Last week I introduced you to five experts on the issue of properly preparing grains, by soaking or sprouting. This week you’ll hear where the drama all began. (Catch up on all the soaking grains research here.)
You can read Dr. Teri O’Brien’s article and my question that started the whole thing here. Dr. O’Brien is a grain scientist Ph.D. from Australia.
We proceeded to have an email conversation that really got me digging about the whole “soaking grains” and phytate/phytic acid issue. I suddenly mistrusted everything I was reading from the Weston A. Price Foundation and wanted to see the research for myself.
The good doctor addresses this quote from Nourishing Traditions that I directed him to (any emphasis is mine):
Phosphorus in the bran of whole grains is tied up in a substance called phytic acid. Phytic acid combines with iron, calcium,, copper and zinc in the intestinal tract, clocking their absorption. Whole grains also contain enzyme inhibitors that can interfere with digestion. Traditional societies usually soak or ferment their grains before eating them, processes that neutralize phytates and enzyme inhibitors and in effect, predigest grains so that all their nutrients are more available. Sprouting, overnight soaking, and old-fashioned sour leavening can accomplish this important predigestive process in our own kitchens. Many people who are allergic to grains will tolerate them well when they are prepared according to these procedures. (Nourishing Traditions, Sally Fallon Morell, Pg 25)
“This is a bit confused: in the bran of the dry grain, the phytic acid is actually present as crystalline deposits( called “globoids”) contained within the highly specialized protein bodies that are rich in arginine. These reserves are extremely insoluble forms of the Ca Mg salt of phytic acid, which is indeed rich in phosphorus, and contains traces of iron and probably the other ions mentioned by her.
Until this material passes the stomach, where it is exposed to strong acid (pH 1 hydrochloric acid) these Ca-Mg phytates are insoluble. Once through the stomach, the acidity will tend to release the phytic acid as free phytic acid, and the previously bound minerals. Phytic acid has 6 atoms of phosphorus on it and a useful precursor of a lot of lipids, but there is very little information on whether or not it can pass through intact cell walls in bran or not. And it may be that the phytic acid that turns up in digesta has come from damaged cells. There is a literature that suggests that as soon as the phytic acid reaches the small intestine where its acidity is neutralized, that it can now recombine with minerals and may make them indigestible again! If only things were simple! (Me: Phytic acid needs much stronger than a pH of 4, the recommended acidity for soaking, to release its minerals.)
Given that phytic acid is a precursor of certain lipids, it may be that it is capable of being absorbed in the gut somewhere, either with or without its load of minerals. As the free acid it would carry a very strong negative charge and would be difficult to absorb across the cell surfaces of the gut, but just how much it is rebound to minerals along the length of the gut, and would therefore find absorption easier, is not clear.
The presence and role of seed-based digestive inhibitors varies a lot with the type of grain, and mere soaking is unlikely to change that unless it is long continued. Fermenting the grain ( overnight soaking will get most grains beginning to germinate) starts up the processes whereby the embryo combines with the bran layer to release starch and protein digesting enzymes from both the embryo and the bran layer. These processes have been studied in great detail for wheat and barley. The embryo in all grasses so far studied absorbs the products of this breakdown of the starchy endosperm, as well as mobilizing its own reserves of high quality protein, but once again, the embryo cells are enclosed in a wall that is extremely resistant to digestion. If whole grain, cracked grain, or even pollard rich in embryos is added to the bread dough after soaking the contents of intact cells ( some can be broken by chewing) will not in general be attacked in the digestive track. However, any sugars (such as maltose) or amino acids (glutamic acid) that are still in the digesting soup of soaked endosperm have a good chance of being absorbed during eating as they will survive baking.
I know of no reason to suppose that the process of pre-digestion (partial) that accompanies prolonged soaking will “neutralize phytates and enzyme inhibitors “. What is important to understand is that prolonged soaking starts the grain germinating if it is intact or cracked, so we are now dealing with processes that accompany natural germination. 18 hours at 20C is sufficient to get soaked grain well on the way. (Me: This would mean flour wouldn’t be affected, as it could no longer germinate.)
Fermenting or soaking grains prior to cooking is indeed a well-recognized tribal behavior and strongly recommended by Bill Mollinson of Permaculture fame in his book on fermentation. When long continued, specialized bacteria often accompany the process and are capable of rendering a poor quality food material (eg., cabbage) into the highly nutritious sauerkraut, but a lot of the extra nutritive value comes from the addition of microbial protein that arises from the fermentation. (Me: soaking for only 12-24 hours doesn’t seem to fit the bill of actual fermentation.)
We could summarize it like this: prolonged soaking begins to transform a dormant seed into a growing one, and reserves that were perhaps very unavailable in the dry grain may be rendered a bit more available in a human digestive tract. After all, the grain’s embryo is starting to digest its reserves. But the devil is in the detail in this kind of discussion and unfortunately, the published literature on how the human digestive tract behaves, is not always helpful.”
Sally Fallon Morell
When I asked Sally Fallon Morell, author of Nourishing Traditions, for her response to the direct challenge to her work, she replied:
“I think if you go to Handbook of Indigenous Foods, you will find that soaking in acidic medium indeed reduces phytates. It also increases mineral availablity, lysine availability, and B vitamins. Aflatoxins and pathogens are reduced or eliminated. (I’ll share her sources, along with Dr. O’Brien’s specific thoughts on them, next week.)
For our take on grains see here.
There are many reasons to soak or sourdough grains–these processes not only neutralize phytic acid, but also enzyme inhibitors and lectins and seem to miraculously reduce the problems with gluten.”
Me: In summary, Sally Fallon promotes that whole grains are dangerous unless properly soaked in an acidic medium or sourdoughed.
“I wonder why one would go to a Handbook of Indigenous Foods to discuss anything about wheat (or any other cereal) since these plants have not been indigenous foods since perhaps 3000 years ago in the Middle East.
Wherever phytates are present in wheat in dry grains, they are not there as free phytic acid, but as the CaMg double salt as highly crystalline “globoids”. To dissolve those by acids requires quite an effort and a fair dose of acid: to drive Ca and Mg from phosphate groups I would guess you would need a pH of at least 2.5, easily achieved in the stomach at pH 1, but for example, 1% vinegar is only pH 4.5. I do not believe the lysine figure: lysine occurs as part of a protein that is also rich in arginine, and these are not in the least bit soluble in acids such as to release their amino acids. There are large, highly insoluble reserves of niacin in wheat called “niacytin”: I don’t know how resistant they are to acid digestion, but they would release only niacin, just one of the B-vitamins, not ” B-vitamins”. I’ll check on aflatoxins, which of course are not common in cereals but are a real threat from badly stored peanuts. They are not destroyed by boiling so I’ll be amazed if they are by soaking, but let’s see the evidence.
As for “pathogens”: what pathogens? Stored grain contains some remnants of fungi that lived on the starch released when the out bran layers died as the grain ripened but these are not pathogenic to the plant or to us.
I wish to make it clear that soaking is not the same thing as fermenting in my mind. Prolonged soaking may lead to fermentation starting since cracked or whole grains are not sterile, and fermentation for protracted times (several days) has the capacity to transform poorly digestible material into something that may be better digestible by a human digestive tract, but no microscopy has been done to see what happens in practice. Without the facts, speculation is idle.”
More next week on the hot debate, plus three takes on why white bread might be a viable option!
Here‘s a cool article on a restaurant that actually soaks oatmeal before cooking!
I’m pleased to participate in Fight Back Friday.