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Paul W. Johns - One of the best experts on this subject based on the ideXlab platform.
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Verification of 5-Methyltetrahydrofolic Acid in Nutritional Products
Food Analytical Methods, 2017Co-Authors: Paul W. Johns, Jeffrey H. Baxter, Megan C. TerpAbstract:A simple method for the verification of supplemental (6R,S)-5-methyl-5,6,7,8-tetrahydrofolic acid, “5-MTHF,” in Nutritional Products is described. Nutritional Product samples are prepared for the liquid chromatographic/fluorescence detection (LC/FLD) determination of 5-MTHF by buffer dilution, 10-min centrifugation, and syringe filtration. Method performance has been defined by assessments of 5-MTHF linearity ( r ^2 averaged 0.9999 ± 0.0001, and all relative calibration errors averaged ≤0.6%, for ten consecutive six-point standard curves), intermediate precision (rsd = 1.1%, n = 9, for three Products fortified at ∼1.73 μmol/kg = ∼795 μg/kg, tested on each of 3 days), accuracy (spike recovery average = 92.8 ± 1.0%, n = 9, for Nutritional Products spiked with 5-MTHF at ∼1.73 μmol/kg, or ∼795 μg/kg), and selectivity (absence of interference from reagent blanks, and from four compounds structurally related to 5-MTHF). The 5-MTHF recovery, as % of unheated controls, from a simulated heat treatment (20 min at 120 °C) averaged 99.1 ± 0.6%, n = 4. The limits of 5-MTHF detection (S/ N = 3) and quantification (S/ N = 10) were experimentally determined to be 10 μg/kg (∼0.020 μmol/kg) and 30 μg/kg (∼0.060 μmol/kg), respectively (
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Characterisation of peptide molecular mass distribution in commercial hydrolysates and hydrolysate-based Nutritional Products
Food Chemistry, 2011Co-Authors: Paul W. Johns, Wesley A. Jacobs, Rosalyn R. Phillips, Ronald J. Mckenna, Kimberly A. O’kane, John W. McewenAbstract:Abstract High performance size exclusion chromatography with UV detection (HPSEC/UV) was evaluated for the routine characterisation of peptide molecular mass distributions in commercial protein hydrolysates and in protein hydrolysate-based liquid Nutritional Products. Several known sources of quantitative error were examined, as were additional sources potentially introduced by the complex matrices of liquid Nutritional Products. Although it is clear that these sources may compromise the accuracy of the molecular mass distribution estimates, the magnitude was typically small, and did not detract appreciably from method applicability. Method capability for reliably discriminating different lots of the same hydrolysate commodity was established via median molecular mass determinations. The molecular mass profiles of liquid Nutritional Products (median molecular mass range = 300–3610 Da) agreed well with those of their protein hydrolysate ingredient: the median molecular mass ratios for Nutritional Product to hydrolysate ingredient averaged 0.984 ± 0.091 ( n = 5). The study demonstrated the considerable utility of the HPSEC/UV method as a direct, informative, simple, precise, rugged, and relatively inexpensive means for the routine characterisation of peptide molecular mass distributions in commercial protein hydrolysates and in hydrolysate-based liquid Nutritional Products.
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Characterisation of peptide molecular mass distribution in commercial hydrolysates and hydrolysate-based Nutritional Products
Food Chemistry, 2011Co-Authors: Paul W. Johns, Wesley A. Jacobs, Rosalyn R. Phillips, Ronald J. Mckenna, Kimberly A. O’kane, John W. McewenAbstract:Abstract High performance size exclusion chromatography with UV detection (HPSEC/UV) was evaluated for the routine characterisation of peptide molecular mass distributions in commercial protein hydrolysates and in protein hydrolysate-based liquid Nutritional Products. Several known sources of quantitative error were examined, as were additional sources potentially introduced by the complex matrices of liquid Nutritional Products. Although it is clear that these sources may compromise the accuracy of the molecular mass distribution estimates, the magnitude was typically small, and did not detract appreciably from method applicability. Method capability for reliably discriminating different lots of the same hydrolysate commodity was established via median molecular mass determinations. The molecular mass profiles of liquid Nutritional Products (median molecular mass range = 300–3610 Da) agreed well with those of their protein hydrolysate ingredient: the median molecular mass ratios for Nutritional Product to hydrolysate ingredient averaged 0.984 ± 0.091 ( n = 5). The study demonstrated the considerable utility of the HPSEC/UV method as a direct, informative, simple, precise, rugged, and relatively inexpensive means for the routine characterisation of peptide molecular mass distributions in commercial protein hydrolysates and in hydrolysate-based liquid Nutritional Products.
