This research investigated the instant controlled pressure drop‐assisted hot air drying (DIC) impact on Maillard reaction‐related components of apple slices, with freeze drying (FD) and hot air drying (AD) as control. DIC apple slices were significantly (*p < .05) differentiated from FD and AD apple slices by marked browning, high levels of 5‐hydroxymethylfurfural (5‐HMF), and fluorescence intermediary compounds (FIC). DIC processing reduced fructose by 18.95%–45.68% and glucose by approximately 50%, while, the free amino acid reduction was 80.7%–95.1% and the reduction of hydrolysable amino acid was 15.1%–65.9% in DIC drying. In multivariate analysis, the DIC apple slices were significantly (*p < .05) differentiated from fresh, FD, and AD apple slices by three principal components that explained 46.7%, 12.9%, and 10.5% variances, respectively. Also, DIC apple slices were characterized by the FIC, 5‐HMF, total free amino acid, and CIE a*, b* values. This research compared the Maillard reaction‐related components of DIC apple slices with that of FD and AD apple slices. The results revealed that DIC apple slices were significantly (*p < .05) differentiated from FD and AD apple slices by marked browning and high levels of 5‐HMF and FICs. This research would provide information on the Maillard reaction‐related properties of DIC drying apple products, and offer the reference on apple varieties selection for DIC apple slices production. Novelty impact statement This research compared the Maillard reaction‐related components of drop‐assisted hot air drying (DIC) apple slices with that of freeze drying (FD) and AD apple slices. The results revealed that DIC apple slices were significantly (*p < .05) differentiated from FD and AD apple slices by marked browning and high levels of 5‐hydroxymethylfurfural and fluorescence intermediary compounds. This research would provide information on the Maillard reaction‐related properties of DIC drying apple products, and offer the reference on apple varieties selection for DIC apple slices production.

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