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Proteomic analysis of the peptic and pancreatic digests of infant formula ingredients

ABSTRACT: Whey protein and serum protein concentrate (WPC, SPC) are infant formula (IF) ingredients. SPC was produced under different processing conditions. SPC; heat-treated (80 degree, 30 s) SPC (HT-SPC); heat-treated and stored SPC (six weeks at 37 degree, HTS-SPC) were compared to a whey protein concentrate (WPC), as a control. Whey protein-based IF ingredients (SPC, HT-SPC, HTS-SPC, WPC) were dissolved in Milli-Q water (Millipore Corp., MA, USA). Protein (0.5 g) was dissolved in 33.3 mL Milli-Q water to a final protein concentration of 15 mg/mL. Samples were subjected to in vitro digestion using pepsin followed by pancreatin to simulate infant gastric and intestinal digestion. For pepsin digestion, the pH was adjusted to 4 by 1 M HCl and pepsin (Sigma P7000) was added at a protein/enzyme of 1.25% (w/w). After pepsin digestion for 2 h, 1% of Pepstatin A (1 mg/mL, Sigma 77170) was added to terminate the reaction. The pH was then adjusted to 6.5 by 1.43 M sodium bicarbonate (Fluka, Roskilde, Denmark) and pancreatin (Sigma P7545) was added at a protein/substrate ratio of 1.5% (w/w). After pancreatic digestion for 6 h, 100 micro liter of cOmplete Protease inhibitor cocktail (1 tablet in 25 mL of Milli-Q water, Roche, Basel, Switzerland) was added to terminate the reaction.

INSTRUMENT(S): LTQ Orbitrap

ORGANISM(S): Bos Taurus (ncbitaxon:9913)

SUBMITTER: Yuhui Ye

PROVIDER: MSV000089298 | MassIVE | Fri Apr 22 06:24:00 BST 2022

REPOSITORIES: MassIVE

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Proteomic analysis of the peptic and pancreatic digests of infant formula ingredients

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