. 2022 Oct 23;12(11):1032. doi: 10.3390/membranes12111032

Table 2.

Content of phenolic acids (mg/L) in the ultrafiltration retentates (VRR 6).

Name of the Compound	Feed Solution (Apple Juice)	Membranes
Name of the Compound	Feed Solution (Apple Juice)	UF1-PAN	UF10-PAN	UF25-PAN
Chlorogenic acid	35.67 ± 1.14 ^a	44.35 ± 1.02 ^b	43.60 ± 0.65 ^b,c	41.53 ± 1.11 ^c
Caffeic acid	5.78 ± 0.02 ^a	6.00 ± 0.23 ^a	6.21 ± 0.21 ^a	6.26 ± 0.22 ^a
p-Coumaric acid	1.61 ± 0.04 ^a	1.28 ± 0.03 ^b	1.61 ± 0.09 ^a	1.72 ± 0.08 ^a
Sum of phenolic acids	43.06	51.63	51.42	49.51

Note: Different lowercase letters (a–c) show significant differences between the content of phenolic acids of feed solution and retentates (p < 0.05).