In his new commentary on Genesis, Bill Arnold has an interesting interpretation of the dietary laws in the Noahic covenant, which he evidently borrows from Edwin Firmage:
“However, the new order is not altogether the same as the old, since it also involves an alteration of the food chain (9:3). Many readers assume this text implies something inherently virtuous in vegetarianism, since it was the original cosmic order (“plan A”), or inversely, something innately blameworthy in meat-eating. Others have assumed the change in human diet is a concession to humanity’s weakness. But in reality, the only implication of the text is that the new order is also accompanied by a change in the animals’ relationship to humans (9:2). The fear of humanity is new, since pre-flood animals enjoyed a primitive fellowship with humans, now lost in the new natural order of things. Rather than placing value on either vegetarianism or meat-eating, this supplement of Noah’s diet with meat is part of a biblical progression toward holiness for humanity. By incremental steps, the biblical dietary laws bring humans from vegetarianism, to unrestricted meat-eating, and finally, to a dietary law that distinguishes Israelites from their neighbors (Lev 11). ‘[T]he dietary law represented the culmination of a progression in holiness, by which God had brought a people by steps to enjoy unprecedented proximity to himself’” Genesis (Cambridge 2009), 109.