Bioactive essential oils as sustainable postharvest technology: suppression of sprouting and preservation of physicochemical quality in cold-stored potato tubers

Sprouting during storage represents a principal postharvest constraint for potato ( Solanum tuberosum L.), driving physiological weight loss, quality deterioration, and severe loss of marketability. Furthermore, recent regulatory restrictions on synthetic suppressants, such as chlorpropham (CIPC), due to environmental and health concerns have intensified the global demand for natural, eco-friendly alternatives. This study evaluated clove, lavender, and mint essential oils (EOs) as sustainable, residue-free sprout suppressants and assessed their capacity to preserve tuber quality during long-term cold storage. Across two consecutive seasons (2020–2021), potato cv. Kingsman was stored at 10 °C and 95% relative humidity for six months and treated via monthly thermal fogging at 50, 100, and 150 ppm (expressed as v/v, μL oil L −1 air).All three EOs significantly improved physical and biochemical quality attributes relative to untreated control tubers (P ≤ 0.05) in a distinct concentration-dependent manner. Clove oil applied at 150 ppm was consistently the most effective treatment, drastically reducing the sprouting percentage to 0.7–1.1% (compared to 100% in controls), limiting sprout length to 0.3–1.0 mm, and constraining physiological weight loss to 0.59–0.72% (versus 4.17–4.30% in controls). Furthermore, this treatment successfully sustained tuber firmness, dry matter, starch content, and general phenotypic appearance. Mint and lavender oils yielded comparable but slightly weaker suppressive responses at the identical concentration. Histological analysis identified the mechanistic basis of this effect, demonstrating that the applied EOs arrested sprout development by inducing progressive necrosis and structural disruption of the apical meristem within the tuber buds. Treated tubers further exhibited markedly lower accumulation of reducing sugars, indicating preserved processing quality and reduced acrylamide-formation potential during cold storage. Collectively, these findings establish plant-derived volatiles particularly clove oil at 150 ppm as highly effective, residue-free, and environmentally compatible alternatives to synthetic sprout inhibitors in commercial potato storage systems.