Table 5.

Total Phenolic/Flavonoid/Tannin Content of grape by-products used in broilers’ diets.

	Grape by-Products
	GGP	WYC	PE
TPC	193.2 ± 33.4	7.3 ± 0.5	10.0 ± 0.9
TFC	50.3 ± 0.8	2.02 ± 0.06	3.73 ± 0.02
TTC	319.5 ± 33.2	10 ± 1	9 ± 2

Concentrations are expressed as mg equivalents (E)/25 g dry material for GGP, as mg E/g starch feed additive from stem extract (PE), and as mg E/2 g dry material for wine lees (WYC). The results were expressed as mg Gallic Acid Equivalents (GAE), mg Quercetin Equivalents (QE), and mg Epicatechin Equivalents (EE) for the three assays, TPC, TFC, and TTC, respectively. All values are means ± standard deviation of three measurements.