Effect of Drying Methods on the Quality Characteristics of Fenugreek (<i>Trigonella foenum-graecum</i>) Greens

Abstract

Abstract Different drying methods were investigated for efficient dehydration of fenugreek (Trigonella foenum-graecum) greens for optimal retention of color and its constituents. Accordingly, hot air (HA, 40°C, 58–63% RH), low humidity air (LHA, 40°C and 28–30% RH), and radiofrequency (RF, 40°C, 56–60% RH) were explored for efficient drying of fenugreek greens. The three single-layer drying models (Exponential, Page, and Modified Page) tested showed excellent fit (R2 = 0.92–0.99) for all three drying methods. The time required for drying with LHA and RF was less (∼27%), as compared to HA drying. LHA-dried fenugreek had superior green color and a more porous and uniform structure than those obtained from RF and HA drying. Aqueous methanolic (60:40) extract of fenugreek greens dehydrated by LHA exhibited the highest radical scavenging activity. Dehydrated fenugreek greens showed good consumer acceptance as well as shelf life. Keywords: ß-caroteneAntioxidant activityDryingFenugreek greensMinerals ACKNOWLEDGMENTS We thank the Director, CFTRI, Mysore, India, for his keen interest in this work and the facilities provided. The financial support from CSIR, New Delhi, is gratefully acknowledged. Notes Mean values in a column with different superscripts differ significantly at p < 0.05 by LSD. Mean values in a column with different superscripts differ significantly at p < 0.05 by LSD. Values are expressed as mean ± Standard deviation. Mean values in a column with different superscripts differ significantly at p < 0.05 by LSD values are expressed as mean ± standard deviation.