RESUMEN
The method for "Determination of Total Folates in Infant Formula and Adult Nutritionals by Trienzyme Extraction and UPLC-MS/MS Quantitation" was submitted to the Folate Working Group for consideration for adoption as Official First Action by AOAC INTERNATIONAL. This method uses ultra performance liquid chromatography/tandem mass spectrometry (UPLC-MS/MS) to determine the total folates in infant formulas and adult nutritionals after trienzyme digestion. Deconjugation of the various folate polyglutamates to folate monoglutamates is achieved by using rat plasma conjugase after the sample digestion with protease and a-amylase during the trienzyme digestion process. This method shows linearity of folate concentrations in the range of 10-19 100 microg/100 g. Extension of the range to cover folate concentrations of 5-2 000 000 microg/100 g can be achieved with appropriate adjustment of the sample weight and SPE cleanup loading volume. The recoveries ranged from 94.10 to 101.34%.
Asunto(s)
Enzimas/química , Ácido Fólico/análisis , Análisis de los Alimentos/métodos , Alimentos Infantiles/análisis , Vitaminas/análisis , Algoritmos , Amilasas/química , Animales , Tampones (Química) , Cromatografía Líquida de Alta Presión , Indicadores y Reactivos , Espectrometría de Masas , Péptido Hidrolasas/química , Ratas , Estándares de Referencia , Extracción en Fase Sólida , gamma-Glutamil Hidrolasa/sangreRESUMEN
A colorimetric method for the determination of total antioxidant activity in a variety of foods and beverages was validated in both a single-laboratory validation and a collaborative laboratory validation study. The procedure involved extraction of the antioxidants directly into a methanol-water solution containing a known amount of 2,2'-diphenyl-1-picrylhydrazyl (DPPH), thus promoting the rapid reaction of extracted materials with DPPH. The reaction was monitored by spectrophotometric measurement of the absorbance loss at 517 nm. Antioxidant activity was quantified relative to a dilution series of vitamin E analog standards (Trolox), which were analyzed in parallel simultaneously with the food and beverage samples. The antioxidant activities of the samples ranged from 131 to 131 000 micromole Trolox equivalents/100 g. Statistical analysis of the results showed that nine of the 11 matrixes gave acceptable HorRat values, indicating that the method performed well in these cases. The acceptable matrixes include pomegranate juice, blueberry juice, carrot juice, green tea, wine, rosemary spice, ready-to-eat cereal, and yogurt. Two samples failed the HorRat test: the first was an almond milk that had an antioxidant level below the practical LOQ for the method; the second was a sample of canola oil with added omega-3 fatty acid that was immiscible in the reaction medium.
Asunto(s)
Antioxidantes/análisis , Bebidas/análisis , Compuestos de Bifenilo/química , Análisis de los Alimentos/métodos , Picratos/química , Cromanos , Frutas/química , Indicadores y Reactivos , Prunus/química , Estándares de Referencia , Reproducibilidad de los Resultados , Espectrofotometría Ultravioleta , Especias/análisis , Té/química , Verduras/química , Vino/análisis , Yogur/análisisRESUMEN
Background: The need for an updated reference method for folate was identified as a priority by the AOAC's Stakeholder Panel on Infant Formula and Adult Nutritionals (SPIFAN) in 2011. An Expert Review Panel (ERP) found AOAC Official MethodSM 2011.06 suitable for the purpose and approved it as a First Action Official Method. Objective: To determine the repeatability and reproducibility of Method 2011.06: Total Folate in Infant Formula and Adult Nutritionals by Trienzyme Extraction and LC-MS/MS Quantitation. Methods: A multilaboratory collaborative study was conducted. Eleven laboratories located in five countries participated and completed analysis of all multilaboratory testing (MLT) samples. The study was divided into two parts. In the first part, the laboratories analyzed two practice samples (blindly coded) using the updated folate Method 2011.06. The laboratories providing results within the expected range qualified for part two, in which they analyzed 11 MLT samples in blind duplicates. Results: The results were compared with the Standard Method Performance Requirements (SMPR 2011.006) established for folate. The precision results met the requirements stated in the SMPR for all of the samples. Repeatability and reproducibility relative standard deviations ranged from 3.5 to 6.6 and from 9.0 to 15.7%, respectively. Horwitz ratio values for all of the samples were well below 2 (0.61-1.06). Conclusions: The ERP determined that the method performance met the SMPR requirements in September 2017 after reviewing the presented MLT data. Highlights: The ERP recommended the method for Final Action status.
Asunto(s)
Cromatografía Liquida/métodos , Ácido Fólico/análisis , Fórmulas Infantiles/análisis , Espectrometría de Masas en Tándem/métodos , Adulto , Animales , Calibración , Humanos , Lactante , Recién Nacido , Masculino , Ratas , Reproducibilidad de los ResultadosRESUMEN
Cooking foods affords numerous food safety benefits. During heating, Maillard reaction products (MRPs) are formed. MRPs contribute sensory aspects to food, including color, taste, and texture. One MRP, acrylamide, has been implicated in negative health outcomes; however, emerging data suggests MRPs may also deliver certain health benefits. The food industry has taken steps to decrease acrylamide formation, but the perception that high levels of acrylamide compromise the nutritional benefit of certain foods has continued. Potatoes are susceptible to MRP formation during cooking but also are considered an affordable, high nutrient content food. In particular, potatoes contribute significantly to fiber and potassium intakes in the U.S. population, two nutrients of need. How, then, should potatoes be judged for effects on health? A structured evidence assessment was conducted to identify literature, specifically clinical trials, on MRPs from potatoes and health, as well as nutritional contribution of potatoes. The results indicate limited human clinical data are available on negative health outcomes of potato-based MRPs, whereas potatoes are important contributors of key nutrients, such as fiber and potassium. Therefore, a balanced benefit-risk approach is warranted in order to assure that decreasing consumption of certain foods, like potatoes, does not lead to unintended consequences of nutrition inadequacies.
RESUMEN
Twelve laboratories representing 4 countries participated in an interlaboratory study conducted to determine all-trans-veta-carotene and total beta-carotene in dietary supplements and raw materials. Thirteen samples were sent as blind duplicates to the collaborators. Results obtained from 11 laboratories are reported. For products composed as softgels and tablets that were analyzed for total beta-carotene, the reproducibility relative standard deviation (RSDR) ranged from 3.35 to 23.09% and the HorRat values ranged from 1.06 to 3.72. For these products analyzed for trans beta-carotene, the reproducibility relative standard deviation (RSDR) ranged from 4.28 to 22.76% and the HorRat values ranged from 0.92 to 3.37. The RSDr and HorRat values in the analysis of a beadlet raw material were substantial and it is believed that the variability within the material itself introduced significant variation in subsampling. The method uses high pressure liquid chromatography (LC) in the reversed-phase mode with visible light absorbance for detection and quantitation. If high levels of alpha-carotenes are present, a second LC system is used for additional separation and quantitation of the carotene species. It is recommended that the method be adopted as an AOAC Official Method.