this is just my understanding..
Equities are a good inflation hedge, especially when firms can pass inflation on to the consumer
Similarly, if a commodity is storable, the producer can pass the inflation to its customers by waiting until he gets a right price (the commodity wont be wasted away by waiting…)
however, a non-storable commodity producer cannot do that..he has to sell to what ever the price he gets…
basically it depends on the Price elasticity of demand…
again, this is just my understanding..not sure if this is exactly the case…