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Effect of carbohydrate DE on blocked lysine and furosine in a liquid Nutritional Product
Food Chemistry, 2010Co-Authors: John W. Mcewen, Kimberly A. O’kane, Rosalyn R. Phillips, Ronald Mckenna, Paul W. JohnsAbstract:Abstract A controlled, quantitative study of Maillard browning vs. dextrose equivalents (DE) was performed on a liquid Nutritional Product. The early stage Maillard markers furosine and available lysine were determined in retort-sterilised, pilot scale batches formulated with carbohydrate systems with DE variations of 2, 4, 10, and 20. Both markers varied proportionately with DE; every DE increase of 2 units resulted in the blockage (glycation) of an additional 1% of total lysine. When DE 20 maltodextrin was replaced with an 80/20 blend of DE 5 maltodextrin and sucrose (blend DE = 4), lysine blockage decreased by 831 mg/100 g protein, which was 8.25% of the total lysine, and the mole equivalent of 1.75 g of fructoselysine. The quantitative browning/DE relationships enable reliable projections of the Nutritional benefits which may be attained through the use of low-DE maltodextrins.
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Evaluations of protein-metal association in Nutritional Products
International Dairy Journal, 1Co-Authors: Paul W. Johns, Ronald Mckenna, Deborah Strozier, Jonny Veldhuis, Luke E. Weber, Joseph J ThompsonAbstract:Abstract Protein-metal association may occur in Nutritional Products, with consequences for organoleptic quality, nutrient stability, and metal bioavailability. Insights into protein-metal associations were obtained by “centrifugation analysis”: high speed centrifugation followed by determinations of protein and minerals in the serum (supernatant). Experimental data suggested that the distribution of iron in a dairy-based Nutritional Product emulsion could be modified by milk protein ingredient selection. Each serum mineral concentration (Ca, Cu, Fe, Mg, Mn, P, and Zn) was correlated with serum protein (R2 = 0.95 to 0.99), and the association of a divalent metal with serum protein was correlated with its fortification rate. Iron and/or zinc association with serum protein increased with cysteine and/or native whey protein increases in Nutritional Products. Flavoring and/or coloring ingredients could alter serum mineral concentration. Strong correlations in the experimental data provide information upon which strategies could be formed for improving dairy-based Nutritional Product quality, stability, and performance.
John W. Mcewen - One of the best experts on this subject based on the ideXlab platform.
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Characterisation of peptide molecular mass distribution in commercial hydrolysates and hydrolysate-based Nutritional Products
Food Chemistry, 2011Co-Authors: Paul W. Johns, Wesley A. Jacobs, Rosalyn R. Phillips, Ronald J. Mckenna, Kimberly A. O’kane, John W. McewenAbstract:Abstract High performance size exclusion chromatography with UV detection (HPSEC/UV) was evaluated for the routine characterisation of peptide molecular mass distributions in commercial protein hydrolysates and in protein hydrolysate-based liquid Nutritional Products. Several known sources of quantitative error were examined, as were additional sources potentially introduced by the complex matrices of liquid Nutritional Products. Although it is clear that these sources may compromise the accuracy of the molecular mass distribution estimates, the magnitude was typically small, and did not detract appreciably from method applicability. Method capability for reliably discriminating different lots of the same hydrolysate commodity was established via median molecular mass determinations. The molecular mass profiles of liquid Nutritional Products (median molecular mass range = 300–3610 Da) agreed well with those of their protein hydrolysate ingredient: the median molecular mass ratios for Nutritional Product to hydrolysate ingredient averaged 0.984 ± 0.091 ( n = 5). The study demonstrated the considerable utility of the HPSEC/UV method as a direct, informative, simple, precise, rugged, and relatively inexpensive means for the routine characterisation of peptide molecular mass distributions in commercial protein hydrolysates and in hydrolysate-based liquid Nutritional Products.
