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Figure 10. E-gram of infant formula 1 with sweet whey ingredient (60% whey claim).
Figure 11. E-gram of infant formula 2 with sweet whey ingredient (60% whey claim).
Figure 12. E-gram of infant formula 3 with α-Lac-enriched whey ingredient (65% whey claim).
property of proteins and depends on the proteins’ amino acid
sequence and molecular structure status. Unfortunately, no
literature is currently available regarding whey protein and
casein ratios under SDS-CGE conditions, nor for proteins after
infant formula processing. In contrast, the mass ratio of whey
proteins to caseins is well established (4, 5; Table 8) and can be
calculated as 26.9% (whey proteins versus caseins) in bovine
milk and SMP.
To correct for the difference between the mass-to-area ratios
of whey proteins and caseins, 13 SMP samples from different
batches and suppliers were analyzed by SDS-CGE with 50
measurements. The two whey protein areas and the one casein area
were integrated, and the area percentage ratio of whey proteins to
caseins was established at 20.8% (Table 9).
The mass-to-area CF for whey proteins relative to caseins
was obtained by comparing the whey-to-casein mass percentage
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