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1.
Microb Cell Fact ; 21(1): 48, 2022 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-35346203

RESUMEN

BACKGROUND: Sunflower seeds (Helianthus annuus) display an attractive source for the rapidly increasing market of plant-based human nutrition. Of particular interest are press cakes of the seeds, cheap residuals from sunflower oil manufacturing that offer attractive sustainability and economic benefits. Admittedly, sunflower seed milk, derived therefrom, suffers from limited nutritional value, undesired flavor, and the presence of indigestible sugars. Of specific relevance is the absence of vitamin B12. This vitamin is required for development and function of the central nervous system, healthy red blood cell formation, and DNA synthesis, and displays the most important micronutrient for vegans to be aware of. Here we evaluated the power of microbes to enrich sunflower seed milk nutritionally as well as in flavor. RESULTS: Propionibacterium freudenreichii NCC 1177 showed highest vitamin B12 production in sunflower seed milk out of a range of food-grade propionibacteria. Its growth and B12 production capacity, however, were limited by a lack of accessible carbon sources and stimulants of B12 biosynthesis in the plant milk. This was overcome by co-cultivation with Bacillus amyloliquefaciens NCC 156, which supplied lactate, amino acids, and vitamin B7 for growth of NCC 1177 plus vitamins B2 and B3, potentially supporting vitamin B12 production by the Propionibacterium. After several rounds of optimization, co-fermentation of ultra-high-temperature pre-treated sunflower seed milk by the two microbes, enabled the production of 17 µg (100 g)-1 vitamin B12 within four days without any further supplementation. The fermented milk further revealed significantly enriched levels of L-lysine, the most limiting essential amino acid, vitamin B3, vitamin B6, improved protein quality and flavor, and largely eliminated indigestible sugars. CONCLUSION: The fermented sunflower seed milk, obtained by using two food-grade microbes without further supplementation, displays an attractive, clean-label product with a high level of vitamin B12 and multiple co-benefits. The secret of the successfully upgraded plant milk lies in the multifunctional cooperation of the two microbes, which were combined, based on their genetic potential and metabolic signatures found in mono-culture fermentations. This design by knowledge approach appears valuable for future development of plant-based milk products.


Asunto(s)
Bacillus amyloliquefaciens , Propionibacterium freudenreichii , Animales , Técnicas de Cocultivo , Humanos , Leche , Semillas , Vitamina B 12 , Vitaminas/metabolismo
2.
Int J Food Sci Nutr ; 72(2): 236-247, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32631124

RESUMEN

This study evaluated the validity of nutrient and food group intakes estimated by an FFQ against biomarkers. A 71-item semiquantitative FFQ was administered to 210 Brazilian children and adolescents aged 9-13 years. Intakes were correlated with biomarkers in plasma and red blood cells. Correlations between nutrients and their biomarkers were presented for animal protein, myristic acid (C14:0), EPA, DHA, ß-carotene, folate, and vitamins B3, B5 and B6. Food groups and biomarkers were correlated as follows: fish products with EPA and DHA; milk and dairy with C14:0, pyridoxal 5'-phosphate and vitamin B12; total vegetables and dark green and orange vegetables with ß-carotene; 5-methyltetrahydrofolate with green vegetables; and flour products with para-aminobenzoylglutamic acid. This FFQ is a valid tool for ranking Brazilian children and adolescents according to their intake of several nutrients and food groups.


Asunto(s)
Biomarcadores/sangre , Encuestas sobre Dietas , Adolescente , Brasil , Niño , Femenino , Ácido Fólico/sangre , Humanos , Masculino , Encuestas y Cuestionarios , Vitaminas/sangre , beta Caroteno/sangre
3.
J AOAC Int ; 98(6): 1697-701, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26651582

