50% Whole Rye, 50% Whole Wheat, Freshly Milled with 85% hydration
Today's bread started out as a couple of Tartine style whole grain loaves, but I didn't have the time to properly develop the dough, we had to rush out in the afternoon. I knew that the dough wouldn't elongate or hold its shape well enough for a free-standing loaf by the feel of it, so I put it in a couple of tins. But then, there wasn't quite enough dough for that -- or not enough wild yeast in the sourdough culture -- or too long a proofing in the cold garage -- and so these breads are a teensy bit flat.
- 500g Rye kernels, freshly milled
- 500g Wheat kernels, freshly milled
- 200g Wheat sourdough starter
- 20g Sea Salt
- 850g Water
Studies on Freshly Milled Grains
I continue to look at studies that talk about the advantages of freshly milled grains for nutrition. Curiously, the studies are ambiguous about the benefits of storing flour before use in baking. Some earlier studies suggest that when flour is stored, it bakes better bread (Chen). Later studies, however, have found exactly the opposite (Sur). From what I've seen, the studies do not properly specify the extraction of the flour they use as control. Most of them assume white flour, i.e. flour with bran removed.
There is also some discrepancy in studies which look at the changes in lipids of stored flour. One study says there is little hydrolysis (Clayton); another says there is lots (Arunga).
It would seem that there is definitely a change in the lipid structure of stored whole wheat flour. But flour that has its germ removed, is not going to experience a lot of change in lipid structure, because the lipids are already mostly removed. Whole grains will see the largest change.
Sur reported that storage of flour will deplete most of the nutritional parts of the grain: Protein, gluten, sedimentation value, starch and crude fat decreased during storage. Wennermark noted the degradation of vitamin E during storage. Chen showed that total glutathione was diminished; Sosulksi said that the phenolic acid levels fell; and Leenhardt showed that carotenoids lost their anti-oxidant properties the longer flour was stored. All of this tends to fall into the "duh" category. It seems self-evident, before you even begin the study.
There is one surprise, though: what did increase, when flour is stored, is the sugar content, and the free fatty acids of the flour, according to Sur's study.
But my research on freshly milled grain led me down another pathway. It is so easy to get distracted, when one sits to look into something. You know how when you go to a library, and you are looking for a book but find another book on a nearby shelf that leads you into a different topic, and its all serendipity? Internet research is like that, but its multiplied by a huge factor, since everything is interconnected. There's no end to it. That's why I can write about nothing but bread, every time I make it, and still learn something new.
I Googled "Fresh milled grain" or something similar, and after a couple of hours I discovered I was reading reports on the fumigation of stored grain. Which made me curious about how grain is protected against insect damage during storage in our country, and others; and how do organic growers of grain store their grain to keep pests away?
In the late 1930's, Mackie discovered that Methyl Bromide protected stored grain against pests (well, Minett says LeGupil stumbled upon this fact in France even earlier, but Mackie can take the blame on this continent). This was a boon to grain handlers: they could regularly spray their silos that were full of grain with the methyl bromide, and after 48 hours, most bugs were dead. And very little bromide was absorbed into the grain (supposedly). Unfortunately, we did not know then that the widespread use of methyl bromide was a contributing factor to ozone depletion. With the Montreal Protocol in 1989, methyl bromide began to be phased out.
I was not surprised, knowing how Canada has dragged its feet on other environmental issues, to learn that it has not entirely disappeared. It is still widely used in the US, too. Since 1989, Canada's grain handlers have been introducing other fumigants, but methyl bromide is still in use, here and there.
Meanwhile, there have been studies (Starratt) that concluded that the DNA of grains are methylated during storage and fumigation with methyl bromide. While Starratt found the guanine of the DNA was disturbed, another study (Minett) found that the amino acids histidine, methionine and cysteine reacted with the fumigant. The concern was that these flour proteins are involved in breadmaking, and this might affect loaf volume. Loaf volume was found to be affected when levels of Methyl Bromide were applied at 4-20x the commercial values of methyl bromide application. At levels below 2000mg/h.l, seeds can recover from methyl bromide fumigation, although a percentage will not germinate; at levels above this, all germination ceases. We do not know how fumigation may be involved in human cancers, but there have been suspicions.
So if we shouldn't use Methyl Bromide, what should we use to protect our stored grain from insects? In Canada, at least, some of the older solutions (ethylene dibromide, hydrocyanic acid, carbon tetrachloride, ethylene dichloride, carbon disulphide -- the dangers of which have been shown by scientists like Jagielski and others) are now utterly banned.
