Storage- and disorder-related metabolic changes in Chinese cabbage (Brassica rapa subsp. pekinensis) under modified atmosphere packaging and conventional storage by 1H NMR-based metabolomics

Chinese cabbage serves as the principal raw material for kimchi and is stored for extended periods during which physiological disorders such as midrib browning and internal blackening strongly reduce its quality and marketability. However, the metabolic changes accompanying these disorders, and the extent to which the storage method modulates them, have not yet been characterized. Employing a 1 H NMR-based untargeted metabolomics approach, this study investigated metabolic alterations associated with disorder development in the outer and inner leaves of Chinese cabbage ( Brassica rapa subsp. pekinensis ) stored under conventional (CV) and modified atmosphere packaging (MAP) conditions in a commercial-scale facility. Physiological status exerted a greater influence on the metabolome than storage method. Soluble sugars such as sucrose and raffinose declined markedly in disorder-affected cabbages, together with a broad range of amino acids including the branched-chain amino acids, lysine, and the aromatic amino acids, whereas the organic acids malate and fumarate and the osmolyte betaine increased. Glucosinolate composition shifted from alkenyl to indolic forms. Consistent with these quantitative shifts, pathway enrichment highlighted metabolic routes related to energy, nitrogen, aromatic amino acid, and glucosinolate metabolism, among which those associated with organic acid metabolism were affected only under CV storage. These perturbations were consistently less pronounced under MAP storage, and the outer and inner leaves responded in the same direction while differing in the magnitude of the changes. The current study provides a metabolic basis for the beneficial effect of MAP storage, supporting optimized strategies for the long-term storage of Chinese cabbage.