Application of fermented rose–mulberry fruit composite to enhance the antioxidant capacity, flavor, and sensory characteristics of mulberry wine

Fruit wine made from a single fruit often lacks sufficient color, flavor complexity, and nutritional balance. In this study, we enhanced the sensory and functional qualities of mulberry wine through co-fermentation with <i>Rosa rugosa</i> petals. The rose fermentation wort was prepared by mixing rose petals and water at a 1 : 40 (w/w) ratio, and blended with mulberry pulp at a 1 : 1 (w/w) ratio prior to enzymatic treatment with pectinase. To comprehensively evaluate the effects of co-fermentation, a combination of analytical techniques was employed: the electronic nose (E-nose) and electronic tongue (E-tongue) were used to characterize overall aroma and taste profiles, while headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) was used to identify and quantify volatile aroma compounds. Nutritional composition and <i>in vitro</i> antioxidant activity were determined <i>via</i> standard biochemical assays, including DPPH and hydroxyl radical scavenging evaluation. This study aimed to elucidate how co-fermentation affects the antioxidant capacity, sensory characteristics, and flavor complexity of rose-mulberry wine compared to monovarietal mulberry and rose wines. The results showed that rose-mulberry wine exhibited significantly higher DPPH radical scavenging ability, hydroxyl radical scavenging activity (HRSA), hue angle (CH), and softness index (SI) compared to mulberry wine (<i>P</i> < 0.05). The E-tongue and E-nose indicated that rose-mulberry wine shared a closer flavor profile with rose wine, distinctly separating it from the more acidic and bitter profile of mulberry wine. GC-MS analysis identified 98 volatile compounds across the three wine varieties. Notably, rose-mulberry wine retained key volatile characteristics of mulberry wine, while co-fermentation significantly enhanced the presence of esters, alcohols, ketones, furans, pyrans, phenols, and others. Among these, newly identified esters such as isoamyl acetate, ethyl 9-decenoate, and ethyl undecanoate contributed distinct fruity and floral notes. In summary, rose-mulberry wine successfully integrates the unique aromatic traits of <i>R. rugosa</i> petals and mulberry fruit, producing a beverage with enhanced sensory complexity, functional antioxidant capacity, and improved overall acceptability.