Coordinated postharvest trait networks in green chilli, guava, and tomato: Multivariate insights into physicochemical, antioxidant, and mineral quality retention under household storage

Household refrigeration slows the deterioration of perishable produce, yet the physiological and biochemical mechanisms underlying nutrient retention and coordinated postharvest trait networks remain poorly understood. This study evaluated green chilli ( Capsicum frutescens ), guava ( Psidium guajava ), and tomato ( Solanum lycopersicum ) stored under ambient (25±2°C) and refrigerated (6±1°C) conditions over 12 days, applying multivariate and network analyses to clarify trait interactions shaping postharvest quality. Regression- and threshold-based analyses were incorporated to validate key predictors and classify quality status. Refrigeration at 6 °C preserved quality. By day 12, weight loss in green chilli was limited to 4.7% compared to 25.2% under ambient conditions, while tomato firmness declined by 43.6% versus 77.2%. Guava retained 68.5% ascorbic acid under refrigeration, markedly higher than 19.3% at ambient temperature. Mineral traits remained stable across all treatments. Network analysis identified two coordinated trait modules representing quality preservation and deterioration. Firmness emerged as a strong predictor of quality, with R 2 values ranging from 0.31 to 0.75 across crops. Firmness thresholds effectively identified unacceptable quality, supporting early detection of deterioration. Strong correlations between firmness and antioxidant retention (ascorbic acid r=0.84; total phenolics r=0.83) further established firmness as an integrative trait linking physicochemical, antioxidant, and mineral attributes. Across the 12-day period, produce maintained acceptable quality for up to 8 days under refrigeration and approximately 2 days under ambient storage. These findings provide mechanistic insights into coordinated postharvest responses and offer practical tools, including trait networks and firmness monitoring to enhance nutrient retention, preserve quality, and reduce household food waste. • Refrigeration extends shelf life from 2 to 8 days by slowing quality loss. • Two trait networks found: quality preservation and deterioration modules. • Firmness is a strong quality predictor, with R 2 from 0.35 to 0.75 across crops. • Firmness thresholds identify unacceptable quality and aid early detection • Integrated trait networks and firmness provide practical tools to reduce waste.