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Characterisation of peptide molecular mass distribution in commercial hydrolysates and hydrolysate-based Nutritional Products
Food Chemistry, 2011Co-Authors: Paul W. Johns, Wesley A. Jacobs, Rosalyn R. Phillips, Ronald J. Mckenna, Kimberly A. O’kane, John W. McewenAbstract:Abstract High performance size exclusion chromatography with UV detection (HPSEC/UV) was evaluated for the routine characterisation of peptide molecular mass distributions in commercial protein hydrolysates and in protein hydrolysate-based liquid Nutritional Products. Several known sources of quantitative error were examined, as were additional sources potentially introduced by the complex matrices of liquid Nutritional Products. Although it is clear that these sources may compromise the accuracy of the molecular mass distribution estimates, the magnitude was typically small, and did not detract appreciably from method applicability. Method capability for reliably discriminating different lots of the same hydrolysate commodity was established via median molecular mass determinations. The molecular mass profiles of liquid Nutritional Products (median molecular mass range = 300–3610 Da) agreed well with those of their protein hydrolysate ingredient: the median molecular mass ratios for Nutritional Product to hydrolysate ingredient averaged 0.984 ± 0.091 ( n = 5). The study demonstrated the considerable utility of the HPSEC/UV method as a direct, informative, simple, precise, rugged, and relatively inexpensive means for the routine characterisation of peptide molecular mass distributions in commercial protein hydrolysates and in hydrolysate-based liquid Nutritional Products.
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Effect of carbohydrate DE on blocked lysine and furosine in a liquid Nutritional Product
Food Chemistry, 2010Co-Authors: John W. Mcewen, Kimberly A. O’kane, Rosalyn R. Phillips, Ronald Mckenna, Paul W. JohnsAbstract:Abstract A controlled, quantitative study of Maillard browning vs. dextrose equivalents (DE) was performed on a liquid Nutritional Product. The early stage Maillard markers furosine and available lysine were determined in retort-sterilised, pilot scale batches formulated with carbohydrate systems with DE variations of 2, 4, 10, and 20. Both markers varied proportionately with DE; every DE increase of 2 units resulted in the blockage (glycation) of an additional 1% of total lysine. When DE 20 maltodextrin was replaced with an 80/20 blend of DE 5 maltodextrin and sucrose (blend DE = 4), lysine blockage decreased by 831 mg/100 g protein, which was 8.25% of the total lysine, and the mole equivalent of 1.75 g of fructoselysine. The quantitative browning/DE relationships enable reliable projections of the Nutritional benefits which may be attained through the use of low-DE maltodextrins.
Rosalyn R. Phillips - One of the best experts on this subject based on the ideXlab platform.
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Characterisation of peptide molecular mass distribution in commercial hydrolysates and hydrolysate-based Nutritional Products
Food Chemistry, 2011Co-Authors: Paul W. Johns, Wesley A. Jacobs, Rosalyn R. Phillips, Ronald J. Mckenna, Kimberly A. O’kane, John W. McewenAbstract:Abstract High performance size exclusion chromatography with UV detection (HPSEC/UV) was evaluated for the routine characterisation of peptide molecular mass distributions in commercial protein hydrolysates and in protein hydrolysate-based liquid Nutritional Products. Several known sources of quantitative error were examined, as were additional sources potentially introduced by the complex matrices of liquid Nutritional Products. Although it is clear that these sources may compromise the accuracy of the molecular mass distribution estimates, the magnitude was typically small, and did not detract appreciably from method applicability. Method capability for reliably discriminating different lots of the same hydrolysate commodity was established via median molecular mass determinations. The molecular mass profiles of liquid Nutritional Products (median molecular mass range = 300–3610 Da) agreed well with those of their protein hydrolysate ingredient: the median molecular mass ratios for Nutritional Product to hydrolysate ingredient averaged 0.984 ± 0.091 ( n = 5). The study demonstrated the considerable utility of the HPSEC/UV method as a direct, informative, simple, precise, rugged, and relatively inexpensive means for the routine characterisation of peptide molecular mass distributions in commercial protein hydrolysates and in hydrolysate-based liquid Nutritional Products.
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Characterisation of peptide molecular mass distribution in commercial hydrolysates and hydrolysate-based Nutritional Products
Food Chemistry, 2011Co-Authors: Paul W. Johns, Wesley A. Jacobs, Rosalyn R. Phillips, Ronald J. Mckenna, Kimberly A. O’kane, John W. McewenAbstract:Abstract High performance size exclusion chromatography with UV detection (HPSEC/UV) was evaluated for the routine characterisation of peptide molecular mass distributions in commercial protein hydrolysates and in protein hydrolysate-based liquid Nutritional Products. Several known sources of quantitative error were examined, as were additional sources potentially introduced by the complex matrices of liquid Nutritional Products. Although it is clear that these sources may compromise the accuracy of the molecular mass distribution estimates, the magnitude was typically small, and did not detract appreciably from method applicability. Method capability for reliably discriminating different lots of the same hydrolysate commodity was established via median molecular mass determinations. The molecular mass profiles of liquid Nutritional Products (median molecular mass range = 300–3610 Da) agreed well with those of their protein hydrolysate ingredient: the median molecular mass ratios for Nutritional Product to hydrolysate ingredient averaged 0.984 ± 0.091 ( n = 5). The study demonstrated the considerable utility of the HPSEC/UV method as a direct, informative, simple, precise, rugged, and relatively inexpensive means for the routine characterisation of peptide molecular mass distributions in commercial protein hydrolysates and in hydrolysate-based liquid Nutritional Products.