Bell reported there is no single solution, but rather an increased use of "chemical cocktails comprising methyl isothiocyanate-releasing compounds…" His list of fumigation chemicals includes
- sulfuryl fluoride
- carbonyl sulfide
- ehtyl formate
- methyl iodide
- methyl isothiocyanate
- methyl phosphine
Nowadays, according to Fields, our best defence against pests, when sprayed directly on grain, that is already infested:
- malathion (at the rate of 1.6 kg/t grain)
- diatomaceous earth (at the rate of 100-1000 ppm)
There are other chemicals at use to fumigate empty bins or packaged product, that supposedly never touch the grain itself. These are protectives:
- pyrethrins + piperonly butoxide
And there are also poisonous fumigants, which are often augured into bins along with the grain, and the grain is left a couple of weeks or more until all the bugs are dead, and then the silos are aired out. These are preventatives:
- phosphine (usually aluminum phosphide pellets; or gaseous phosphine)
- carbon dioxide (as a gas, or as dry ice), often used along with heat treatment
As for other products being tested against pests: quite often one finds studies that trial essential oils from various mint (Weaver, Bekele) or sage (Dunkel) or basil (Jembere) as fumigants. Some of these oils or crushed leaves work remarkably well against some pests.
According to Lisa Weasel, in her book "Food Fray: inside the controversy over genetically modified food" (2008), Bacillus thuriengensis (Bt) is a bacterium which can be sprayed on crops. Different strains of the bacteria will target different insects in their larvae stage. Rachel Carson, in her groundbreaking book, Silent Spring, said that Bt was an example of an environmentally friendly way to control pests. Since the 1950's, it has been used by organic farmers as a protection against moths and butterflies.
Weasel goes on to say that scientists at Monsanto have figured out precisely which genes the Bt bacteria use against pests. They have spliced those genes onto the DNA of some plant seeds they have genetically altered and patented. Recently this has caused a bit of an uproar in India, where Bt eggplants were first introduced, then withdrawn, then re-introduced, then boycotted, in the Indian food supply. Bt cotton is commonplace now; but is it wise to put this insect-killing protein from bacteria inside our food?
I think it is safe to say that so far, no one knows, and as Weasel points out, Rachel Carson would probably not approve.
Moths in your flour
I've recently met 3 different people who once bought their flour at Arva Flour Mills, but no longer do so because they said they found the flour contained moths. "It could have been an isolated incident, they could have got into the flour after I got it home, I don't know," I am told. "But I don't buy there any more."
Moths in flour are a concern, of course. Nobody likes to throw out flour that seems infested. Nobody likes to bring bugs into the home that can destroy food and clothing
But ask yourself why there are no moths in the white flour you buy at your local grocery store. What has it been fumigated with, stored in, shipped in, to get to your kitchen pantry and remain free of life?
Results of this Bread
Not my best bread, not by a long shot.
It still tastes good, though. Even if the crumb is a bit too moist and cake-like, even a bit gummy in texture.
Notes to Myself
- Here are a few of the references I've used here:
- Chen, X. and Schofield, D. (1996) Changes in the glutathione content and breadmaking performance of white wheat flour during short-term storage. Cereal chemistry. 73(1) pp. 1-4
This study sought to explain why breadmaking ability improved with stored flour, as opposed to freshly-milled flour, by looking at glutathione levels. In the first 10 days of storage, the free-reduced form of glutathione fell from 149 to 85 nmol/g of flour, but this could not be explained by an increase in the free oxidized forms, nor an increase in the forms of protein-glutathione mixed disulphides (because these levels fell too). They could not explain the drop in glutathione. It is, however, suspected that the drop in glutathione is involved with the improvements in breadmaking performance. This study quoted Kent, N. (1983) Technology of cereals with special reference to wheat, 3rd ed Oxford: Pergamon Press., for a report on how breadmaking improved upon flour storage.
On the contrary to the above study, which assumed that breadmaking ability improved with the aging of flour, this study found that "loaf volume of breads decreased during storage in both sound and sprouted flour but the mean percent decrease in loaf volume was more in stored sound flours.". "Protein, gluten, sedimentation value, starch and crude fat decreased during storage in all samples." What increased were "total sugars and free fatty acids" during the storage of 135 days.
- Clayton, T. and Morrison, W. (2006) Changes in flour lipids during the storage of wheat flour. J of Sci of Food and Agriculture. 23(6) pp. 721-736There is no loss of lipids if the flour is stored at 15 degrees C, but slight losses at higher temperatures. Mostly the lipids remained constant, but there was some hydrolysis of glycerides, and so an increased amount of free fatty acids the longer it was stored. The fatty acids were not degraded by enzymes.
- Arunga, R. and Morrison, W. (1971) The structural analysis of wheat flour glycerolipids Lipids 6(10) pp 768-776Identified 23 classes of lipids in flour. Reported previous studies that indicate "enzymic hydrolysis of glycerides occurs during the storage of cereals and flours, and enzymic oxidation of free fatty acids and monglycerides occurs during aerobic dough mixing." Such changes do take place during germination, but since milling is a different process, contamination from bacteria and moulds may change what happens.
