Estimation of daily curcuminoid intake from commercial curry products

Turmeric, the main spice in curry, contains curcuminoids, which have been closely linked to the prevention of various chronic diseases. However, the daily intake of curcuminoids from curry consumption remains unclear. This study optimized an analytical method for quantifying individual curcuminoids and then applied it to 50 commercial curry samples available in the retail market. The curcuminoids namely curcumin, demethoxycurcumin, and bisdemethoxycurcumin, which provide the yellow color present in turmeric, were analyzed, and a daily curcuminoid intake from a curry-based diet was estimated. Prior to data collection, the analytical method, incorporating high-performance liquid chromatography with a diode array detector, was validated for linearity, limit of detection (0.03–0.04 mg/kg), limit of quantification (0.10–0.14 mg/kg), and precision and accuracy (less than a relative standard deviation of 1.25 %). Total curcuminoid content in the curry products tested varied greatly depending on the product type, ranging from 24.59 to 161.02 mg/100 g (mean 75.92 mg/100 g) for powdered curry and from 1.04 to 10.78 mg/100 g (mean 4.12 mg/100 g) for retorted curry (precooked curry packaged in a retorted pouch). The daily intake of total curcuminoids from curry products, estimated from the data in this study and available domestic consumption data, was 0.339 mg/person/day for males and 0.299 mg/person/day for females. The distribution of total curcuminoids varied greatly by product owing to variation in the turmeric contents used by curry manufacturers in individual products. The results reveal the wide variation in the curcuminoid contents of commercial curry products and provide information on daily curcuminoid intake.