Food analysis water-soluble vitamins

WOJCIECHOWSKI C, DUPUY N, TA C D, HUVENNE J P and LEGRAND P (1998), Quantitative analysis of water-soluble vitamins by ATR-FTIR spectroscopy , Food Chem, 63, 133 10. woodward j r, brunsman A, gibson t D and Parker s (1998), Practical... 

This chapter does not constitute a comprehensive review of all recently published HPLC methods for the analysis of water-soluble vitamins. It is a summary of selected methods and is intended to serve as a tool for the analyst in search of a method for quantitating one or more of the water-soluble vitamins in foods. The selected methods must ... 

LF Russell. Water-soluble vitamins. In LML Nollet, ed. Handbook of Food Analysis, vol. 1. New York Marcel Dekker, 1996, pp 649-713. 

S Oties, Y Hisil. High pressure liquid chromatographic analysis of water soluble vitamins in eggs. Ital J Food Sci 5 69-73, 1993. 

The potential of PBI LC-MS in the analysis of various vitamins was explored by Careri et al. [99-100]. The fat-soluble vitamins A, D, and E were analysed in food and multivitamin preparations [99]. Absolute detection limits in SIM mode were 0.6-25 ng after fast leversed-phase separation using a 97% aqueous methanol as mobile phase. Mass spectra in El, positive-ion and negative-ion Cl were obtained and discussed. The mass-spectral and quantitative performance of PBI LC-MS in the analysis of eleven water-soluble vitamins was also explored [100]. Detection limits were determined in SIM mode under positive-ion Cl, and were below 15 ng for ascorbic acid, nicotinamide, nicotinic acid, and pyridoxal, around 100 ng for dehydroascorbic acid, panthothenic acid, and thiamine, and above 200 ng for biotin, pyridoxamime, and pyridoxine. Riboflavine was not detected. 

In general, the methods available for water-soluble vitamins are less successful for real samples than those described for the fat-soluble vitamins. The problems are, in general, related to sample preparation prior to LC analysis since naturally occurring vitamins are often bound to other food constituents such as carbohydrates or proteins. 

At present, much effort is being devoted to simultaneous separation and detection of water-soluble vitamins. Undoubtedly, multiple water-vitamin analysis using LC as a separation method is effective with RP ion pair chromatography with acidified methanol or acetonitrile water as the mobile phase. Detection is performed using combined systems such as UV absorbance and fluorescence systems, depending on the vitamins to be determined. Analysis in real food... 

Three methods of detection (UV absorbance, fluorescence, and electrochemical activity) are applicable for the analysis of water-soluble vitamins. Currently, UV absorption detection is used in many LC applications for water-soluble vitamins. A simultaneous assay of several vitamins with several wavelengths along with information of peak purity can be accomplished with a diode array absorbance detector. The detection limit of a UV detector is in the order of 1-10 ng (10-100 pmol), which is poorer than that of fluorescence and electrochemical detectors but often sufficient for analysis for many vitamins in foods and physiological samples (Table 4). The lack of selectivity of UV detection may cause problems with interfering and co-eluting contaminants especially in biological samples, thus necessitating sample purification prior to LC. 

DeLeenheer and Lambert (1996) updated the references to 1994 and extended the coverage in DeLeenheer et al. (1991) they reemphasized the importance of new developments in HPTLC-densitometry in modern studies on the analysis of lipophilic vitamins. Linnell (1996) stressed the importance of TLC analysis of water-soluble vitamins, particularly in pharmaceutical preparations and food products. He extended the earlier coverage by Fried (1991) and updated... 

Chromatographic analysis of the vitamin Bg complex, including sample preparation and pre-TLC extraction have been reviewed (14). Separation of pyridoxine from other water-soluble vitamins in pharmaceutical preparations may be facilitated by impregnating silica gel plates with zinc acetate to provide a self-indicating system after separation (7). Impregnation of plates with hexadecyltrimethyl-ammonium bromide has been used to improve the TLC analysis of vitamin in foods (9). Overpressure layer chromatography was found to provide better separation and resolution of B( from other compounds than HPTLC (11). 

ME using different CSPE-CNTs (SWCNTs and MWCNTs) to analyze a wide group of analytes of food significance, such as dietary antioxidants, water-soluble vitamins, vanilla flavors, and isofiavones involved in representative food samples, has been deeply studied [52]. Ultrafast separations at lowered oxidation potentials resulted in well defined and resolved peaks with enhanced voltammetric current when compared to those obtained from unmodified screen-printed electrodes thus making CNTs an ideal material for electrochemical sensing in food analysis. MWCNTs offered better performance as compared to SWCNTs. 

