Desulphiting dried apricots by exposure to hot air flow

Sulphited dried apricots were exposed to hot air flows at 40, 50 and 60 °C and the removal of SO 2 was investigated as their moisture content fell from an initial value of 193.2 g kg −1 to a final value of 80–90 g kg −1 . A first‐order kinetic model was found for the removal of SO 2 between 40 and 60 °C. Temperature quotients ( Q 10 ) for the removal of SO 2 were 2.84 between 40 and 50 °C and 4.93 between 50 and 60 °C; the activation energy ( E a ) was 114.40 kJ mol −1 between 40 and 60 °C. Analysis of the kinetic data also suggested a first‐order reaction for non‐enzymatic browning, with Q 10 values of 2.34 between 40 and 50 °C and 5.36 between 50 and 60 °C and an E a value of 109.36 kJ mol −1 between 40 and 60 °C. Exposure of dried apricots to a 60 °C air flow resulted in a rate constant for brown pigment formation that was 12 and 5 times higher than those at 40 and 50 °C respectively. © 2002 Society of Chemical Industry