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OBJECTIVES: Orange wine is essentially white wine that is produced similarly to red wines, with skin-contact during maceration. Various polyphenols found in red wine may be contributing to the observed benefits on heart health. The objective is to identify if grape skin contact gives orange wine similar antioxidant properties as red wine, by comparing total polyphenols and antioxidant capacity of red, white, and orange wines. METHODS: Fifteen wine samples were analyzed in triplicates (4 red, 8 orange and 3 white wines). A set of orange, red and white wines from the same wineries and vintages were purchased and analyzed. Analysis consisted of total polyphenols, total antioxidant capacity, and color. Total polyphenols were measured using the Folin Ciocalteu method (gallic acid equivalent per liter (GA/L)), total antioxidant capacity was measured using the ORAC method (micromol of Trolox equivalent per mililiter (µmol TE/ml)) and color was measured using a colorimeter (Lab color scale). RESULTS: Total polyphenol content in orange wines (1259.2 + 138.9 mg GA/L) was 0.6 times of red wines (2239.4 + 156.9 mg GA/L) and 4.6 times higher than white wines (273.9 + 11.8 mg GA/L). Similarly, the antioxidant capacity of orange wine (12.2 + 1.9 µmol TE/ml) was 0.6 times of red wines (20.9 + 2.7 µmol TE/ml) and 2.3 times higher than white wines (4.9 + 0.9 µmol TE/ml). Differences in total polyphenols and antioxidant capacity between types of wines were significantly different (ANOVA, α = 0.05). Color of orange wines had great variability, ranging from pale to deep orange and confirmed by the 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 this variation, including grape variety, winery, methods of production and storage; only two countries have a legal definition of orange wine or skin-contact white wine, thus adding additional variability. CONCLUSIONS: This allows for understanding of the characteristics of orange wines, which may have a beneficial effect on heart health and how it compares with other wine styles. FUNDING SOURCES: California State University, Northridge.

Ropy and non-ropy strains of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus were studied with respect to their resistance to reduction of water activity in milk used to produce yogurt. Glycerol reduced the a w of the milk considerably, but it was less inhibitory to acid production than sucrose. The ropy strains did not show any advantage over nonropy ones when they were used to produce yogurt in milk with reduced a w ; their performance was similar to non-producer strains in terms of lactic acid production.