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Effect of carbohydrate DE on blocked lysine and furosine in a liquid Nutritional Product
Food Chemistry, 2010Co-Authors: John W. Mcewen, Kimberly A. O’kane, Rosalyn R. Phillips, Ronald Mckenna, Paul W. JohnsAbstract:Abstract A controlled, quantitative study of Maillard browning vs. dextrose equivalents (DE) was performed on a liquid Nutritional Product. The early stage Maillard markers furosine and available lysine were determined in retort-sterilised, pilot scale batches formulated with carbohydrate systems with DE variations of 2, 4, 10, and 20. Both markers varied proportionately with DE; every DE increase of 2 units resulted in the blockage (glycation) of an additional 1% of total lysine. When DE 20 maltodextrin was replaced with an 80/20 blend of DE 5 maltodextrin and sucrose (blend DE = 4), lysine blockage decreased by 831 mg/100 g protein, which was 8.25% of the total lysine, and the mole equivalent of 1.75 g of fructoselysine. The quantitative browning/DE relationships enable reliable projections of the Nutritional benefits which may be attained through the use of low-DE maltodextrins.
Kimberly A. O’kane - One of the best experts on this subject based on the ideXlab platform.
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Characterisation of peptide molecular mass distribution in commercial hydrolysates and hydrolysate-based Nutritional Products
Food Chemistry, 2011Co-Authors: Paul W. Johns, Wesley A. Jacobs, Rosalyn R. Phillips, Ronald J. Mckenna, Kimberly A. O’kane, John W. McewenAbstract:Abstract High performance size exclusion chromatography with UV detection (HPSEC/UV) was evaluated for the routine characterisation of peptide molecular mass distributions in commercial protein hydrolysates and in protein hydrolysate-based liquid Nutritional Products. Several known sources of quantitative error were examined, as were additional sources potentially introduced by the complex matrices of liquid Nutritional Products. Although it is clear that these sources may compromise the accuracy of the molecular mass distribution estimates, the magnitude was typically small, and did not detract appreciably from method applicability. Method capability for reliably discriminating different lots of the same hydrolysate commodity was established via median molecular mass determinations. The molecular mass profiles of liquid Nutritional Products (median molecular mass range = 300–3610 Da) agreed well with those of their protein hydrolysate ingredient: the median molecular mass ratios for Nutritional Product to hydrolysate ingredient averaged 0.984 ± 0.091 ( n = 5). The study demonstrated the considerable utility of the HPSEC/UV method as a direct, informative, simple, precise, rugged, and relatively inexpensive means for the routine characterisation of peptide molecular mass distributions in commercial protein hydrolysates and in hydrolysate-based liquid Nutritional Products.
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Characterisation of peptide molecular mass distribution in commercial hydrolysates and hydrolysate-based Nutritional Products
Food Chemistry, 2011Co-Authors: Paul W. Johns, Wesley A. Jacobs, Rosalyn R. Phillips, Ronald J. Mckenna, Kimberly A. O’kane, John W. McewenAbstract:Abstract High performance size exclusion chromatography with UV detection (HPSEC/UV) was evaluated for the routine characterisation of peptide molecular mass distributions in commercial protein hydrolysates and in protein hydrolysate-based liquid Nutritional Products. Several known sources of quantitative error were examined, as were additional sources potentially introduced by the complex matrices of liquid Nutritional Products. Although it is clear that these sources may compromise the accuracy of the molecular mass distribution estimates, the magnitude was typically small, and did not detract appreciably from method applicability. Method capability for reliably discriminating different lots of the same hydrolysate commodity was established via median molecular mass determinations. The molecular mass profiles of liquid Nutritional Products (median molecular mass range = 300–3610 Da) agreed well with those of their protein hydrolysate ingredient: the median molecular mass ratios for Nutritional Product to hydrolysate ingredient averaged 0.984 ± 0.091 ( n = 5). The study demonstrated the considerable utility of the HPSEC/UV method as a direct, informative, simple, precise, rugged, and relatively inexpensive means for the routine characterisation of peptide molecular mass distributions in commercial protein hydrolysates and in hydrolysate-based liquid Nutritional Products.
