Ratios of four O-COMs with respect to CH₃OH in gas (data points) and ice (shaded regions). Gas ratios are collected from a total sample of nine low-mass sources from this work and literature (blue circles; Jørgensen et al. 2018; Manigand et al. 2020; van Gelder et al. 2020; Yang et al. 2021), and 14 high-mass sources from the coccoa survey (Chen et al. 2023). Ice ratios are available for only two protostars (IRAS 2A and B1-c; Rocha et al. 2024, this work) and one comet (67P/C-G; Rubin et al. 2019). All data of the two focused low-mass sources, NGC 1333 IRAS 2A and B1-c, are colored in orange and green, respectively. The gas ratios of IRAS 2A and B1-c derived in this work and previous observations are highlighted in stars and squares (Taquet et al. 2015; van Gelder et al. 2020), respectively. Upper limits are denoted by downward triangles or arrows.