Flour folate

Folate deficiency The recommended dietary intake of folate has been increased (also protects against neural tube defects in the fetus), and additional folate is now added to flour (bread, pasta, and other products made liom flour)... 

Approximately 10 percent of the U.S. population40 had a lower folate level than that at which chromosome breaks occur.41 The recent decision in the United States to supplement flour, rice, pasta, and cornmeal with folate42 may reduce the percentage of the population with the deficiency. 

Several studies have demonstrated an association between plasma tHcy levels and extent of CAD in populations not exposed to fortification of flour products with folic acid, even after controlling for conventional risk factors (26,27). In contrast, Brilakis et al. (28) found no association between plasma tHcy and angiographic CAD in a North American population consuming cereal grain flour fortified with folic acid. Silberberg et al. (29) found an association between plasma folate and CAD independent of tHcy. 

A 6-month-old infant has been fed unmodified cow s milk supplemented with com flour. He was healthy except that he was severely anemic, and an X-ray of his wrist showed retarded bone development. His hemoglobin was only 4.5 g/dL, and he had an elevated serum alkaline phosphatase. He was treated with iron supplements, folate, and ascorbic acid to no avail. Then serum copper analysis was done, and it showed a level of 9 fig/dL (normal is 85-163 /ig/dL). Thereupon his diet was supplemented with copper sulfate, and he showed dramatic improvement. Address the following questions ... 

When foods have been enriched with vitamins, because of the requirement for the food to contain the stated amount of vitamin after normal storage, manufacturers commonly add more than the stated amount - so-called overage. One of the problems in the debate concerning folate enrichment of flour (Section 10.12) is the relatively small difference between the amount that is considered desirable and the amount that may pose a hazard to vulnerable population groups, and the precision to which manufacturers can control the amount in the final products. In pharmaceutical preparations, considerable latitude is allowed the U.S. Pharmacopeia permits preparations to contain from 90% to 150% of the declared amount of water-soluble vitamins and from 90% to 165% of the fat-soluble vitamins. 

A consequence of these studies is that the Food and Drug Administration (fTDA) has recomtnended that commercially available flour and cereal products be fortified w ith folic acid 1-4 tug folic acid/kg flour) for preventing NTDs (Tucker cf ai, 1996). The consumer interested in the folate level in any particular food can view the label on the package. Folic acid supplements have the effect of reducing the level of homocysteine in the blood. This homocysteine effect appears directly relevant to the prevention of atherosclerosis, but may also be relevant to neural tube defects. The reader interested in continuing developments regarding neural tube defects and folate should take note of the relationship between folate and homocysteine, presented in the Vitamin 8 section. 

Folic acid is easily lost during storage of fresh vegetables at room temperature and through many heat processes. Oxidative destruction of 50-95% of the folate can occur with protracted cooking or canning. Currently in the United States folate is added to all enriched or fortified cereal and flour products in order to increase this nutrient to prevent neural tube defects and to reduce coronary disease and some cancers. Thus, the processed, fortified product will have more folate. 

Manufacturing processes can result in a substantial loss of the vitamin for example, during the milling of whole wheat to white flour, 75% of the folate is lost (B8). Bread was found to contain more folate than the flour fixim which it was made and this was due to the effect of the added yeast. Folate deficiency has been found to be relatively uncommon in Iran and this prompted Russell (R8) to measure the folate content of various Iranian breads since bread is the staple food in that country. They found village wholemeal bread to have a free folate concentration of 340 M.g/kg and leavened breads made... 

Recent application of UPLC coupled with tand mass spectrometry (triple quadru-pole) has been reported for qnantitative analysis of folate in rice [41], fortified bread and flour [14,42]. These studies employed sub-2 pm particle columns, as they are specialized variants of the Cjg reversed phase that can bind polar organic compounds that still have some hydrophobic character. The aqneons mobile phase was 0.1% (v/v) formic acid in Milli-Q and the organic elnents were acetonitrile [14] and 0.1% formic acid in acetonitrile [41]. In both cases, the analytes were ionized and introduced into the MS using heated electrospray ionization (HESI). 

De Brouwer et al. (2010) identified 5 folate vitamers in their study 5-methyltet-rahydrofolate (the predominant vitamer), 5,10-methenyltetrahydrofolate and tetrahy-drofolate (the most labile vitamers), folic acid, and 10-formyl folic acid. This study reported that folate levels in wild-type rice were approximately 20 pg/lOO g lower than in bio-fortified rice [41], While separation of folate vitamers was obtained in 8 min run time, a previous LC-MS/MS method required 20 min [49]. Also, UPLC improved the sensitivity by reducing the limit of quantitation. Another study documented that endogenous 5-methyltetrahydrofolate in bread ranged between 1.3 and 3.4 pg/100 g [14]. Measurements of folic acid and 5-methyltetrahydrofolate in flour and infant milk formula have been successfully made using this method, described in the latter study. 

The introduction of 140 pg of folic acid per 100 g of flour in the USA, calculated to increase individual consumption of folic acid by 100 pgday , has reduced the incidence of abnormally low plasma folate from 21% to less than 2%, the incidence of mild hyperhomocysteinemia from 21% to 10%, and, most importantly, the incidence of NTD by about 20% over the first years of universal fortification. Because 30% of the population takes vitamin supplements and presumably would not be expected to derive significant benefit from fortification, the actual effect may be closer to a 30% decrease due to fortification. Recent calculations suggest that, for a variety of reasons, the overall fortification amount was about twice the mandatory amount. 

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