Table 2.
Phenolic compounds identified and quantified (mg kg−1) in APF1–5 and AE using HPLC-DAD–MS/MS.
| mg kg−1 | APF1 | APF2 | APF3 | APF4 | APF5 | AE | F | p |
|---|---|---|---|---|---|---|---|---|
| Dihydrochalcones | ||||||||
| Phloretin | 0.77 ± 0.06 b | 0.70 ± 0.04 bc | 0.98 ± 0.03 a | 0.29 ± 0.02 d | 0.78 ± 0.00 b | 0.63 ± 0.05 c | 102.3 | <0.001 |
| Phlorizin | 215.1 ± 2.5 a | 194.5 ± 5.3 b | 227.3 ± 1.3 a | 112 ± 3.0 d | 165.8 ± 1.1 c | 158.9 ± 9.4 c | 240.4 | <0.001 |
| Total | 215.9 ± 2.5 a | 195.2 ± 5.3 b | 228.3 ± 1.3 a | 112 ± 3 d | 166.3 ± 1.3 c | 159.6 ± 9.4 c | 239.9 | <0.001 |
| Flavones | ||||||||
| Luteolin | 0.26 ± 0.01 a | 0.11 ± 0.01 c | 0.15 ± 0.01 b | 0.10 ± 0.01 c | 0.13 ± 0.01 bc | 0.11 ± 0.01 c | 89.1 | <0.001 |
| Apigenin-7-O-glucoside | 0.84 ± 0.05 b | 0.73 ± 0.02 bc | 1.01 ± 0.05 a | 0.68 ± 0.03 c | 0.47 ± 0.04 d | 0.69 ± 0.06 c | 49.6 | <0.001 |
| Apigenin | 0.48 ± 0.00 | 0.38 ± 0.04 | 0.46 ± 0.07 | 0.31 ± 0.01 | 0.41 ± 0.23 | 0.43 ± 0.21 | 0.6 | 0.675 |
| Chrysin | 0.19 ± 0.00 b | 0.18 ± 0.00 c | 0.22 ± 0.00 a | 0.13 ± 0.00 d | 0.11 ± 0.00 e | 0.12 ± 0.00 d | 702.9 | <0.001 |
| Total | 1.77 ± 0.07 a | 1.40 ± 0.07 ab | 1.84 ± 0.11 a | 1.22 ± 0.03 b | 1.12 ± 0.28 b | 1.35 ± 0.26 ab | 6.9 | 0.003 |
| Flavanones | ||||||||
| Eriodictyol | 0.18 ± 0.02 b | 0.13 ± 0.02 c | 0.26 ± 0.01 a | 0.11 ± 0.01 c | 0.21 ± 0.02 b | 0.21 ± 0.01 b | 34.0 | <0.001 |
| Naringenin | 0.24 ± 0.02 a | 0.18 ± 0.03 b | 0.21 ± 0.01 ab | 0.11 ± 0.00 c | 0.17 ± 0.00 b | 0.19 ± 0.01 ab | 20.2 | <0.001 |
| Naringin | 0.22 ± 0.01 d | 0.57 ± 0.02 a | 0.60 ± 0.01 a | 0.48 ± 0.02 b | 0.35 ± 0.02 c | 0.46 ± 0.02 b | 195.0 | <0.001 |
| Total | 0.64 ± 0.01 d | 0.88 ± 0.01 b | 1.07 ± 0.01 a | 0.70 ± 0.03 c | 0.73 ± 0.04 c | 0.86 ± 0.00 b | 177.5 | <0.001 |
| Flavonols and Flavonol Glycosides | ||||||||
| Quercetin | 14.2 ± 3.0 a | 10.9 ± 2.4 ab | 13.1 ± 3.3 ab | 7.2 ± 1.8 bc | 4.10 ± 0.74 c | 12.7 ± 1.8 ab | 8.6 | 0.001 |
| Quercetin-3-O-rhamnoside | 121.9 ± 1.3 a | 85.3 ± 4.1 c | 124.8 ± 1.7 a | 114.1 ± 3.9 b | 34.1 ± 1.3 d | 85.9 ± 1.7 c | 512.7 | <0.001 |
| Quercetin-3-O-galactoside | 165.2 ± 3.5 a | 158.5 ± 2.7 a | 149.9 ± 4.1 b | 126.7 ± 3.4 c | 121.4 ± 0.6 c | 80.8 ± 1.8 d | 339.6 | <0.001 |
| Rutin | 46.93 ± 1.91 b | 20.37 ± 0.28 e | 23.9 ± 0.2 d | 64.86 ± 1.40 a | 7.99 ± 0.09 f | 34.46 ± 0.84 c | 1163.2 | <0.001 |
| Isorhamnetin-3-O-rutinoside | 1.11 ± 0.01 a | 0.82 ± 0.02 b | 0.41 ± 0.00 c | 0.40 ± 0.04 c | 0.36 ± 0.04 c | 0.10 ± 0.01 d | 703.8 | <0.001 |
| Isorhamnetin | 12.31 ± 0.43 b | 17.62 ± 0.31 a | 4.05 ± 0.04 c | 2.08 ± 0.02 d | 1.10 ± 0.01 e | 1.16 ± 0.02 e | 3037.8 | <0.001 |
| Kaempferol | 2.46 ± 0.37 a | 0.71 ± 0.14 bc | 2.82 ± 0.37 a | 1.37 ± 0.16 b | 0.48 ± 0.02 c | 0.62 ± 0.42 bc | 37.1 | <0.001 |
| Kaempferol-7-O-glucoside | 0.05 ± 0.01 c | 0.03 ± 0.01 c | 0.70 ± 0.03 b | 1.19 ± 0.12 a | 0.11 ± 0.01 c | 0.13 ± 0.02 c | 251.7 | <0.001 |
