January 16, 2026 | Applied Fruit Science |
This study conducted by the ICAR–Indian Agricultural Research Institute, India, addressed the need for rapid and nondestructive methods to assess fruit ripeness in response to growing demand for fresh, ready-to-eat produce. Guava (Psidium guajava L.) is highly valued for its nutritional quality but ripens quickly after harvest, making accurate ripeness evaluation important for quality control and loss reduction.
The study investigated the use of electrical impedance spectroscopy (EIS) as a noninvasive technique to estimate guava ripeness during postharvest storage. Changes in physical, biochemical, and sensory attributes were monitored over a 10-day period. Impedance showed a strong inverse relationship with the total soluble solids to titratable acidity (TSS/TA) ratio, allowing the development of a predictive model with high accuracy (R² = 0.965). As ripening progressed, fruits exhibited significant weight loss, reduced sphericity, increased TSS, decreased acidity, and corresponding changes in impedance magnitude and phase angle. These electrical responses reflected underlying microstructural and metabolic changes in the fruit. Sensory evaluation confirmed that consumer acceptance closely followed impedance-based ripeness trends.
The findings demonstrate that EIS provides a reliable, rapid, and nondestructive signature of guava ripeness, with strong potential for real-time postharvest quality assessment and improved supply chain management.





