AOAC SPIFAN Nutrients ERP (December 7, 2022)

Amino-07 (SLV) 10-2022 FOR ERP USE ONLY DO NOT DISTRIBUTE

Samples A range of infant formulas from the SPIFAN II kit, NIST certified reference materials (CRM), and samples purchased from local supermarkets were used in this validation study (Table 2).

Table 2: Samples used during method validation

Taurine Fortified

Sample

Source

partially hydrolysed milk-based infant formula powder

SPIFAN kit KDOX966 SPIFAN kit CULF358 SPIFAN kit TJHR217 SPIFAN kit URTF231 SPIFAN kit NSRB999 SPIFAN kit LYNY751 NIST CRM 1869 b NIST CRM 1849a b

Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes No

bovine milk-based infant formula powder soy-based infant formula powder FOS/GOS infant formula powder a

child elemental powder low-fat adult nutritional

milk/whey/soy-based infant formula powder

milk-based infant formula powder

bovine milk-based infant formula powder ovine milk-based infant formula powder

Commercial c Commercial c Commercial c Commercial c

soy-based infant formula powder

A2-casein bovine milk-based infant formula powder

a FOS = fructooligosaccharide, GOS = galactooligosaccharide b certified reference material purchased from National Institute of Standards and Technology (Gaithersburg, MD) c commercially available product purchased at a local supermarket

The SMPR for amino acids was primarily developed for proteogenic α -amino acids which are present in much higher concentrations compared to taurine, a non-proteogenic β -amino acid, which is considered a micronutrient due to the trace concentrations required for the normal growth and development. No infant formula product available is manufactured with the high concentration of taurine at the upper ranges specified in the SMPR; therefore, an adult nutritional powder was spiked at the high concentrations necessary to demonstrate method compliance. Linearity A measurement procedure is linear when, over given concentration range, obtains test results which are directly proportional to the true amount of analyte in the sample. The linear range interval should extend beyond the bounds of upper and lower concentration of the analyte in samples [3]. The concentration range specified in SMPR 2014.013 is 0.5– 2500 mg hg − 1 ready-to-feed (RTF).