| Total | 363.9 ± 7.8 a | 257.5 ± 7.3 c | 328.4 ± 8.6 b | 341.1 ± 7.4 b | 129.1 ± 2.5 d | 261.8 ± 4.4 c | 491.4 | <0.001 |
| Flavanonols | ||||||||
| Taxifolin | 0.16 ± 0.02 d | 0.46 ± 0.01 a | 0.33 ± 0.01 b | 0.33 ± 0.04 b | 0.24 ± 0.01 c | 0.21 ± 0.02 cd | 86.5 | <0.001 |
| Hydroxycinnamic acids | ||||||||
| Caffeic acid | 0.33 ± 0.02 a | 0.22 ± 0.03 b | 0.35 ± 0.05 a | 0.23 ± 0.01 b | 0.12 ± 0.00 c | 0.18 ± 0.00 bc | 39.7 | <0.001 |
| p-Coumaric acid | 0.32 ± 0.06 c | 0.44 ± 0.09 bc | 0.44 ± 0.03 bc | 0.76 ± 0.09 a | 0.57 ± 0.03 b | 0.51 ± 0.05 b | 17.5 | <0.001 |
| Ferulic acid | 23.80 ± 0.28 a | 23.43 ± 0.87 a | 13.24 ± 0.07 d | 23.48 ± 0.21 a | 19.48 ± 0.54 b | 15.86 ± 0.33 c | 281.1 | <0.001 |
| Sinapic acid | 7.20 ± 0.03 a | 4.29 ± 0.19 b | 2.97 ± 0.05 c | 2.78 ± 0.03 cd | 2.60 ± 0.01 d | 2.03 ± 0.05 e | 1464.3 | <0.001 |
| Chlorogenic acid | 224.4 ± 9.8 b | 214.3 ± 3.4 b | 308.3 ± 14.0 a | 89.0 ± 9.5 e | 185.7 ± 6.2 c | 126.6 ± 4.7 d | 237.4 | <0.001 |
| Total | 251.8 ± 10.1 b | 245.6 ± 3.9 b | 325.1 ± 14.1 a | 117.7 ± 9.5 e | 208.5 ± 6.4 c | 145.2 ± 4.6 d | 220.9 | <0.001 |
| Hydroxybenzoic acids | ||||||||
| Gallic acid | 4.53 ± 0.10 b | 2.22 ± 0.04 e | 4.80 ± 0.12 a | 3.20 ± 0.12 c | 3.20 ± 0.03 c | 2.54 ± 0.03 d | 450.4 | <0.001 |
| Protocatechuic acid | 28.61 ± 1.01 a | 7.29 ± 0.55 de | 21.15 ± 0.73 b | 6.58 ± 0.42 e | 17.22 ± 0.24 c | 8.69 ± 0.01 d | 686.9 | <0.001 |
| Ellagic acid | 19.70 ± 2.90 b | 14.17 ± 0.27 b | 24.04 ± 5.64 b | 22.88 ± 8.49 b | 22.49 ± 2.30 b | 75.2 ± 11.8 a | 35.5 | <0.001 |
| p-Hydroxybenzoic acid | 2.51 ± 0.10 b | 2.15 ± 0.38 b | 2.24 ± 0.15 b | 2.92 ± 0.53 b | 1.16 ± 0.17 c | 5.80 ± 0.09 a | 89.9 | <0.001 |
| Total | 55.4 ± 3.4 b | 25.8 ± 0.5 d | 52.2 ± 5.2 bc | 35.6 ± 9.4 cd | 44.1 ± 1.9 bcd | 92.3 ± 11.7 a | 35.6 | <0.001 |
| Coumarins | ||||||||
| Aesculin | 9.38 ± 0.37 b | 8.80 ± 0.36 bc | 10.67 ± 0.56 a | 7.96 ± 0.11 c | 9.68 ± 0.28 b | 5.53 ± 0.16 d | 81.8 | <0.001 |
| Others | ||||||||
| Resveratrol | 0.16 ± 0.01 d | 0.89 ± 0.02 a | 0.82 ± 0.01 b | 0.24 ± 0.02 c | 0.22 ± 0.02 c | 0.19 ± 0.03 cd | 869.1 | <0.001 |
| Pterostilbene | 0.19 ± 0.01 d | 0.90 ± 0.00 a | 0.70 ± 0.01 b | 0.35 ± 0.02 c | 0.29 ± 0.02 c | 0.20 ± 0.05 d | 478.3 | <0.001 |
| Pinocembrin | 0.39 ± 0.01 a | 0.32 ± 0.00 b | 0.22 ± 0.00 e | 0.25 ± 0.00 d | 0.29 ± 0.00 c | 0.22 ± 0.00 e | 938.6 | <0.001 |
| Total | ||||||||
| 899.9 ± 3.9 b | 736.1 ± 7.2 c | 948.6 ± 77.0 a | 619 ± 10 e | 560.5 ± 4.9 f | 668.6 ± 19.9d | 736.5 | <0.001 | |
* Values are presented as mean ± SD (n = 3). Data were subjected to one-way ANOVA (between-subjects factor. Type of apple pomace flour; six levels: APF1, APF2, APF3, APF4, APF5 and AE; degree of freedom for all parameters was 5), different superscripts within the same row indicate a significant difference of means, according to Tukey’s HSD test (p < 0.05).