Novel value-added beef products provide improved product differentiation within the beef marketplace. This study evaluated the impacts of supplementing feeds with fermented winery by-products (WB) to produce the novel beef product labeled by industry as “wine-finished beef”. To evaluate the impact of this feed, a total of 69 Angus-Hereford X steers were placed in four pens (n=18,17,17,17), one replicate pen per treatment, and fed finishing rations containing equal amounts of either 6-7% WB or 6-7% water (Control; C) over a 143 day feeding period. Dietary treatments were not significantly different with respect to energy or chemical contents (P > 0.05). Interestingly, the average daily gains (ADG; kg*d^-1) of cattle did not differ between diets (P > 0.05); however, the ADG of all beef cattle changed over the feeding period (P < 0.0041). Cattle temperament, evaluated by measuring their flight speed, changed over time (P = 0.0097), but not between diets (P = 0.6938). Meat quality attributes including chemical, colour, and tenderness properties did not differ (P > 0.05) between diets with the exception of ground steak, which was darker (P = 0.0477) in cattle fed WB compared to C supplemented feeds, respectively. Supplementing cattle feeds with WB provides a new marketing stream for beef products with no observed differences to cattle behaviour, animal gains or meat tenderness.