RESUMEN

In order to determine repeatability and reproducibility of AOAC First Action Method 2012.16 [Pantothenic Acid (Vitamin B5) in Infant Formula and Adult/Pediatric Nutritional Formula by Ultra-High Pressure Liquid Chromatography/Tandem Mass Spectrometry], a collaborative study was organized. The study was divided in two parts: method setup and qualification of participants (part 1) and collaborative study participation (part 2). For part 1, each participating laboratory was asked to analyze two practice samples using the aforementioned method. Laboratories that provided results within a range of expected levels were qualified for part 2, during which each laboratory received 10 samples in blind duplicates. Results have been compared to the Standard Method Performance Requirement (SMPR®) 2012.009 established for pantothenic acid. Precision results (repeatability and reproducibility) were within the limits stated in the SMPR. Repeatability ranged from 1.3 to 3.3%, and reproducibility ranged from 4.1 to 7.0%. Horwitz ratio (HorRat) values were all <1, ranging from 0.33 to 0.69. The AOAC Expert Review Panel on Stakeholder Panel on Infant Formula and Adult Nutritionals Nutrient Methods determined that the data presented met the SMPR and recommended the method for Final Action status, which was then granted by the AOAC Official Methods Board.


Asunto(s)
Cromatografía Liquida/métodos , Alimentos Formulados/análisis , Fórmulas Infantiles/química , Ácido Pantoténico/análisis , Espectrometría de Masas en Tándem/métodos , Adulto , Conducta Cooperativa , Humanos , Lactante
4.
J AOAC Int ; 97(4): 1121-6, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25145147

RESUMEN

A UHPLC-MS/MS method for the determination of folate (vitamin B9) in infant formula and adult/pediatric nutritional formula was assessed for compliance with standard method performance requirements set forth by the AOAC INTERNATIONAL Stakeholder Panel for Infant Formula and Adult Nutritionals (SPIFAN). A single-laboratory validation (SLV) study was conducted as the first step in the process to validate the method. In the study, 12 matrixes, representing the range of infant and adult nutritional products, were evaluated for folate [the sum of supplemental folic acid plus 5-methyl tetrahydrofolic acid (5-Me THF)]. Method response was linear in the range of 1.0-900 ng/mL, corresponding to 0.33-300 microg/l100 g in reconstituted sample. LOD for folic acid and 5-Me THF, expressed in reconstituted product, were 0.10 microg/100 g and 0.05 microg/100 g, respectively, and LOQ were 0.33 microg/100 g and 0.10 microg/100 g, respectively. Repeatability was <5.3% and intermediate precision was <5.5%. Recovery rates of spiking at 50 and 100% of target values in nonfortified products were within 90-110%. Evaluation of trueness was performed on Certified Reference Material (SRM 1849 Infant/Adult Nutritional Formula) and gave 96.4% of theoretical value. Based on the results of the SLV, the method meets the SPIFAN requirements for AOAC First Action status for the determination of folates in infant formula and adult/pediatric nutritional formula.


Asunto(s)
Ácido Fólico/análisis , Alimentos Formulados/análisis , Cromatografía Líquida de Alta Presión , Espectrometría de Masas en Tándem
5.
Food Chem ; 451: 139383, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38670025

RESUMEN

Foods are analysed for their vitamin content to support the verification of regulatory compliance or to generate food composition data. Many international reference methods for the analysis of vitamins in foods originate from the 1990s. Advances in nutrition science and analytical technology and the continuing evolution of statutory regulations necessitate the need of new or supplementary regulatory standards. We have evaluated recent developments in these areas and conclude that most current international reference methods are no longer fit-for-purpose to accurately determine vitamin content in foods and food supplements. We have made recommendations to consider new and/or updated reference methods and regulatory standards for the analysis of vitamins A, D, E, K, B1, B2, B3, B5, B6, B7, B9, B12, C and carotenoids in foods and food supplements. This area of nutrients may benefit from globally harmonised definitions specifying what compounds to include or exclude for analysis, and applicable bioactivity factors.


