For the most curcumin, be sure to use turmeric rather curry powderâa study analyzing curcumin content in 28 spice products described as turmeric or curry powders found that pure turmeric powder had the highest concentration of curcumin, averaging 3.14% by weight.
The most common type of octane rating worldwide is the Research Octane Number (RON). RON is determined by running the fuel in a test engine with a variable compression ratio under controlled conditions, and comparing the results with those for mixtures of iso-octane and n-heptane.
Octane ratings. 1  Understanding octane ratings. 2  Octane rating is a measure of a fuel's ability to resist âknockâ. 3  The recommended octane rating for most vehicles is usually octane 87, but be sure to check your vehicle ownerâs manual.  In general, the octane needs of a vehicle align with the manufacturerâs recommendation.