. 2024 Apr 9;13(8):1138. doi: 10.3390/foods13081138

Table 4.

Qualitative analysis of phenolic compounds in seedless purple grapes subjected to various pretreatment methods.

Classification	Phenolic Substance	CK	DT	PT
Flavan-3-ol	(-)-Epigallocatechin gallate	ND	1860 ± 421 ^a	ND
	(-)-Epigallocatechin	19,407 ± 1182 ^c	23,611 ± 795 ^b	32,289 ± 555 ^a
	(+)-ProanthocyanidinB₂	3593 ± 153 ^b	3332 ± 79.16 ^b	7085 ± 778 ^a
	(+)-Galloctechin	2679 ± 164 ^b	2014 ± 39.61 ^b	4036 ± 258 ^a
Phenolic acids	Ferulic acid	3017 ± 149 ^a	2993 ± 232 ^a	4066 ± 260 ^a
	Vanillic acid	2981 ± 807 ^a	1437 ± 164 ^a	2076 ± 89 ^a
	Caffeic acid	1352 ± 127 ^a	ND	ND
	(E)-Ethyl caffeate	ND	1406 ± 149 ^a	1947 ± 270 ^a
	Coumaric	14,002 ± 386 ^a	13,406 ± 580 ^a	8248 ± 262 ^b
	Chlorogenic acid	2871 ± 81 ^b	2431 ± 536 ^b	8149 ± 1081 ^a
	Ethyl coumarate	13,925 ± 532 ^b	12,735 ± 466 ^b	20,739 ± 235 ^a
	Methyl gallate	1323 ± 57 ^a	1209 ± 16.81 ^a	1715 ± 58 ^a
	Methyl gallate-caffeine	ND	1862 ± 41.8 ^a	2761 ± 167 ^a
	3,5-O-dicaffeoylquinic acid	9279 ± 379 ^b	12,885 ± 529 ^b	32,698 ± 853 ^a
	Homovanillic acid	ND	ND	5092 ± 394 ^a
	Cinnamic acid	69,563 ± 2310 ^b	31,739 ± 456 ^c	93,704 ± 1839 ^a
	Benzoic acid	4108 ± 191 ^a	4056 ± 122 ^a	1877 ± 41 ^b
	Shikimic Acid	ND	1225 ± 21 ^a	1805 ± 252 ^a
	Sinapic acid	18,195 ± 1657 ^b	17,470 ± 2153 ^b	25,869 ± 8250 ^a
	Syringic acid	14,311 ± 1296 ^b	8703 ± 1385 ^c	20,469 ± 606 ^a
Flavonols	Dihydrokaempferide	ND	2296 ± 169 ^b	4207 ± 592 ^a
	Dihydroquercetin-3-o-rhamnoside	ND	1268 ± 56.4 ^a	ND
	Hyperoside	13,866 ± 783 ^a	12,914 ± 289 ^a	8628 ± 253 ^b
	Isohamnetin	34,812 ± 1107 ^a	37,719 ± 216 ^a	26,762 ± 621 ^b
	Isorhamnetin-3-glucoside	13,019 ± 603 ^a	12,614 ± 458.6 ^a	8896 ± 420 ^b
	Galangin	1321 ± 62 ^a	ND	ND
	Morin	50,490 ± 4038 ^b	55,914 ± 1846.7 ^b	119,447 ± 1575 ^a
	Myricetin	1792 ± 280 ^b	3581 ± 173 ^a	3517 ± 188 ^a
	Phlorizin	4480 ± 177 ^b	3843 ± 560 ^b	6652 ± 24 ^a
	Kaempferide	1571 ± 69 ^a	ND	1873 ± 13 ^a
	Naringenin	1234 ± 73 ^a	ND	ND
	Rutin	7784 ± 278 ^a	5189 ± 52.9 ^b	7231 ± 519 ^a
	Syringet-3-galactoside	19,502 ± 806 ^a	16,814 ± 549 ^b	13,521 ± 581 ^b
	Glycine betaine	2217 ± 137 ^a	2150 ± 20 ^a	3563 ± 81 ^a
Stilbenes	Resveratrol	8798 ± 137 ^b	8993 ± 391 ^b	16,544 ± 440 ^a

Note: In the table, different lowercase letters within the same column denote a significant difference at p < 0.05. ND indicates not detected. CK: the control group; DT: the drying agent treatment group; PT: the drying agent treatment group.