Physico chemical quality evaluation of turmeric powder (Curcuma longa) stored at different temperatures

Abstract

Studies on storage of turmeric powder packaged in a three layered metalized polyester covers (12μ polyester + 12μ metalized polyester + 80μ polyethylene (LDPE)) and stored at different temperatures like ambient, 30, 40 and 50 °C in different BOD incubators for a storage period of 10 weeks were studied. The results of the study indicated that the moisture content of turmeric powder reduced when stored at 30, 40 and 50 °C and maximum reduction of moisture content was 17.49% when stored at 50 oC. While for ambient stored turmeric powder, the moisture content was found to increase by 7.34%. There was no change in essential oil content of turmeric powder at ambient and 30 °C which was maintained at 4% in both the cases. But a reduction in essential oil content by 10% was observed at 40 and 50 °C towards the end of the storage period. A decrease in oleoresin content with increase in storage temperature was observed and the minimum reduction of 8.50% was obtained for the ambient stored turmeric powder and maximum reduction of 19.76% was observed when stored at 50 °C. Curcumin content reduced by 4.58%, 6.26%, 7.33% and 10.38% for ambient, 30, 40 and 50 °C storage conditions, respectively towards the end of 10 weeks of storage. Volatile oil constituents in the essential oil of turmeric powder like α-terpineol, zingiberene decreased during storage while constituents like ar-curcumene and curlone, ar-tumerone increased during the storage of turmeric powder.