Water-soluble vitamins are formed by a wider group of compounds with different functions in humans. In fact, the number of water-soluble vitamins is higher than for the fat-soluble vitamins. The analysis of these compoimds by LC usually implies different extraction—sample treatment steps due to the possibility of finding these vitamins in foods bound to other components. In addition, the chemical nature of most water-soluble vitamins impairs their analysis because of the similarity with other components that may be coextracted and analyzed. 

MSFIA chromatographic analysis was also applied to food analysis (Fernandez et ak, 2012), including orange juice, strawberry milkshake, and malt, for simultaneous determination of six water-soluble vitamins (thiamine, riboflavin, ascorbic acid, nicotinic... 

Physicochemical methods are the most commonly employed and include the phases of extraction, purification, and final analysis. All these steps are critical in the vitamin evaluation. Extraction steps can include several treatments, such as heat, acid or alkali conditions, enzymes, and solvents, and these treatments have several purposes, such as vitamin stabilization and their release from other food components. Cleanup steps remove interfering compounds and are not necessary in many methods. Final determination and quantification can be mainly carried out by chromatographic [Table 8.1 summarizes some common high-performance liquid chromatography (HPLC) methods applied to water-soluble vitamin analysis], spectrometric, enzymatic, inmunological, or radiometric techniques. 

The latest volume. Methods of Analysis for Functional Foods and Nutraceuticals, second edition, edited by Dr. W. Jeffery Hurst (The Hershey Company Technical Center, Hershey, Pennsylvania) is organized into 10 chapters contributed by 22 leading scientists. This edition provides an updated, in-depth treatment of the peer-reviewed literature on methods of analysis for phytoestrogens, o)3 fatty acids, conjugated linoleic acid, flavonoids, anthocyanins, carotenoids, chlorophylls, water soluble vitamins, amino acids, and carbohydrates. 

Nutrient analysis of stabilized rice bran and its derivatives indicates that it is a good source of protein, dietary fiber and carbohydrates, in addition to several valuable phytonutrients, antioxidants, vitamins and minerals (Table 17.1). SRB and its water-soluble and water-insoluble derivatives contain all the nutrients at different levels. They are gluten and lactose free and do not give rise to any food allergy. 

See also Amperometry. Derivatization of Anaiytes. Food and Nutritional Analysis Meat and Meat Products Dairy Products. Liquid Chromatography Food Applications. Nitrogen. Polarography Inorganic Applications. Quality Assurance Primary Standards. Spectrophotometry Organic Compounds. Sulfur. Vitamins Fat-Soluble Water-Soluble. 

Inductively Coupled Plasma. Carbohydrates Sugars -Spectrophotometric Methods Starch. Food and Nutritional Analysis Oven/iew Antioxidants and Presen/atives Oils and Fats. Ion-Selective Electrodes Food Applications. Liquid Chromatography Amino Acids. Proteins Foods. Quality Assurance Quality Control. Sampling Theory. Vitamins Fat-Soluble Water-Soluble. Water Determination. 

See also Carbohydrates Overview. Extraction Solid-Phase Extraction Supercritical Fluid Extraction. Food and Nutritional Analysis Sample Preparation Antioxidants and Preservatives Mycotoxins Oils and Fats. Lip-Ids Overview. Peptides. Proteins Overview. Toxins Mycotoxins Neurotoxins. Vitamins Overview Fat-Soluble Water-Soluble. 

Niemeijer, R., Haas-Lauterbach, S., Stengi, S., and Weber, W., 2009. Determination of water-soluble B-vitamins with VitaFast tests in fruits and fruit products. In Proceedings of 4th International Symposium on Recent Advances in Food Analysis. November 4-6, 2009, Prague, Czech Republic, p. 566. 

Reversed-phase chromatography is the most popular mode for the separation of low molecular weight (<3000), neutral species that are soluble in water or other polar solvents. It is widely used in the pharmaceutical industry for separation of species such as steroids, vitamins, and /3-blockers. It is also used in other areas for example, in clinical laboratories for analysis of catecholamines, in the chemical industry for analysis of polymer additives, in the environmental arena for analysis of pesticides and herbicides, and in the food and beverage industry for analysis of carbohydrates, sweeteners, and food additives. 

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