The effect of α- or β-casein addition to waxy maize starch on postprandial levels of glucose, insulin, and incretin hormones in pigs as a model for humans

Figures & data

Fig. 1.  Gelatinisation profile of 10% starch (

), 10% starch + 10% α-casein (

), and 10% starch + 10% β-casein (

); (x) represents temperature profile. Point A on the curve represents the on-set stage of pasting, B represents peak viscosity on heating, C represents viscosity at end of heating, D represents viscosity at end of cooling, and E represents the final viscosity of the paste.

Table 1. Pasting viscosities of treatments throughout gelatinisation.

	n	On-set pasting temp (°C) (a)	Peak viscosity on heating (Pa.s) (b)	End of heating (Pa.s) (c)	End of cooling (Pa.s) (d)	Final viscosity (Pa.s) (e)
10% starch	3	68.4^b	3.2^b	1.2^b	2.1^c	1.7^c
10% starch + 10% α-casein	3	74.7^a	1.7^c	0.5^c	4.3^b	4.8^b
10% starch + 10% β-casein	3	64.4	4.6^a	1.7^a	6.7^a	7.6^a
df^*		8	8	8	8	8

^a–cValues within column with different lowercase letters are significantly different (p < 0.05; Fishers’ test).

*degrees of freedom.

Fig. 2.  Postprandial blood glucose concentrations following ingestion of 10% starch (

), 10% starch + 10% α-casein (

) and 10% starch + 10% β-casein (

). ^(a-b)Values with different lowercase letters are significantly different (p < 0.05).

Table 2. Plasma GLP-1 concentrations (pmol/L) at T0 and T90 following ingestion of 10% starch, 10% starch + 10% α-casein, and 10% starch + 10% β-casein.

	10% starch (pmol/L)	10% starch +10% α-casein (pmol/L)	10% starch +10% β-casein (pmol/L)
T0	7.01	6.78	6.65
T90	7.87	7.34	7.04

Fig. 3.  (A) Plasma GIP concentrations following ingestion of 10% starch, 10% starch + 10% α-casein, and 10% starch + 10% β-casein. Preprandial GIP concentrations [horizontal], 30 min postprandial [slanted], and 90 min postprandial [vertical]. (B) Insulin concentrations (in plasma) following ingestion of 10% starch, 10% starch + 10% α-casein, and 10% starch + 10% β-casein. Preprandial insulin concentrations [horizontal], 30 min postprandial [slanted], and 90 min postprandial [vertical]. (C) Total amino acid levels of 10% starch, 10% starch + 10% α-casein, and 10% starch + 10% β-casein postprandial at T30 (slanted line) and T90 (vertical line).^(a-b)Values with different lowercase letters are significantly different from each other (p < 0.05).

Fig.4.  (A) Concentrations of free amino acids in plasma preprandial (T0) of 10% starch (

), 10% starch + 10% α-casein (

), and 10% starch + 10% β-casein (

). (B) Concentrations of free amino acids in plasma postprandial (T30) of 10% starch (

), 10% starch + 10% α-casein (

), and 10% starch + 10% β-casein (

). ^(a-b)Values with different lowercase letters are significantly different from each other (p < 0.05). (C) Concentrations of free amino acids in plasma postprandial (T90) of 10% starch (

), 10% starch + 10% α-casein (

), and 10% starch + 10% β-casein (

). ^(a,b,c)Values with different lowercase letters are significantly different from each other (p < 0.05).