Asunto(s)
Análisis de los Alimentos , Vitaminas , Vitaminas/análisis , Análisis de los Alimentos/métodos , Valor Nutritivo , Humanos , Estándares de Referencia , Suplementos Dietéticos/análisis , Suplementos Dietéticos/normas
6.
J AOAC Int ; 96(5): 1065-7, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24282948

RESUMEN

During the AOAC Annual Meeting held in Las Vegas, NV from September 30 to October 3, 2012, the Stakeholder Panel on Infant Formula and Adult Nutritionals convened to review single-laboratory validation data submitted for the method, Vitamin C in Adult/Pediatric Formula by Ultra-Performance Liquid Chromatography with Ultraviolet Detection. This method is a modified version of the method "HPLC-UV Determination of Total Vitamin C in a Wide Range of Fortified Food Products" previously published in Food Chem., 94, 626-631 (2006). The SLV data from the modified method were reviewed and compared to the standard method performance requirements (SMPR 2012.012), and it was concluded that the method meets the requirements. The method was approved as AOAC Official First Action. The method is based on the acidic extraction of ascorbic acid in the presence of Tris[2-carboxyethyl] phosphine (TCEP) as a reducing agent. Separation was achieved on a C18 column with a sodium acetate eluent (pH 5.4) combined with TCEP and decylamine as an ion-pairing agent. Accuracy rates were between 90 and 100%. Repeatability RSD (RSD,) ranged from 1.4 to 2.5%, and intermediate reproducibility RSD (RSDiR) ranged from 1.3 to 7.5%.


Asunto(s)
Ácido Ascórbico/análisis , Cromatografía Líquida de Alta Presión/métodos , Alimentos Formulados/análisis , Fórmulas Infantiles/química , Reproducibilidad de los Resultados , Espectrofotometría Ultravioleta
7.
J AOAC Int ; 96(6): 1396-9, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24645520

RESUMEN

The method described below is for the determination of choline in infant formula and adult/pediatric nutritional formula by ultra high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). The single-laboratory validation data were submitted to the Stakeholder Panel on Infant Formula and Adult Nutritionals (SPIFAN) Expert Review Panel (ERP) for review at the AOAC INTERNATIONAL Annual Meeting held September 30 to October 3, 2012 in Las Vegas, NV. The ERP determined that the data reviewed met the standard method performance requirements set by SPIFAN, and the method was approved as AOAC Official First Action. The analytical range was found to be between 0.16 and 3.2 microg/mL. The recovery rates were within 80-120% at 50 and 100% of native levels for all samples. Repeatability precision (RSDr) was < 3%, with intermediate reproducibility (RSDir) no higher than 4%.


Asunto(s)
Técnicas de Química Analítica/normas , Colina/análisis , Cromatografía Líquida de Alta Presión/métodos , Alimentos Formulados/análisis , Fórmulas Infantiles/química , Espectrometría de Masas en Tándem/métodos , Adulto , Animales , Calibración , Cromatografía/métodos , Humanos , Hidrólisis , Lactante , Leche , Estándares de Referencia , Reproducibilidad de los Resultados , Glycine max
8.
Clin Nutr ; 42(12): 2443-2456, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-38411017

RESUMEN

BACKGROUND & AIMS: Optimal maternal vitamin status during pregnancy and lactation is essential to support maternal and infant health. For instance, vitamin D3 is involved in infant bone development, and B-vitamins are involved in various metabolic processes, including energy production. Through a double-blind randomised controlled trial, we investigated the effects of maternal supplementation from preconception throughout pregnancy until birth on human milk (HM) concentrations of vitamin D3 and B-vitamins. In addition, we aimed to characterise longitudinal changes in milk concentrations of these vitamins. METHODS: Both control and intervention supplements contained calcium, iodine, iron, ß-carotene, and folic acid, while the intervention also contained zinc, vitamins B2, B6, B12, and D3, probiotics, and myo-inositol. HM samples were collected across 4 time points from 1 week to 3 months post-delivery from 158 mothers in Singapore, and 7 time points from 1 week to 12 months from 180 mothers in New Zealand. HM vitamin D was quantified using supercritical fluid chromatography and B-vitamins with mass spectrometry. Potential intervention effects on HM vitamins D3, B2, B6, and B9, as well as other B-vitamin (B1 and B3) concentrations were assessed using linear mixed models with a repeated measures design. RESULTS: Over the first 3 months of lactation, HM 25-hydroxyvitamin D3 concentrations were 20% (95% CI 8%, 33%, P = 0.001) higher in the intervention group, with more marked effects in New Zealand. There were no observed intervention effects on HM concentrations of vitamins B1, B2, B3, B6, and B9. In New Zealand mothers, longitudinally, vitamin D3 concentrations gradually increased from early lactation up to 12 months, while vitamins B1 and B2 peaked at 6 weeks, B3 at 3 weeks, and B6 and B9 at 3 months. CONCLUSIONS: Maternal supplementation during preconception and pregnancy increased HM vitamin D, but not B-vitamin concentrations in lactation. Further studies are required to examine the discrete benefits of vitamin D supplementation starting preconception vs during pregnancy, and to further characterise the effects of supplementation on later offspring health outcomes. CLINICAL TRIAL REGISTRATION: Registered at ClinicalTrials.gov on the 16 July 2015 (identifier NCT02509988); Universal Trial Number U1111-1171-8056. This study was academic-led by the EpiGen Global Research Consortium.


