Hempseed oil burns hot in the germinating seed. This may explain hemp's ability to germinate and grow early in cold spring soil, allowing the crop to get a jump on weeds which it will progressively smother and eliminate. Normal Germination Temperatures of Selected Crops Plant oils are extremely variable. For one thing, to the plant these oils are fuel for burning. So plants tend to tolerate a lot of variation in the chemical make up of their seed oils, and they respond readily to breeding selection for higher or lower proportions of particular fatty acids.
Oils are triglycerides.
Off the three carbons of the glycerine backbone extend carbon chains of fatty acids. The same features which give hemp oil its nutritional value, also make it useful in paint and explain its instability. Hempseed is high in polyunsaturated fatty acids, those having two or more double bonds between the carbons in the chain. These double bonds are unstable, tending to oxidize. From a nutritional point of view, this oxidation is rancidity.