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Effect of carbohydrate DE on blocked lysine and furosine in a liquid Nutritional Product
Food Chemistry, 2010Co-Authors: John W. Mcewen, Kimberly A. O’kane, Rosalyn R. Phillips, Ronald Mckenna, Paul W. JohnsAbstract:Abstract A controlled, quantitative study of Maillard browning vs. dextrose equivalents (DE) was performed on a liquid Nutritional Product. The early stage Maillard markers furosine and available lysine were determined in retort-sterilised, pilot scale batches formulated with carbohydrate systems with DE variations of 2, 4, 10, and 20. Both markers varied proportionately with DE; every DE increase of 2 units resulted in the blockage (glycation) of an additional 1% of total lysine. When DE 20 maltodextrin was replaced with an 80/20 blend of DE 5 maltodextrin and sucrose (blend DE = 4), lysine blockage decreased by 831 mg/100 g protein, which was 8.25% of the total lysine, and the mole equivalent of 1.75 g of fructoselysine. The quantitative browning/DE relationships enable reliable projections of the Nutritional benefits which may be attained through the use of low-DE maltodextrins.
Wesley A. Jacobs - One of the best experts on this subject based on the ideXlab platform.
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Characterisation of peptide molecular mass distribution in commercial hydrolysates and hydrolysate-based Nutritional Products
Food Chemistry, 2011Co-Authors: Paul W. Johns, Wesley A. Jacobs, Rosalyn R. Phillips, Ronald J. Mckenna, Kimberly A. O’kane, John W. McewenAbstract:Abstract High performance size exclusion chromatography with UV detection (HPSEC/UV) was evaluated for the routine characterisation of peptide molecular mass distributions in commercial protein hydrolysates and in protein hydrolysate-based liquid Nutritional Products. Several known sources of quantitative error were examined, as were additional sources potentially introduced by the complex matrices of liquid Nutritional Products. Although it is clear that these sources may compromise the accuracy of the molecular mass distribution estimates, the magnitude was typically small, and did not detract appreciably from method applicability. Method capability for reliably discriminating different lots of the same hydrolysate commodity was established via median molecular mass determinations. The molecular mass profiles of liquid Nutritional Products (median molecular mass range = 300–3610 Da) agreed well with those of their protein hydrolysate ingredient: the median molecular mass ratios for Nutritional Product to hydrolysate ingredient averaged 0.984 ± 0.091 ( n = 5). The study demonstrated the considerable utility of the HPSEC/UV method as a direct, informative, simple, precise, rugged, and relatively inexpensive means for the routine characterisation of peptide molecular mass distributions in commercial protein hydrolysates and in hydrolysate-based liquid Nutritional Products.
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Characterisation of peptide molecular mass distribution in commercial hydrolysates and hydrolysate-based Nutritional Products
Food Chemistry, 2011Co-Authors: Paul W. Johns, Wesley A. Jacobs, Rosalyn R. Phillips, Ronald J. Mckenna, Kimberly A. O’kane, John W. McewenAbstract:Abstract High performance size exclusion chromatography with UV detection (HPSEC/UV) was evaluated for the routine characterisation of peptide molecular mass distributions in commercial protein hydrolysates and in protein hydrolysate-based liquid Nutritional Products. Several known sources of quantitative error were examined, as were additional sources potentially introduced by the complex matrices of liquid Nutritional Products. Although it is clear that these sources may compromise the accuracy of the molecular mass distribution estimates, the magnitude was typically small, and did not detract appreciably from method applicability. Method capability for reliably discriminating different lots of the same hydrolysate commodity was established via median molecular mass determinations. The molecular mass profiles of liquid Nutritional Products (median molecular mass range = 300–3610 Da) agreed well with those of their protein hydrolysate ingredient: the median molecular mass ratios for Nutritional Product to hydrolysate ingredient averaged 0.984 ± 0.091 ( n = 5). The study demonstrated the considerable utility of the HPSEC/UV method as a direct, informative, simple, precise, rugged, and relatively inexpensive means for the routine characterisation of peptide molecular mass distributions in commercial protein hydrolysates and in hydrolysate-based liquid Nutritional Products.