Protein Digestibility and Anti-inflammatory Activity of Processed Whey Protein Ingredients for Infant Formula

Area of Science:

• Food Science
• Protein Chemistry
• Nutritional Science

Background:

• Heat processing and storage alter protein structure, potentially affecting digestibility and bioactivity.
• Whey protein concentrate (WPC) and skim-milk-derived WPC (SPC) are used in infant formula.
• Microbial safety requires heat treatment for these ingredients.

Purpose of the Study:

• To evaluate the impact of heat treatment and storage on SPC.
• To compare heat-treated SPC (HT-SPC) and heat-stored SPC (HTS-SPC) with a reference WPC.
• To assess changes in protein structure, digestibility, and bioactivity.

Main Methods:

• SPC was subjected to heat treatment (80 °C, 30 s) and storage (37 °C for 6 weeks).
• Protein aggregates were analyzed.
• In vitro infant gastric and intestinal digestion models were used.
• Anti-inflammatory activity was assessed via NFκB pathway inhibition in THP-1 macrophages.

Main Results:

• Reducible aggregates formed in HT-SPC, HTS-SPC, and WPC, but not in control SPC.
• Infant intestinal conditions caused significant whey protein hydrolysis, unlike gastric conditions.
• WPC exhibited higher digestibility than SPC; heat treatment enhanced SPC digestibility.
• Digested proteins from all sources showed comparable anti-inflammatory activity.

Conclusions:

• SPC is less digestible than WPC, but heat treatment improves its digestibility.
• Heat treatment of SPC did not alter its anti-inflammatory bioactivity compared to WPC.
• Findings suggest heat-treated SPC is a viable alternative to WPC in infant formulas regarding digestibility and bioactivity.