Asunto(s)
Vitamina D , Vitaminas , Embarazo , Lactante , Femenino , Humanos , Vitaminas/análisis , Vitamina D/análisis , Leche Humana/química , Suplementos Dietéticos , Colecalciferol , Lactancia , Vitamina A/análisis , Método Doble Ciego
9.
J AOAC Int ; 95(2): 301-6, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22649910

RESUMEN

Vitamin A, a fat-soluble vitamin, is essential for health and plays an important part in vision, bone growth, reproduction, regulating the immune system, cell function, and skin health. Due to the advances in technology and the expansion of its uses, LC technologies are being studied for effectiveness in detecting and quantifying vitamin A in an effort to help determine the amount of vitamin A in various types of samples. For this reason, an Expert Review Panel agreed on June 29, 2011, at the "Standards Development and International Harmonization: AOAC INTERNATIONAL Mid-Year Meeting," to approve "Determination of Vitamin A in Infant Formula and Adult Nutritionals by UPLC-UV" as AOAC Official Method 2011.07. To move from First to Final Action status, it was recommended that additional information be generated for all types of infant formulas and adult nutritional formula matrixes at varied concentration levels, as indicated in the standard method performance requirements. International units or retinol equivalents typically represent the concentration of vitamin A in food and supplements. However, for the purpose of this method, the concentration represented is presented in microg/100 g.


Asunto(s)
Cromatografía Liquida/métodos , Alimentos Formulados/análisis , Fórmulas Infantiles/química , Vitamina A/química , Vitaminas/química , Adulto , Niño , Análisis de los Alimentos/métodos , Humanos , Lactante , Estándares de Referencia , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
10.
J AOAC Int ; 95(2): 307-12, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22649911

RESUMEN

At the "Standards Development and International Harmonization: AOAC INTERNATIONAL Mid-Year Meeting," on June 29, 2011, an Expert Review Panel agreed that the method "Determination of Vitamin B12 in Infant Formulas and Adult Nutritionals by Liquid Chromatography/UV Detection with Immunoaffinity Extraction" be adopted AOAC Official First Action status. The method is applicable for the determination of vitamin B12, which includes added cyanocobalamin and natural forms, making it applicable to both fortified and nonfortified products. Vitamin B12 is extracted from the sample in sodium acetate buffer in the presence of sodium cyanide (100 degrees C, 30 min). After purification and concentration with an immunoaffinity column, vitamin B12 is determined by LC with UV detection (361 nm). A single-laboratory validation study was conducted on a range of products, including milk- and soy-based infant formulas, cereals, cocoa beverages, health care products, and polyvitamin premixes. The method demonstrated linear response over a large range of concentrations, recovery rates of 100.8 +/- 7.5% (average +/- SD), repeatability RSD (RSDr) of 2.1%, and intermediate reproducibility (RSD(iR)) of 4.3%. LOD and LOQ values were 0.10 and 0.30 microg/100 g, respectively, and correlation with the reference microbiological assay was good (R2 = 0.9442). The results of the study were published in J. AOAC Int. 91, 786-793 (2008). The performance characteristics of the method met the standard method performance requirements set forth by the Stakeholder Panel on Infant Formula and Adult Nutritionals; thus, the method was determined to be appropriate for First Action status.


