I have just started a new Blog and built a new website … Its an attempt to get to the nub of growing heritage grain. Although the project – grainoftruth.org – is about carbon sequestration, strengthening communities and increasing bio-diversity (to name three other elements) it is mainly, for the moment anyway, about Nutrition.
Our nation is roughly 60% overweight and a large % of those people are obese. Wheat, as bread, as additives and derivatives is 20% of our diet. Wheat is the most traded food source in the world. So, taking these three points, it makes sense to do everything we can to improve the nutritional content of wheat flour. The step i’m talking about here is using Fresh Flour in everything we bake. Let me explain (more reports and info to follow) by giving you some snippets from a report by Judy Campbell, B.Sc., Mechtild Hauser, and Stuart Hill, B.Sc., Ph.D., P.Ag.,1991.
If you haven’t got the time to read the below paragraph from the report heres a few key points:
2 weeks storage of flour is considered the outer limit of nutritional quality
Lots of great nutritional elements – Vitamin E, a whole raft of Vitamin B’s (great for cell building) are changed very quickly by that fickle element Oxygen
Within 2 days (other reports site hours) the active parts of flour – the bits that are alive – become rancid
ADVANTAGES OF FRESH FLOUR
Because grains contain only about 12% water (or about 0.6 water activity), they are not predisposed to spoilage. However, grinding removes the protective layers and endangers the grain’s biological stability. Deterioration of sensory and nutritional qualities depends on storage conditions, such as temperature, humidity, oxygen concentration, and light exposure. The lower the water activity, the lower is the loss of vitamins (Munzing, 1987). For example, a vitamin E loss of only about 23% occurred after a 13 months of storage at a 0.6 water activity (Rothe 1963, Plasch 1984, Pelschenke 1961). In order to reduce oxidation of Essential compounds and the development of rancidity, many authors recommend storing ground flour for no more than two weeks (Solder 1984, Bruker 1984, Schnitzer 1986, Schnitzer (no year), Thomas 1982, Thomas 1986, Koerber 1986). Antioxidants present naturally in grains (vitamin E and lecithin) help prevent oxidation of the fatty acids and the associated rancidity only for a limited time, and under ‘favourable’ conditions.
Glutamic acid decarboxylase, the most sensitive enzyme in the grain, is used to indicate the health of the grain. When heated or exposed to increased humidity, even under ‘favourable’ conditions, it losses activity very quickly in wheat. It was found to be even more sensitive in rye (Muzing, 1987). The B vitamins are liable to be destroyed by light and air, and it also seems that other substances, still unknown, are quickly destroyed (Aubert, 1989). Other deteriorations include denaturation of lipoproteins, phospholipid hydrolysis, auto-oxidation of unsaturated fatty acids of phospholipids, polymerization within lipoproteins, browning, Maillard reaction of amino groups from phospholipids and aldehyde groups from sugars, and carotene and aroma losses (Lea, 1957; Thomas, 1976).
Lipids in milled wheat are much more susceptible to enzymatic degradation, because enzymes are incorporated into the flour with fragments of bran and germ and with microorganisms from the surface of the grain. Associated with lipid deterioration are losses of carotenoids and vitamin E (Galliard, 1983).
Different ecological standards for flour storage set limits of 15 to 60 days (Picker & Pedersen, 1990), although rancidity has been detected as early as 2 to 14 days after milling (Larsen, 1988). Nutrient analysis studies are required to determine the exact nutrient losses accompanying the development of rancidity and thereafter.