- Wennermark, B. et al. (1994) Improved vitamin E retention by using freshly milled whole-meal wheat flour during drum-drying. J Agric Food Chem 42(6) pp 1348-1351This study found 42% more alpha-tocopherol or Vitamin E in processed food when it used freshly milled wheat rather than stored whole wheat flour.
- Sosulksi, F. et al. (1982). Free, esterified, and insoluble-bound phenolic acids 3. composition of phenolic acids in cereal and potato flours. J Agric Food Chem. 30(2) pp. 337-340This study found that the total phenolic acid content of wheat flour fell from around 71-87 ppm to 26 ppm, over six months of storage. Many of the phenolic acids were not properly identified in this study.
- Leenhardt, F. et al. (2006) Wheat Lipoxygenase activity induces greater loss of carotenoids than vitamin E during breadmaking. J Agric Food Chem 54(5) pp. 1710-1715This study found that major carotenoid losses occurred during kneading, and depended largely upon the amount of lopoxygenase (LOX) present -- which was determined by cultivar. The more carotenoid pigment, and the less LOX enzyme, the more carotenoids (unsaponifiable antioxidants) were preserved. Moderate kneading also resulted in higher vitamin E retention.
- Minett, W. et al. (1976) Methyl Bromide Fumigation I. Effect of high dosages on breadmaking quality and germination of wheat. Cereal Chemistry 53(1) pp 41-50.
A good article for background info on methyl bromide fumigation related to bread.
- Starratt, A. and Bond, E. (1988). Methylation of DNA of Maize and Wheat Grains during Fumigation with Methyl Bromide. J Agric Food Chem. 36(5) pp. 1035-1039.This study concluded that Methyl Bromide affected in particular the guanine residues in the DNA of grains that were fumigated. Since Methyl bromide is a mutagen, the potential for mutation is substantial.
- Bell, C. (2002) Fumigation - the few remaining compounds. Phytopharasitica 30(1). pp.3-6
I thought I was obsessed with strange stuff. Bell spent a lifetime researching how bugs are eradicated from grain storage.
- Fields, P. and White, N. Avoid Surprises at Delivery: Good Grain Storage Practices. Agronomy Update, Red Deer, Alberta.Fields also did quite a bit of research used by the Canadian Miller's Association. See, for example,
Canadian National Millers Association (2007) Comparative Evaluation of Integrated Pest Management, Heat Treatments and Fumigants As Alternatives to Methyl Bromide for Control of Stored Product Pests In Canadian Flour Mills
- Weaver, D. et al. (1991) The efficacy of linalool, a major component of freshly-milled Ocimum canum Sims (Lamiaceae), for protection against postharvest damage by certain stored product Coleoptera. J of Stored Products Research. 27(4) pp. 213-220This study used linalool, the oil of a certain mint, to spray on grain in Rwanda to reduce pest damage.
- Dunkel, F. et al (1998) Fumigant properties of physical preparations from mountain big sagebrush, Artemisia tridentata Nutt sap. vaseyana (Rydb.) beetle for stored grain insects.This one used a sage product as a fumigant, similar in action to methyl bromide.
- Jembere, B. et al. (1994) Products derived from the leaves of Ocimum kilimandscharicum (Labiate) as post-harvest grain protectants against the infestation of three major stored product insect pests. Bulletin of Entomological Research 85(3) pp. 361-367This study used ground leaves and essential oils of O. kilimandscharicum as a pesticide on stored grain, to determine its feasibility for its use on stored grain in developing countries. The bugs tested were Sitophilus zeamais, Rhyzopertha dominica, and Sitotroga cerebella. All were killed after 48 hours.
- Bekele, A. et al. (1996) Evaluation of Ocimum suave (Wilid) as a source of repellents, toxicants and protectants in storage against three stored product insect pests. Int J of Pest Management. 42(2)The use of linalool again, this time using O. suave.
- Dudley H. and Neal P. (1941) Methyl Bromide as a fumigant for foods. J of Food Science. 7() pp. 421-429.This study reports that since 1938, methyl bromide was used as a fumigant, when Mackie and Hawkins discovered it eradicated grain pests. Most grains did not absorb much bromide, but milled grains did.
- Jagielski, J. et al. (2006) Residues of carbon tetrachloride and 1,2-dibromethane in cereals and processed foods after liquid fumigant grain treatment for pest control. Pest Management Science. 9(2) pp. 117-126Halogenated hydrocarbon 'liquid' or vapourous fumigants cause carbon tetrachloride and ethylene dibromide residues to remain after fumigation and even up to 1 year after storage and processing. This study measured the amounts in bread and made some recommendations.