Comparative and synergetic effects of cold plasma and ozone treatments on microbial safety, color stability, and quality of chili during long-term storage

This study primarily emphasizes the comparative and synergistic effects of cold plasma (CP) and ozone (O₃)
treatments on microbial safety, surface and pigment-based color stability, and key quality parameters of Byadagi
chili during 16 weeks of ambient storage (27 ± 3 ◦C). Storage was identified as the principal factor contributing
to quality deterioration; however, pre-storage CP and O₃ interventions significantly mitigated these effects.
Samples were categorized into untreated (control), CP-treated, O₃-treated, and combined CP + O₃-treated groups.
The CP + O₃ combination achieved the most substantial microbial reductions by week 16, with decreases of
1.88 log₁₀ CFU g⁻¹ for total plate count, 1.36 log₁₀ CFU g⁻¹ for yeast and mold, and 1.05 log₁₀ CFU g⁻¹ for co-
liforms, relative to control. Although aflatoxin B₁ levels increased in all groups during storage, CP + O₃ main-
tained the lowest concentration (0.71 μg kg⁻¹) versus the control (6.32 μg kg⁻¹). Surface color was best preserved
in CP + O₃ samples (ΔE*: 3.80; a*: 19.21), with minimal change in chroma, hue, and browning index. Pigment
degradation was significantly lower in the CP + O₃ group: total carotenoids (5.8 % ↓), capsanthin (5.05 % ↓), and
American Spice Trade Association (ASTA) color value (26.2 % ↓), compared to greater losses in control samples.
While CP showed the highest antioxidant retention (phenolics: 84.7 %; DPPH: 83.4 %), CP + O₃ exhibited
balanced efficacy (phenolics: 80.5 %; DPPH: 82.1 %), with high sensory acceptability (Score: 7.45). In conclu-
sion, the synergistic CP + O₃ treatment effectively reduced storage-induced quality degradation, providing a
residue-free strategy for enhancing safety, visual quality, and nutritional attributes in high-value chili. Future
research should focus on industrial-scale applications and regulatory compliance.