Asunto(s)
Cromatografía Liquida/métodos , Alimentos Formulados/análisis , Fórmulas Infantiles/química , Vitamina B 12/química , Vitaminas/química , Adulto , Niño , Análisis de los Alimentos/métodos , Humanos , Lactante , Extracción Líquido-Líquido , Estándares de Referencia , Reproducibilidad de los Resultados , Rayos Ultravioleta
11.
J AOAC Int ; 105(5): 1360-1366, 2022 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-35604099

RESUMEN

BACKGROUND: Since the publication of Standard Method Performance Requirements (SMPR®) for vitamin D in infant formula (SMPR 2011.004) by AOAC INTERNATIONAL, revised vitamin D limits have been recommended by the European Food Safety Authority (EFSA) for infant formula and adopted in Commission Delegated Regulation (EU) 2019/828. The vitamin D range introduced, 2-2.5 µg/100 kcal, is significantly narrower than previous limits specified by Codex Standard 72-1981 and requires lower method reproducibility metrics to adequately assess regulatory compliance. The narrower limits for vitamin D present a significant challenge for current-generation reference analytical methods that comply with SMPR 2011.004. OBJECTIVE: We evaluate the impact of Delegated Regulation (EU) 2019/828 on the demonstrated performance of AOAC Method 2016.05/ISO 20636:2018 to assess the likelihood that vitamin D results produced by the method would be found outside the EU limits when testing infant formula that is compliant as manufactured. METHODS: AOAC Method 2016.05/ISO 20636:2018, specifically data generated during multi-laboratory study, was used as a basis for statistical evaluation of the impact of the narrower EU vitamin D limits. RESULTS: The review of AOAC Method 2016.05/ISO 20636:2018 method performance against the vitamin D regulatory range introduced in (EU) 2019/828 indicates methods capable of performing in alignment with SMPR 2011.004 are likely to produce results that fail to meet EU requirements. CONCLUSIONS: Our assessment illustrates the high probability that a well-manufactured product with vitamin D levels within the EU regulatory range would fail to meet the regulatory requirements due to analytical method variability when tested using fit-for-purpose methods. Further, required method performance cannot be expected with the future development of new methods. To avoid this, consideration should be given to aligning proposed regulatory limits with method performance metrics of current-generation compendial methods. HIGHLIGHTS: Current, state-of-the-art methods cannot consistently verify infant formula product compliance for vitamin D in accordance with (EU) 2019/828.


Asunto(s)
Fórmulas Infantiles , Vitamina D , Alimentos Formulados , Humanos , Lactante , Fórmulas Infantiles/análisis , Reproducibilidad de los Resultados , Vitaminas
12.
Food Chem ; 362: 130197, 2021 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-34087716

RESUMEN

Vitamin B12 plays a key role in human biological functions and is vital in the neurological development of infants. The assessment of the vitamin B12 intake in exclusively breastfed babies depends on the reliability of its determination in milk. In this report, we present a new accurate and robust method for quantification of vitamin B12 in human milk. A highly specific sample preparation is applied, associated with chromatographic separation and detection by ICP-MS. Excellent sensitivity and accuracy are reported, with recovery values well within acceptability limits (80-120%), within- and between-day variability are lower than 10% and 15% respectively. Strong correlation with a microbiological assay was observed (r2 = 0.9) within the validation range (40-1000 pmol/L, corresponding to 54 to 1355 ng/L). The method can be used to routinely monitor vitamin B12 in clinical or population observational studies, determine infant's intake or assess efficacy of mother's supplementation.


