Figures (7)  Tables (1)

    • Figure 1. 

      Evolution of the overall appearance of fresh-cut spearmint subjected to various low O2 treatments over a 14-day storage period.

    • Figure 2. 

      Physiological attribute alterations of cut spearmint during low-temperature storage (5 °C) in modified-atmosphere packaging with suppressed O2 concentrations. Firmness, N (a); lightness (b); a* value (c); b* value (d); Hue angle (e); and ΔE (f) of CIE colour space. Values are of 3 replicates and error bars represent standard errors.

    • Figure 3. 

      Principal component analysis (PCA). (a) Component loading plot and (b) covariance biplot of cut spearmint colour parameters during storage.

    • Figure 4. 

      Total phenolic content, mg gallic acid equivalent per 100 g FW (a), antioxidant activity (DPPH), mg Trolox equivalent per 100 g FW (b), total ascorbic acid, mg·100 g−1 FW (c), ammonia content, µg·g−1 (d), acetaldehyde, µmol·g−1 (e), and ethanol, µmol·g−1 (f) of cut spearmint during low-temperature storage (5 °C) in modified-atmosphere packaging with suppressed O2 concentrations. Values are of 3 replicates, and error bars represent standard errors.

    • Figure 5. 

      Principal component analysis (PCA). (a) Component loading plot and (b) covariance biplot of cut spearmint off-flavour parameters during storage.

    • Figure 6. 

      Multivariate analysis of spearmint quality during storage. (a) Hierarchical cluster analysis (HCA) dendrogram based on Euclidean distance and (b) cluster scatter plot providing a spatial visualisation of sample distribution along Dim1 (34.5%) and Dim2 (25.7%).

    • Figure 7. 

      Comprehensive volatile and metabolic profiling of spearmint during storage. (a) PCA variable biplot illustrating the correlation between specific volatile organic compounds (VOCs) and sample clusters. (b) Clustered heatmap providing a high-resolution visualization of chemical intensity across all treatment replicates.

    • Quality attributes Factor effects
      Treatment Storage time Treatment storage time
      Physiological attribute
      O2 availability *** * NS
      Weight loss (%) *** ** NS
      Texture (N) NS *** NS
      Colour
      Lightness * NS NS
      a* *** * *
      b* * NS NS
      Hue angle NS * *
      ΔE *** NS NS
      Phytochemical attributes
      Total phenolic content (mg gallic acid equivalent per 100 g FW) NS * NS
      Antioxidant capacity (DPPH) (mg Trolox equivalent per 100 g FW) NS * NS
      Total ascorbic acid (mg·100 g−1 FW) NS ** **
      Off-flavour attributes
      Ammonia content (µg·g−1) NS *** *
      Ethanol (µmol·g−1) NS * NS
      Acetaldehyde (µmol·g−1) ** *** ***
      The effect of each main factor and of their interaction is significantly different for p ≤ 0.05 (*); p ≤ 0.01 (**); p ≤ 0.001(***); or not significant (NS).

      Table 1. 

      Effects of main factors (low O2 treatments, time of storage and their interaction) on quality attributes of cut spearmint stored at 5 °C for 14 days.