Determination of β-Galactooligosaccharides (GOS) in Infant Formula and Adult Nutritionals: Single-Laboratory Validation, First Action 2021.01.

Background: β-Galactooligosaccharides (GOS) are typically used in infant formula and adult nutritionals as a source of nondigestible oligosaccharides, which may bring beneficial effects through modulation of the gut microbiota. However, suitable methods for the determination of GOS in products with a high background of lactose do not exist.

Objective: The aim of this work was to develop a method suitable for the determination of GOS in infant formula and adult nutritionals and demonstrate suitability through single laboratory validation.

Protein fingerprinting and quantification of β-casein variants by ultra-performance liquid chromatography-high-resolution mass spectrometry.

Infant formulations are constantly evolving as novel protein ingredients are added to make them more closely mimic the protein profile of human milk; however, precise analytical methods for characterizing and quantifying the major milk proteins in such formulations are currently lacking. This article describes an ultra-performance liquid chromatography-high-resolution mass spectrometry method for intact proteins that can efficiently detect, identify, and characterize the major milk proteins and their proteoforms (phosphorylation status, degree of glycation, genetic variants among others) in ingredients and final products, with an emphasis on detecting and quantifying specific genetic variants of β-casein in infant formulas. Method sensitivity allows detection of β-casein A1 in A2-based infant formulas with a limit of detection of 2% (grams of β-casein A1 per 100 g of total β-casein).