Department of Processing and Food Engineering, Punjab Agricultural University, Ludhiana-141004
*Corresponding author: engg-gagan@pau.edu
Online published on 10 December, 2014.
Three samples of ginger (Zingiber officinale Roseo) were pretreated individually with hot water blanching, citric acid (0.5%) and KMS (0.5%).These were air-dried at 50, 60 and 70°C in an electrical drier. The time required to reduce the moisture from 719.67 to 13.11% (wb) at 50°C, 714.33 to 11.41% (wb) at 60°C and 706.45 to 9.94% (wb) at 70°C was 42, 56, 54 hrs, 42, 46, 44 hrs and 30, 34, 32 hrs for hot water, citric acid and KMS treated samples, respectively. Drying curves were fitted to Page model, Modified Page model and Newton model and were analyzed. Samples treated with citric acid and dried at 50°C reported maximum volatile oil (2.2%), minimum Δ E (5.93), rehydration ratio (1.68), and maximum sensory score (8.0 on 9.0 basis). Modified Page model recorded highest value of correlation coefficient (R2 =0.9978), minimum value of chi square (0.00024) and root mean square value (RMSE = 0.149).
Drying models, Ginger, texture, Volatile oil
