Abstract #22
Section: ADSA Dairy Foods Oral Competition (Graduate)
Session: ADSA Dairy Foods Graduate Student Oral Competition
Format: Oral
Day/Time: Monday 10:45 AM–11:00 AM
Location: 331
Session: ADSA Dairy Foods Graduate Student Oral Competition
Format: Oral
Day/Time: Monday 10:45 AM–11:00 AM
Location: 331
# 22
In vivo digestion of a model infant formula in piglets: Protein digestion pattern and physiological responses.
N. R Tari*1, M.Z. Fan2, M. Corredig1,3, 1Department of Food Science, University of Guelph, Guelph, ON, Canada, 2Department of Animal Biosciences, University of Guelph, Guelph, ON, Canada, 3Gay Lea Foods Research and Development, Guelph, ON, Canada.
Key Words: milk proteins, in vivo digestion, infant formula
In vivo digestion of a model infant formula in piglets: Protein digestion pattern and physiological responses.
N. R Tari*1, M.Z. Fan2, M. Corredig1,3, 1Department of Food Science, University of Guelph, Guelph, ON, Canada, 2Department of Animal Biosciences, University of Guelph, Guelph, ON, Canada, 3Gay Lea Foods Research and Development, Guelph, ON, Canada.
The objective of this work was to better understand the effect of milk protein composition and specifically, β-casein (β-cas) on the digestion behavior of a model infant formula. Three diets with similar metabolizable energy, total protein and other essential nutrients were formulated to meet specific nutritional requirements for 3 groups of 8 piglets, as an established model for human infants. The control diet contained whey proteins (WP), while 2 others contained 40:60 casein/WP ratio, but differing by 24% in β-cas amount. To modify the β-cas ratio, microfiltration was conducted on skim milk either at 7 or 22°C. The study was carried out in 2 blocks, euthanizing the piglets at 21 d of age, after either 60 or 120 min from the last meal. Electrophoretic analysis of digestate samples after the gastric stage showed a hard aggregate, with caseins extensively hydrolysed to peptides, while β-lg and a-la were still largely intact after 60 or 120 min of digestion. The microstructure and rheological properties of the gastric digesta were also distinct between the WP control and the 2 cas/WP model formulas. A wide pH range between 4.4 to 5.8 was measured for the piglets’ gastric contents, with no significant difference observed between diets nor digestion times. Piglets fed the formula containing caseins resulted in a higher (P < 0.05) average daily gain and daily food intake compared with the WP control formula. Food conversion efficiency was not significantly different among the 3 formulas. Piglets fed the higher β-casein formula showed a significantly lower secretion of IL-10, but higher section of IL-6 and TNF-a inflammatory cytokines in the proximal jejunum, compared with other diets. It was concluded that milk caseins, specifically β-cas, not only affect the physical properties of the gastric digesta but may also contribute to health performance and regulation of physiological responses of neonates. The research demonstrated the potential to design a new generation of infant formula based on microfiltered milk concentrates.
Key Words: milk proteins, in vivo digestion, infant formula