Asunto(s)
Cromatografía Liquida/métodos , Espectrometría de Masas/métodos , Leche Humana/química , Vitamina B 12/análisis , Humanos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
13.
J AOAC Int ; 93(5): 1494-502, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21140662

RESUMEN

A fast and simple chromatographic method to determine biotin in foods is presented. Biotin is extracted using papain (60 degrees C, 1 h). After pH adjustment and filtration, biotin is determined by LC with fluorescence detection using postcolumn reagent avidin-FITC (avidin labeled with fluorescein isothiocyanate). The method has been validated in a large range of products: milk- and soy-based infant formulas, cereals, cocoa-malt beverages, and clinical nutrition products. The method showed recovery rates of 98.1 +/- 5.7% (average +/- SD) in a large range of concentrations. Biotin concentrations determined in infant formula standard reference materials 1846 and 1849 were in agreement with reference values. RSD of repeatability (RSDr) varied from 2.0 to 4.5%, and intermediate reproducibility (RSD(iR)) from 5.8 to 9.4%. LOD and LOQ were 3.0 and 5.0 microg/100 g, respectively. The proposed method is suitable for routine analysis of biotin in fortified foods (infant formulas, infant cereals, cocoa-malt beverages, and clinical nutrition products). It can be used as a faster, more selective, and precise alternative to the classical microbiological determination, and is easily transferable among laboratories.


Asunto(s)
Bebidas/análisis , Biotina/análisis , Cacao/química , Cromatografía Líquida de Alta Presión/métodos , Grano Comestible/química , Fórmulas Infantiles/química , Fluorescencia , Humanos , Lactante , Reproducibilidad de los Resultados
14.
Food Chem ; 333: 127447, 2020 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-32688304

RESUMEN

Quantification of the specific folate vitamers to estimate total folate in foods is not standardized. A collaborative study, including eight European laboratories, was conducted in order to determine the repeatability and reproducibility of the method for folate quantification in foods using the plant-origin γ-glutamyl hydrolase as part of the extraction procedure. The seven food samples analyzed represent the food groups; fruits, vegetables, dairy products, legumes, offal, fish, and fortified infant formula. The homogenization step was included, and six folate vitamers were analyzed using LC-MS/MS. Total folate content, expressed as folic acid equivalent, was 17-490 µg/100 g in all samples. Horwitz ratio values were within the acceptable range (0.60-1.94), except for fish. The results for fortified infant formula, a certified reference material (NIST 1869), confirmed the trueness of the method. The collaborative study is part of a standardization project within the Nordic Committee on Food Analysis (NMKL).


Asunto(s)
Fraccionamiento Químico/métodos , Ácido Fólico/análisis , Análisis de los Alimentos/métodos , Espectrometría de Masas en Tándem/métodos , Animales , Cromatografía Liquida/métodos , Cromatografía Liquida/normas , Productos Lácteos/análisis , Grano Comestible/química , Productos Pesqueros/análisis , Análisis de los Alimentos/normas , Alimentos Fortificados/análisis , Frutas/química , Humanos , Lactante , Fórmulas Infantiles/análisis , Reproducibilidad de los Resultados , Espectrometría de Masas en Tándem/normas , Verduras/química
15.
J AOAC Int ; 102(4): 1059-1068, 2019 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-30786951

RESUMEN

Background: Human milk is the optimal nutrition for all newborns in the first 6 months of life. In order to assess the nutritional needs of the breastfed infant, human milk is often characterized for multiple nutrients. Objective: To ensure that we minimize the volume of milk dedicated for research and optimize the number of nutrients characterized, we developed analytical methodologies for the determination of vitamins A (retinol), E (alpha and gamma tocopherol), K (phylloquinone and menaquinone-4), and five carotenoids (ß-carotene, lycopene, ß-cryptoxanthin, lutein, and zeaxanthin) using <1 mL human milk. Method: Vitamins E and K and carotenoids are simultaneously isolated from 750 µL milk by liquid-liquid extraction (LLE). Tocopherols and carotenoids are determined by normal-phase LC with fluorescence and ultraviolet detection respectively. Vitamin K is analyzed on the same extracts after resuspension and clean-up by reversed phase liquid chromatography coupled to tandem MS. The analysis of vitamin A involves saponification of 200 µL milk followed by LLE and determination by normal-phase LC with UV detection. Results: Full single-laboratory validation at four different concentration levels is presented. Recovery rates were within 90-105% in all except one case (retinol at 1.9 µg/mL, 88% recovery), with RSDs of repeatability and intermediate reproducibility below 10 and 15%, respectively for all the compounds. Conclusions and Highlights: To the best of best knowledge, this is the first report that allows for the characterization and quantification of vitamins A, E, and K and five carotenoids in <1 mL human milk.


