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The article presents a study that determines the fructans in infant, adult, and pediatric nutritional formulas. It offers overview of the principle, apparatus and materials, and the preparation of standards and solutions in the study. It also outlines the result of the study as well as the calculations, validation protocol and accuracy of the findings.

AOAC First Action Method 2011.10, Vitamin B12 in Infant and Pediatric Formulas and Adult Nutritionals, was collaboratively studied. This method uses a pH 4.5 sodium acetate buffer and potassium cyanide at 105°C to extract and convert all biologically active forms of vitamin B12 present to cyanocobalamin; octylsilyl (C8) or C18 SPE cartridges to purify and concentrate cyanocobalamin; a combination of size-exclusion and RPLC to isolate cyanocobalamin; and visible absorbance at 550 nm to detect and quantitate cyanocobalamin in infant, pediatric, and adult nutritionals with vitamin B12 concentrations greater than 0.025 μg/100 g ready-to-feed (RTF) liquid. During this collaborative study, nine to 11 laboratories from eight different countries analyzed blind duplicates of 12 infant, pediatric, and adult nutritional formulas. Per the AOAC Expert Review Panel (ERP) on Stakeholder Panel on Infant Formula and Adult Nutritionals (SPIFAN) Nutrient Methods the method demonstrated acceptable repeatability and reproducibility and met SPIFAN Standard Method Performance Requirements (SMPRs®) for the majority of product matrixes analyzed. Vitamin B12 SPIFAN SMPRs for repeatability were ≤15% RSD at vitamin B12 concentrations of 0.01 μg/100 g RTF liquid and ≤7% RSD at vitamin B12 concentrations of 0.2-5.0 μg/100 g RTF liquid. Vitamin B12 SPIFAN SMPRs for reproducibility were ≤11% RSD in products with vitamin B12 concentrations ranging from 0.3 to 5.0 μg/100 g RTF liquid. During this collaborative study, the RSDr ranged from 2.98 to 9.77%, and the RSDR ranged from 3.54 to 19.5%. During previous single-laboratory validation studies, the method LOQ was estimated to be 0.025 μg/100 g RTF liquid. [ABSTRACT FROM AUTHOR]

AOAC First Action Method 2011.18, Myo-Inositol (Free and Bound as Phosphatidylinositol) in Infant and Pediatric Formulas and Adult Nutritionals, was collaboratively studied. With this method free myo-inositol and phosphatidylinositol bound myo-inositol are extracted using two different sample preparation procedures, separated by ion chromatography using a combination of Dionex Carbo Pac PA1 and MA1 columns with column switching, and detected with pulsed amperometry using a gold electrode. Free myo-inositol is extracted from samples with dilute hydrochloric acid and water. Phosphatidylinositol is extracted from samples with chloroform and separated from other fats with silica SPE cartridges. Myo-inositol is then released from the glycerol backbone with concentrated acetic and hydrochloric acids at 120°C. During this collaborative study, nine laboratories from five different countries analyzed blind duplicates of nine infant and pediatric nutritional formulas for both free and phosphatidylinositol bound myo-inositol, and one additional laboratory only completed the free myo-inositol analyses. The method demonstrated acceptable repeatability and reproducibility and met the AOAC Stakeholder Panel on Infant Formula and Adult Nutritionals (SPIFAN) Standard Method Performance Requirements (SMPRs®) for free myo-inositol plus phosphatidylinositol bound myo-inositol for all the matrixes analyzed. SMPRs for repeatability were ≤5% RSD at myo-inositol concentrations of 2-68 mg/100 g ready-to-feed (RTF) liquid. SMPRs for reproducibility were ≤8% RSD in products with myo-inositol concentrations ranging from 2 to 68 mg/100 g RTF liquid. During this collaborative study, repeatability RSDs ranged from 0.51 to 3.22%, and RSDs ranged from 2.66 to 7.55% for free myo-inositol plus phosphatidylinositol bound myo-inositol. [ABSTRACT FROM AUTHOR]

