Food analysis folates

The book covers food analysis for beneficial compounds, such as the determination of folate, vitamin content analysis, applications for avocado metabolite studies, virgin olive oil component analysis, lactose determination in milk, and analysis of minor components of cocoa and phenolic compounds in fruits and vegetables. With contributions by experts in interdisciplinary fields, this reference offers practical information for readers in research and development, production, and routing analysis of foods and food products. 

Finglas, P.M., Faulks, R.M., and Morgan, M.R.A., 1988. The development and characterization of a protein-binding assay for the determination of folate—potential use in food analysis. Journal of Micronutrient Analysis. 4 295-308. 

CK Clifford, AJ Clifford. High pressure liquid chromatographic analysis of food for folates. J Assoc Off Anal Chem 60 1248-1251, 1977. 

The major sources of folate are green vegetables, citrus fruits, legumes, egg yolk, wheat germ, and yeast [417]. This vitamin can be added only in the form of pteroylmonoglutamic acid [402]. The multiplicity of forms, low stability, low concentration, and the complex extraction and detection techniques make the analysis of folate in food a difficult task. 

CA Martin. Folate analysis in foods. How accurate is it BNF Nutr Bull 20 8-15, 1995. 

L Vahteristo, PM Finglas, C Witthoft, K Wigertz, R Seale, I de Froidmont-Gortz. Third EU MAT intercomparison study on food folate analysis using HPLC procedures. Food Chem 57 109-111,1996. 

E Seyoum, J Selhub. Combined affinity and ion pair column chromatographies for the analysis of food folate. J Nutr Biochem 4 488-494, 1993. 

LT Vahteristo, V Ollilainen, PE Koivistoinen, P Varo. Improvements in the analysis of reduced folate monoglutamates and folic acid in food by high-performance liquid chromatography. J Agric Food Chem 44 477-482, 1996. 

Folates are generally present in low concentration in foods thus, any method of analysis requires isolation and sensitive detection (Vahteristo et. al., 1996). The method described here uses extraction of the folic acid (Fig. 9.13) with rapid microwave heating and enzymatic deconjugation with hog-kidney con-jugase and chicken pancreatic enzymes. The extracts are purified with strong anion-exchange SPE. The final analysis is with HPLC. 

As an alternative to the long-term controlled dietary protocol, a similar study was conducted with free-living men n = 4) consuming self-selected diets (Stites et oL, 1994). After a 2-week equilibration period with 200 /xg/ day unlabeled folate supplement, the subjects consumed 200 jttg/day of a 1 1 mixture of d4-folic acid and unlabeled folic add for an 8-week period, followed by a switch back to 200 /ig/day of unlabeled folate. Dietary folate intake was estimated from food records using a computerized data base. Typical results (Fig. 7) indicate slow labeling of body folate, as discussed above. Analysis of these data using the expanded model (Fig. 6) yielded... 

Dietary folate intake determines folate nutritional status. It is therefore important to accurately measure folate in food using the best analytical platform currently available. In particular, folate analysis is confounded by several factors, such as the presence of many vitamers, low concentrations, physicochemical instability, and complex sample preparation [12]. It has been reported that the levels of endogenous 5-methyltetrahydrofolate and 5-formyltetrahydrofolate in canned chickpeas, a rich folate source, were 52 and 8 pg/lOO g, respectively [13]. Folate-fortified foods contain higher total folate concentrations than those found in natural folate-rich foods. We recently determined folic acid in Australian fortified bread varieties that was approximately 100 [tg/100 g [14]. 

Ringling, C. and Rychlik, M. 2013. Analysis of seven folates in food by LC-MS/MS to improve accuracy of total folate data. Eur. Food Res. Technol. 236 17-28. 

Chandra-Hioe, M. V., Bucknall, M. R, and Arcot, J. 2011. Folate analysis in foods by UPLC-MS/MS Development and validation of a novel, high throughput quantitative assay folate levels determined in Australian fortified breads. Anal. Bioanal Chem. 401 1035-1042. 

Vishnumohan, S., Arcot, J., andPickford, R. 2011. Naturally-occurring folates in foods Method development and analysis using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Food Chem. 125 736-742. 

Hyun, T. H. and Tamura, T. 2005. Trienzyme extraction in combination with micro-biologic assay in food folate analysis An updated review. Experimental Biology and Medicine. 230 444-454. 

To ascertain whether dietary food records were inaccurate because of associated mild cognitive deficits, blood levels of these nutrients were measured. Scores on the Halstead-Reitan Category Test were worse in subjects with lower blood levels of ascorbate, riboflavin, Bj2, and folate, while those on the Wexler Memory Test were correlated with ascorbate and Bj2 levels. These findings do not appear to be explained by age variation within the group, since there was no overall correlation between any nutritional variable and age per se. To correct for any effects of educational status and income level, analysis of covariance was performed it did not alter the degree or the statistical significance of the associations between performance on the cognitive tests and blood levels of the vitamins. 

The multiplicity of forms of folate, their low stability and low levels in blood or foods make quantitative analysis of folate difficult. Different methods are available for measuring the status of folate in the population and in clinical... 

Different methods are available for folate status measurement and for folate analysis in foods. 

Arcot, J., and Shrestha, A.K., 2005. Folates methods of analysis in foods. Trends in Food Science ctnd Technology. 16 253-266. 

Rychlik, M., Englert, K., Kapfer, S., and Kirchhoff, E., 2007. Folate contents of legumes determined by optimized enzyme treatment and stable isotope dilution assays. Journal of Food Composition and Analysis. 20 411-419. 

In an analysis of data from the Mother and Child Cohort study in Norway, where foods are not fortified, wheezing and lower respiratory tract infections during the first 18 months of life were examined in 32 077 children born between 2000 and 2005 in relation to maternal reported intake of folic acid 400 mg/day and cod liver oil 5 ml/day [29 , 30" ]. The relative risks in the infants of mothers who took folate supplements during the first trimester were 1.06 (95% Cl = 1.03, 1.10) for wheezing, 1.09 (95% Cl = 1.02, 1.15) for lower respiratory tract infections, and 1.24 (95% Cl = 1.09, 1.41) for hospitalization associated with lower respiratory tract infections. Although small, these relative risks were statistically significant. 

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