Asunto(s)
Carotenoides/análisis , Cromatografía de Fase Inversa/métodos , Leche Humana/química , Vitamina A/análisis , Vitamina E/análisis , Vitamina K/análisis , Humanos , Reproducibilidad de los Resultados
16.
J Agric Food Chem ; 56(1): 260-5, 2008 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-18052039

RESUMEN

Chocolate is often labeled with percent cocoa solids content. It is assumed that higher cocoa solids contents are indicative of higher polyphenol concentrations, which have potential health benefits. However, cocoa solids include polyphenol-free cocoa butter and polyphenol-rich nonfat cocoa solids (NFCS). In this study the strength of the relationship between NFCS content (estimated by theobromine as a proxy) and polyphenol content was tested in chocolate samples with labeled cocoa solids contents in the range of 20-100%, grouped as dark (n = 46), milk (n = 8), and those chocolates containing inclusions such as wafers or nuts (n = 15). The relationship was calculated with regard to both total polyphenol content and individual polyphenols. In dark chocolates, NFCS is linearly related to total polyphenols (r2 = 0.73). Total polyphenol content appears to be systematically slightly higher for milk chocolates than estimated by the dark chocolate model, whereas for chocolates containing other ingredients, the estimates fall close to or slightly below the model results. This shows that extra components such as milk, wafers, or nuts might influence the measurements of both theobromine and polyphenol contents. For each of the six main polyphenols (as well as their sum), the relationship with the estimated NFCS was much lower than for total polyphenols (r2 < 0.40), but these relationships were independent of the nature of the chocolate type, indicating that they might still have some predictive capabilities.


Asunto(s)
Cacao/química , Flavonoides/análisis , Fenoles/análisis , Catequina/análisis , Cromatografía , Polifenoles , Teobromina/análisis
17.
J AOAC Int ; 91(4): 777-85, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18727537

RESUMEN

A single-laboratory validation study was conducted for a liquid chromatographic/mass spectrometric (LCIMS) method for the simultaneous determination of the free carnitine and total choline in milk-based infant formula and health-care products. The sample preparation used for both carnitine and choline was adapted from AOAC Official Method 999.14, with an acidic and enzymatic hydrolysis of esterified forms of choline. Carnitine and choline were quantified by ion-pair chromatography with single-quadrupole MS detection, using their respective deuterated internal standards. The repeatability relative standard deviation was < or =2.5 and 2.1%, respectively, for carnitine and choline. The intermediate reproducibility relative standard deviation was <4.7 and 2.4%, respectively, for carnitine and choline. The ranges of the average product-specific recoveries were 92-98 and 94-103%, respectively, for carnitine and choline. Choline concentration determined in infant formula reference material SRM 1846 was in agreement with the reference value. The proposed method was compared with the enzymatic methods for a range of products; good correlation (r = 0.99) was obtained, although a significant bias was observed for both analytes. The method, with a short chromatographic run time (7 min), is convenient for routine analysis to enhance analytical throughput and is a good alternative to enzymatic assays.


Asunto(s)
Carnitina/análisis , Colina/análisis , Alimentos Infantiles/análisis , Calibración , Cromatografía Liquida , Alimentos Fortificados/análisis , Humanos , Hidrólisis , Indicadores y Reactivos , Lactante , Espectrometría de Masas , Estándares de Referencia , Reproducibilidad de los Resultados , Soluciones
18.
J AOAC Int ; 91(4): 786-93, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18727538

