Impact of Night and Day Harvesting on the Aroma Profile of Tokaj Wines in the Context of Sustainable Gastronomy

This study examines the impact of harvest-time temperature on the aroma composition and sensory expression of Hárslevelű wines from the Tokaj region, with particular re-levance to sustainable gastronomy, where freshness, aromatic precision and reduced technological inputs are increasingly prioritised. Grapes were harvested either at night under cool pre-dawn conditions (18 °C) or at midday during high-temperature (28 °C) exposure, and subsequently processed through controlled microvinifications using bi-oprotection with Metschnikowia pulcherrima, applied alone or in combination with SO₂. Volatile compounds were analysed by HS-SPME–GC–MS and interpreted through PLS-DA, while sensory evaluation followed OIV standards and was complemented by qualitative insights from fine-dining chefs. Night-harvested wines contained higher levels of fresh, floral and citrus-associated terpene- and ester-derived volatiles, whereas sun-harvested wines exhibited riper aromatic traits and higher perceived acidity. Bi-oprotection increased metabolic diversity and enhanced ester formation but did not eliminate the fundamental differences imposed by harvest temperature. Sensory results consistently showed that night-harvested wines displayed greater aromatic purity, freshness and overall harmony across treatments. These findings demonstrate that night harvesting, particularly when combined with bioprotection, supports the pro-duction of aromatically expressive, high-quality Tokaj wines in alignment with the principles of sustainable gastronomy.