Red, White, and Orange? A New Look into an Old Wine

Orange wine is essentially white wine that is produced the way red wine is produced, with skin-contact during maceration and fermentation. Various polyphenols found in red wine may contribute to the observed benefits on heart health. The objective of this study is to identify if grape skin contact gives orange wine similar antioxidant properties that it provides to red wine, by comparing total polyphenolic content (TPC) and antioxidant capacity of red, white, and orange wines. Fifteen wine samples were analyzed in triplicates. Analysis consisted of TPC, total antioxidant capacity, and color. TPC was measured using the Folin Ciocalteu method (gallic acid equivalent per Liter (GA/L)), total antioxidant capacity was measured using the Oxygen Radical Absorbance Capacity (ORAC) method (micromolar of Trolox equivalent per Liter (µmol TE/L)) and color was measured using a colorimeter (HunterLab color scale). TPC in orange wines (1305.36 ± 747.82 mg GA/L) was 0.5 times of red wines (2463.88 ± 533.53 mg GA/L) and 4.8 times higher than white wines (273.94 ± 35.56 mg GA/L). Similarly, the ORAC of orange wine (12822.07 ± 1329.72 µmol TE/L) was 0.7 times of red wines (19496.29 ± 974.14 µmol TE/L) and 4 times higher than white wines (3197.55 ± 574.85 µmol TE/L). Differences in TPC and antioxidant capacity between wine types were significantly different (ANOVA, ⍺=0.05). Color of orange wines had great variability, ranging from pale to deep orange and confirmed by the reading of the color scale with a wide range of a and b color values (0.3 to 2.9 and 13.3 to 25.5 respectively). Many factors can contribute to the variation in total polyphenols, ORAC value, and color, including duration of skin contact, grape variety, vintage, appellation, and other methods of production and storage; however only two jurisdictions have a legal definition of orange wine, or skin-contact white wine, thus adding additional variability. Through comparing the different wine styles' characteristics, orange wine is better understood. This study allows for a better understanding of the characteristics of orange wines by comparing them to other wine styles, which may have similar cardioprotective benefits as red wines.