RESUMEN

A fast and simple method to determine vitamin B12 in foods is presented. The method allows, in addition to the determination of added cyanocobalamin, the determination of natural vitamin B12 forms, making it also applicable to nonfortified products, especially those that are milk-based. Vitamin B12 is extracted in sodium acetate buffer in the presence of sodium cyanide (100 degrees C, 30 min). After purification and concentration with an immunoaffinity column, vitamin B12 is determined by liquid chromatography with UV detection (361 nm). The method has been validated in analyses of a large range of products: milk- and soy-based infant formulas, cereals, cocoa beverages, health care products, and polyvitamin premixes. The method showed appropriate performance characteristics: linear response over a large range of concentrations, recovery rates of 100.8 +/- 7.5% (average +/- standard deviation), relative standard deviation of repeatability, RSDr, of 2.1%, and intermediate reproducibility, RSDiR, of 4.3%. Limits of detection and quantitation were 0.10 and 0.30 microg/100 g, respectively, and correlation with the reference microbiological assay was good (R2 = 0.9442). The proposed method is suitable for the routine determination of vitamin B12 in fortified foods, as well as in nonfortified dairy products. It can be used as a faster, more selective, and more precise alternative to the classical microbiological determination.


Asunto(s)
Alimentos Fortificados/análisis , Vitamina B 12/análisis , Vitaminas/análisis , Cromatografía de Afinidad , Cromatografía Líquida de Alta Presión , Inmunoquímica , Indicadores y Reactivos , Estándares de Referencia , Reproducibilidad de los Resultados , Solventes , Espectrofotometría Ultravioleta
19.
Artículo en Inglés | MEDLINE | ID: mdl-29665470

RESUMEN

In the present manuscript, we describe a fully optimized and validated method suitable to analyse nine compounds (retinyl acetate, retinyl palmitate, retinol, α-tocopherol, α-tocopheryl acetate, cholecalciferol, ergocalciferol, phylloquinone, menaquinone-4) representing the major contributors to the fat-soluble vitamin activity of selected food products (infant formulas, adult nutritionals, infant cereals and mixed meals). Sample preparation involves direct solvent extraction using enzyme-assisted matrix disintegration and methanolic protein precipitation. Direct injection of the extract allows quantification of vitamins A, E and K in only 7 min, while vitamin D is determined after fast derivatization of the extract. Separation is achieved by supercritical fluid chromatography and detection performed by tandem mass spectrometry in positive Atmospheric Pressure Chemical Ionization mode. Results on a Standard Reference Material (SRM 1849a Infant/Adult Nutritional) were not statistically different from reference values. Full validation of the method showed excellent overall performance. Average recovery rate was between 90 and 110% for all vitamins and matrixes. The methodology shows enhanced safety and reduced cost as compared with previously published methods, together with potential for application to more complex matrixes. The full procedure can be easily applied in control laboratories dramatically increasing sample throughput and reducing solvent consumption.


Asunto(s)
Cromatografía con Fluido Supercrítico/métodos , Análisis de los Alimentos/métodos , Espectrometría de Masas/métodos , Vitaminas/análisis , Alimentos Congelados/análisis , Humanos , Lactante , Alimentos Infantiles/análisis , Modelos Lineales , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
20.
Food Chem ; 249: 91-97, 2018 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-29407937

RESUMEN

In the present study an optimization of trienzyme treatment combining α-amylase, protease and γ-carboxy peptidase allowing complete sample preparation within a working day for the analysis of vitamin B9 (folate) in infant formula and adult/pediatric nutritional products is presented. The optimized sample preparation was applied to a set of samples representing most of the products in the marketplace. Results on Standard Reference Material 1849a were well in agreement with certified values. The main contributor to total folate was folic acid, 5-methyl-tetrahydrofolate was the only minor contributor in milk-based products. Soy-based formulas contained polyglutamates of 5-formyl-tetrahydrofolate. The relative contribution of polyglutamates to the total folate content remained low in the types of product included in this study. The results suggest that a simple di-enzyme treatment could be enough for these products, nevertheless, this should be carefully evaluated prior to making a decision on the use of tri- or di-enzyme treatment.


Asunto(s)
Ácido Fólico/análisis , Fórmulas Infantiles/análisis , Amilasas/análisis , Alimentos Formulados/análisis , Humanos , Valor Nutritivo , Ácidos Pteroilpoliglutámicos/análisis , Tetrahidrofolatos/análisis
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