A single-laboratory validation (SLV) has been performed for a method that simultaneously determines choline and carnitine in nutritional products by ultra performance LC (UPLC)/MS/MS. All 11 matrixes from the AOAC Stakeholder Panel on Infant Formula and Adult Nutritionals (SPIFAN) were tested. Depending on the sample preparation, either the added (free, with a water dilution and filtering) or total (after microwave digestion at 120°C in nitric acid and subsequent neutralization with ammonia) species can be detected. For nonmilk containing products, the total carnitine is almost always equal to the free carnitine. A substantial difference was noted between free and total choline in all products. All Standard Method Performance Requirements for carnitine and choline have been met. This report summarizes the material sent to the AOAC Expert Review Panel for SPIFAN nutrient methods for the review of this method, as well as some additional data from an internal validation. The method was granted AOAC First Action status for carnitine in 2014 (2014.04), but the choline data are also being presented. A comparison of choline results to those from other AOAC methods is given. [ABSTRACT FROM AUTHOR]

This normal-phase HPLC method with postcolumn reduction and fluorescence detection allows for the quantitative determination of trans vitamin K1 in infant, pediatric, and adult nutritionals. Vitamin K1 is extracted from products with iso-octane after precipitation of proteins and release of lipids with methanol. Prepared samples are injected onto a silica HPLC column where cis and trans vitamin K1 are separated with an iso-octane-isopropanol mobile phase. The column eluent is mixed with a dilute ethanolic solution of zinc chloride, sodium acetate, and acetic acid, and vitamin K1 is reduced to a fluorescent derivative in a zinc reactor column. The resulting hydroquinone is then detected by fluorescence at an excitation wavelength of 245 nm and an emission wavelength of 440 nm. During a single-laboratory validation of this method, repeatability and intermediate precision ranged from 0.6 to 3.5% RSD and 1.1 to 6.0% RSD, respectively. Mean overspike recoveries ranged from 91.9 to 106%. The method demonstrated good linearity over a standard range of approximately 2-90 µg/L trans vitamin K1 with r² averaging 0.99995 and average calibration errors of <1%. LOQ and LOD in ready-to-feed nutritionals were estimated to be 0.03 and 0.09 µg/100 g, respectively. The method met AOAC Stakeholder Panel on Infant Formula and Adult Nutritionals Standard Method Performance Requirements® and was approved as a first action method at the 2015 AOAC Mid-Year Meeting. [ABSTRACT FROM AUTHOR]

AOAC First Action Method 2011.10, Vitamin B12 in Infant and Pediatric Formulas and Adult Nutritionals, was collaboratively studied. This method uses a pH 4.5 sodium acetate buffer and potassium cyanide at 105°C to extract and convert all biologically active forms of vitamin B12 present to cyanocobalamin; octylsilyl (C8) or C18 SPE cartridges to purify and concentrate cyanocobalamin; a combination of size-exclusion and RPLC to isolate cyanocobalamin; and visible absorbance at 550 nm to detect and quantitate cyanocobalamin in infant, pediatric, and adult nutritionals with vitamin B12 concentrations greater than 0.025 μg/100 g ready-to-feed (RTF) liquid. During this collaborative study, nine to 11 laboratories from eight different countries analyzed blind duplicates of 12 infant, pediatric, and adult nutritional formulas. Per the AOAC Expert Review Panel (ERP) on Stakeholder Panel on Infant Formula and Adult Nutritionals (SPIFAN) Nutrient Methods the method demonstrated acceptable repeatability and reproducibility and met SPIFAN Standard Method Performance Requirements (SMPRs®) for the majority of product matrixes analyzed. Vitamin B12 SPIFAN SMPRs for repeatability were ≤15% RSD at vitamin B12 concentrations of 0.01 μg/100 g RTF liquid and ≤7% RSD at vitamin B12 concentrations of 0.2-5.0 μg/100 g RTF liquid. Vitamin B12 SPIFAN SMPRs for reproducibility were ≤11% RSD in products with vitamin B12 concentrations ranging from 0.3 to 5.0 μg/100 g RTF liquid. During this collaborative study, the RSDr ranged from 2.98 to 9.77%, and the RSDR ranged from 3.54 to 19.5%. During previous single-laboratory validation studies, the method LOQ was estimated to be 0.025 μg/100 g RTF liquid.