Summer has arrived, and it’s time to fire up the backyard grill. Though many of us are trying to eat less beef for environmental reasons, it’s hard to resist indulging in an occasional steak — and you’ll want to make the most of the experience.So, what’s the best way to grill that steak? Science has some answers. Meat scientists (many of them, unsurprisingly, in Texas) have spent whole careers studying how to produce the tenderest, most flavorful beef possible. Much of what they’ve learned holds lessons only for cattle producers and processors, but a few of their findings can guide backyard grillmasters in their choice of meat and details of the grilling process.