Extractability of Curcuminoids Is Enhanced with Milk and Aqueous-Alcohol Mixtures

In this study, we evaluated the extractability of three curcuminoids (curcumin, demethoxycurcumin, and bisdemethoxycurcumin) from turmeric powder in several solvents using high-performance liquid chromatography (HPLC) with the diode-array detection method. These solvents include water, milk (homogenized, 2% reduced fat, low fat, fat free, soy, almond, coconut, and milkadamia), and aqueous ethanols (0%, 4%, 10%, 20%, 30%, 40%, 50%, and 100%). Ambient water was able to extract only 0.55 mg/g of curcuminoids, whereas warm water extracted more than four-fold higher amounts (2.42 mg/g). Almond, coconut, and milkadamia milk were able to extract only small amounts of curcuminoids at ambient temperatures (0.01-0.07 mg/g). The extractability of curcuminoids in these milk types did not improve, even in warm conditions (0.08-0.37 mg/g). Whereas dairy and soy milk extracted 6.76-9.75 mg/g of curcuminoids under ambient conditions, their extractability increased significantly in warm conditions by 30-100% higher (11.7-14.9 mg/g). The solubility of curcuminoids also varied remarkably in different proportions of aqueous-alcohol mixtures. With 4% ethanol, only 1.7 mg/g of curcuminoids were extracted, and the amounts improved with the increase in ethanol content up to 50% (32.2 mg/g), while 100% ethanol extracted a similar amount as 50% ethanol (34.2 mg/g). This study suggests that the extractability of curcuminoids from turmeric will be dependent on the type of diets consumed with the turmeric supplements.

Automated summary

This study evaluated the extractability of three curcuminoids from turmeric powder in different solvents. The results showed that warm water and dairy milk extracted higher amounts of curcuminoids compared to other solvents. The study suggests that the extractability of curcuminoids is dependent on the type of solvents and temperature conditions.