EFFECTS OF TEMPERATURE AND TIME OF ROASTING ON THE PHYSICOCHEMICAL AND ANTIMICROBIAL CHARACTERISTICS OF CINNAMON BARK OIL

The purpose of the present study was to examine the influences of roasting and the effects of roasting temperature and duration on the chemical composition of cinnamon bark oil and to extend our knowledge concerning the changes in antioxidant activity, antimicrobial activity, physical properties such as colour, refractive index, density and contents of cinnamaldehyde and other components of cinnamon bark oil. Roasted Cinnamon barks were extracted using (40-60 ºC b.p) petroleum ether. Roasting increased the oil content of the cinnamon bark significantly (P<0.05). Maximum oil yield was observed at 100°c for 10 min (10.78 ± 0.03). Analysis of the extracted aromatic oils demonstrated a significant increase in antioxidant activity, total phenolic content, antimicrobial activity, density and also a significant decrease in refractive index and colour values for roasting periods of 10 to 30 min. An increase in the amounts of cinnamaldehyde of the roasted cinnamon bark oils was also found at 1800c for 10 min. However, during roasting 8-Allyl-8-methyl-3-Oxabicyclo [4.2.0] Oct-5-ene was generated. The results obtained lead to conclude that roasting at 80 ºC for 20 min, 100 °C for 20 minutes and 180 °C for 10 min would allow the development of the organoleptic properties of the oil without compromising its antioxidant activity.