Volatile organic components detection with SPME/GC-MS technology in various ripening banana peels

To distinguish banana ripening stages based on their volatile organic compounds (VOCs) and aroma properties, banana samples with different ripening processes were divided into five stages (green ripe, yellow ripe, browning stage 1, browning stage 2, and browning stage 3) based on digital images and the K-means clustering algorithm, and their VOCs were determined. A total of 35 VOCs were identified using solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS), including aldehydes, alcohols, esters, ketones, terpenoids, and other alkanes. Ten VOCs belonging to 7 aroma categories (pineapple, banana, fruity, apple, grass, sweet, and green aromas) were distinguished according to the radar fingerprint chart. Principal component analysis (PCA) and linear discriminant analysis (LDA) were used separately to analyze the differences and establish classification models based on the relative content of banana peel VOCs. For bananas at different ripening stages, PCA and LDA provided good discrimination accuracy based on the dataset. Therefore, banana peel VOCs and their aroma characteristics can serve as effective indices for evaluating the banana ripening stage.