This study aimed to encapsulate cold-pressed horseradish leaf juice within maltodextrin/alginate (MD/AL), maltodextrin/guar gum (MD/GG), and maltodextrin/gum Arabic (MD/GA) by spray-drying, to characterize the encapsulates, and to test their potential as mayonnaise oxidation-preventing ingredients. The encapsulates exhibited desirable physicochemical, morphological, structural, and thermal properties, highlighting MD/GA-containing encapsulates, especially regarding high encapsulation yield (78.50 %). Also, encapsulates contained a significant amount of phenolics, which were stable during freezer storage. The encapsulates successfully delayed the mayonnaise oxidation: 31.91–38.94 % more than the synthetic antioxidant ethylenediaminetetraacetic acid, especially highlighting MD/AL-containing encapsulates. Also, the encapsulates improved product quality with a higher pH and lower acidity after storage compared to the controls. Overall acceptability of encapsulates-containing mayonnaises and commercial mayonnaise did not differ significantly. This study contributes to sustainable development by providing new insights into the valorization of horseradish leaves, as a promising alternative to synthetic additives to prolong the oxidative stability and shelf-life of high-oil-containing foods.