baked goods better tasting and better for you.
You don't need to toast or pay attention to quinoa while you are heat processing it, but heat process it you must.
Here's all you need to do to make baking-ready quinoa flour:
- Preheat oven to 212 or 215 F (100 C)
- Empty out bag of quinoa flour onto as many sheet pans as you need, preferably onto a new piece of parchment paper
- Make sure the layer of flour is no deeper than 1/4"
- Place in preheated oven for two hours
- Remove from oven. Allow to cool. Place in bags
- Store bag in freezer for up to 8 months if you are not planning to use flour soon. Whole quinoa flour is relatively high in fat, making it vulnerable to oxidation and rancidity. Freezing will extend the shelf-life.
- Use as you would any other gluten-free flour
For further reading on quinoa, check out this interesting literature review from a 2009 article from the Czech Journal of Food Science.
UPDATE: Since I wrote this post, I have worked with a quinoa flour that was "triple washed" before milling. And guess what? It was still earthy, soapy, and grassy. All quinoa flour needs to be toasted, unless it is pre-toasted.