The tristimulus color coordinates (L*, a*, b*) of e-TiO₂-NPs suspensions (0.5%, 1%, and 1.5% w/w) without or with the presence of the food matrix during each phase of in vitro digestion^a.

Food matrix	Digestion step	L*			a*			b*
		0.5%	1%	1.5%	0.5%	1%	1.5%	0.5%	1%	1.5%
Without	Before digestion	22.14 ± 0.04c	22.88 ± 0.07b	23.65 ± 0.00a	−0.52 ± 0.04d	−0.52 ± 0.04d	−0.47 ± 0.04c	0.06 ± 0.02a	−0.08 ± 0.01a	0.45 ± 0.02a
	Salivary step	21.97 ± 0.36c	26.77 ± 0.29d	30.48 ± 0.33b	−0.99 ± 0.06b	−1.30 ± 0.04a	−1.29 ± 0.03a	4.06 ± 0.06d	3.99 ± 0.02d	4.34 ± 0.13d
	Gastric step	21.43 ± 0.20b	23.73 ± 0.31c	36.21 ± 0.31d	−0.88 ± 0.05c	−1.11 ± 0.02c	−1.00 ± 0.04b	2.35 ± 0.03b	1.77 ± 0.02b	1.85 ± 0.02b
	Intestinal step	20.30 ± 0.02a	21.08 ± 0.26a	30.96 ± 0.14c	−1.06 ± 0.07a	−1.24 ± 0.09b	−1.29 ± 0.03a	2.99 ± 0.08c	2.33 ± 0.05c	2.52 ± 0.01c
With	Before digestion	22.96 ± 0.70*C	23.65 ± 0.02**B	27.81 ± 0.14**C	−0.65 ± 0.08**C	−0.62 ± 0.04**C	−0.63 ± 0.02**D	2.81 ± 0.05**A	3.13 ± 0.03**A	2.24 ± 0.01**A
	Salivary step	23.50 ± 0.04**C	26.71 ± 1.44C	29.33 ± 0.05**D	−0.85 ± 0.05**B	−0.87 ± 0.09**B	−0.89 ± 0.04**B	4.46 ± 0.05**D	4.45 ± 0.35*C	4.53 ± 0.02**D
	Gastric step	21.75 ± 0.65B	26.13 ± 0.13**C	24.60 ± 0.07**A	−0.70 ± 0.02**C	−0.86 ± 0.04**B	−0.76 ± 0.02**C	3.13 ± 0.06**B	3.13 ± 0.01**A	2.87 ± 0.03**B
	Intestinal step	20.52 ± 0.13**A	21.59 ± 0.22**A	25.85 ± 0.13**B	−0.96 ± 0.04*A	−1.23 ± 0.04A	−1.07 ± 0.04**A	3.87 ± 0.03**C	3.24 ± 0.03**B	3.30 ± 0.04**C

^aThe lower-case (a–d) and capital (A–D) letters indicate significant differences between digestive step in the absence and presence of the food matrix (P < 0.05). * indicates significant differences between the absence and presence of food matrix for each phase of digestion (*P < 0.05 and **P < 0.01).