Food fortification folates

Folate is the generic name used to refer to a family of vitamers with related biological activity. Instead, folic acid (pteroylglutamin acid, PGA) (Fignre 19.16) refers to the most oxidized, stable, and easily adsorbable synthetic form (monoglutamate). It is commonly nsed in food supplements and in food fortification because of its stability and becomes biologically active after redaction. 

CIO. Colman, N., Larsen, J. V., Barker, M., Barker, E. A., Green, R., and Metz, J., Prevention of folate deficiency by food fortification. V. A pilot field trial of folic acid-fortified maize meal. S. Afr. Med. J. 48, 1763-1766 (1974). 

Nevertheless, despite the decline of cardiovascular risk in North America after the introduction of folate food fortification (Yang et al. 2006), large clinical trials in patients with coronary heart disease (CHD) failed to demonstrate any benefit from B vitamins administration (Clarke et al. 2010). Despite... 

However large RCTs, such as VISP (Toole et al. 2004) or VITATOPS (Anonymous 2010) have failed to document any significant effects of B vitamins on stroke prevention. Post hoc analyses, such as that of HOPE-2 (Saposnik et al. 2009) have suggested that folate, Bg and B12 could reduce stroke risk in patients with known CVD, mainly if patients were younger than 70 years, recruited from regions without folic acid food fortification, with higher baseline cholesterol and Hey levels, and not under antiplatelet or lipid-lowering... 

Concerns have been raised on possible risks that food fortification with folate carries. 

Hoey, L., McNulty, H., Askin, N., Dunne, A., Ward, M., Pentieva, K., Strain, J., Molloy, A.M., Flynn, C.A., and Scott, J.M., 2007. Effect of a voluntary food fortification policy on folate, related B vitamin status, and homocysteine in healthy adults. The American Journal of Clinical Nutrition. 86 1405-1413. 

Tumours The association between intakes of folate, vitamin Bs and vitamin B12 and the risk of colorectal cancer in women has been examined. Food fortification with folic acid for 3-9 years was associated with an increased risk... 

On balance, the introduction of food fortification with folate is regarded as beneficial not only in preventing NTD but also in reducing the incidences... 

EA Yetley, JI Rader. Folate fortification of cereal-grain products FDA policies and actions. Cereal Foods World 40 67-70, 72, 1995. 

Based on folate concentrations in liver biopsy samples, and assuming that the liver contains about half of ail body stores, total body stores of folate are estimated to be between 12 and 28 Kinetic studies that show both fast-turnover and very-slow-turnover folate pools indicate that about 0.5% to 1% of body stores are catabolized or excreted daily,suggesting a minimum daily requirement of between 60 and 280)Llg to replace losses. In calculating nutritional requirement, the concept of dietary folate equivalents (DFE) has been used to adjust for the nearly 50% lower bioavailabihty of food folate compared with supplemental folic acid, such that 1 p.g DFE = 0.6 Llg of folic acid from fortified food = 1 j,g of food folate 0.5 p.g foUc acid supplement taken on an empty stomach. Before the fortification program of cereal grains with folic acid conducted between 1988 and 1994, the median intake of folate from food in the United States was approximately 250p.g/day this figure is expected to increase by about 100 Llg/day after fortification. Recommendations... 

However, a dispute about folate fortification arouse in the last years as the decreasing trend of colon cancer inverted in some countries with mandatory folate fortification since its implementation (Mason et al. 2007). Therefore, many countries in the EU refuse mandatory fortification and favour the consumption of foods endogenously high in folates or increasing folate content in foods, generally. 

Table 25.2 Applications of stable isotope dilution assays (SIDAs) to food folates. Reported SID As for foods with and without fortification with folic acid are listed along with the isotopologic standard used.

Applications of folate stable isotope dilution assays are reported for foods with or without fortification by folic acid and for clinical samples such as blood serum, plasma, red blood cells, urine and ileostomy effluents. 

Reference Intakes for folate have been reported (Food and Nutrition Board 1998) (Table 44.2). The high frequency of folate deficiency has led the Food and Drug Administration in the United States to require folic acid fortification of all enriched cereals and grain products since January 1998. Folate deficiency is a major public health concern both northern and southern countries, and affects both industrialized and non-industrialized nations. In non-industrialized countries, it is particularly accentuated by poverty, limited access to food resources, and infectious diseases (Change and Abdennebi-Najar, 2011). 

Gregory, J.F., Quinlivan, E.R, Davis, S.R. Integrating the issues of folate bioavailability, intake and metabolism in the era of fortification. Trends Food Sci. Technol. 16, 229 (2005)... 

JI Rader, CM Weaver, G Angyal. Use of microbiological assay with tri-enzyme extraction for measurement of pre-fortification levels of folates in enriched cereal-grain products. Food Chem 62 451 65, 1998. 

A detailed description of microbial synthesis of the three most relevant B-group vitamins (riboflavin, folate, and cobalamin) by LAB has been discussed in detail previously (LeBlanc et al. 2010a) and will not be the focus of this chapter. Here, the most recent applications of beneficial microorganisms in order to increase the concentration of vitamins through microbial biosynthesis will be discussed as an economically attractive alternative to mandatory fortification of foods. 

Milk is not a rich source of dietary folate compared to other foods however, as is the case for riboflavin, folate concentrations can be significantly increased in many dairy products due to microbial fermentation. Among dairy products, fermented milks are considered a good potential matrix for folate fortification because folate-binding proteins present in milk improve folate stability and enhance the bioavailability of both 5-methyltetrahydrofolate (the most predominant natural form of the vitamin) and folic acid (Jones and Nixon 2002 Aryana 2003 Verwei et al. 2003). However, due to the potential risks of fortification with folic acid, the elaboration of fermented milks containing elevated levels of natural folates would be a better suited alternative. 

Gangadharan, D. and Nampoothiri, K.M. (2011) Folate production using Lactococcus lactis ssp cremoris with implications for fortification of skim milk and fruit juices. LWT - Food Sci Technol 44,1859-1864. 

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