Just reviving this topic a bit, I know its been talked about before but I am interested in knowing how this subject has changed over time and if anyone has some new insights. I am new to DIY soylent and I have begun building my first recipe. I spent a fair bit of time looking at other recipes and trying to understand the methodology and choices that other have made so far. One issue that has cropped up was the adverse affects of Phytic acid to mineral bio-availability and digestion of other elements such as protein.
From what I see when reading through recipes, the majority of people seem to completely ignore the issue of Phytic Acid, or at best they overload on minerals in a hope to cover up any chelating that may occur. In Australia, where I am from, the majority of the most popular recipes all contain Oats in one form or another, it seems to be the go to cheap carbohydrate source in this part of the world.
I found a really interesting article that went into great detail about Phytates and Phytase, how they all work, where it is found, and how it affects our nutrition.
Previous threads have dealt with this issue before but there appears to be a lot of misinformation in the comments and responses in these threads. Especially to do with alternatives to oats.
Some alternatives I have heard mentioned include Rice Flour and Almond Flour, but Brown Rice is actually higher in Phytic Acid and Almond Flour is not much better than Oats. Most people say that soaking these grains is enough but that is not the case, it wont eliminate much of the acid at all, see this:
One popular alternative is Masa Harina, many people assume that the lime water processing or nixtamalization used in the creation of Masa Harina is enough to reduce phytic acid, but in actual fact, only around 20% of the acid content is reduced (http://www.phyticacid.org/corn-phytates/). When you compare the base phytic acid of oats to corn, Masa Harina may in fact be a worse source of phytic acid than oats.
Malted Barley has been mentioned before as well and I think that this is probably our best bet as the malting process is shown to eliminate approximately 57% of phytic acid in barley, leaving only around half a percent of phytic acid present.
I would like to hear some feedback from others who has tried malted barley, what sort of nutritional information is available on it, and what is the best form for milling to a flour (crystal malt has been mentioned before but what is it).
Also if I have overlooked any possible carbohydrate sources that would be low in phytic acid with good taste and nutritional profiles, I am very open to suggestions.