To find out, we sent samples, raw and grilled, to the lab for analysis. From the raw samples, we wanted to know if the fat-ratio labels were even accurate. The answer there was "sort of." All grinds had slightly less fat than labeled; our 90/10 was actually 93/7. From the grilled samples, we wanted to know: How much gets lost over a fire? See answers below.
80/20 fattiest grind Raw (4 ounces): 21.2g total fat, 9g sat fat Grilled (2.6 ounces): 14.2g total fat, 6.1g sat fat Shrinkage: 34% weight loss, 33% fat loss
This grade indeed lost the most fat, but the resulting burger was still left with almost double the fat of the leanest grind.
85/15 Raw (4 ounces): 16.8g total fat, 6.9g sat fat Grilled (2.7 ounces): 12.4g total fat, 5.1g sat fat Shrinkage: 33% weight loss (wow!), 26% fat loss
90/10 leanest grind Raw (4 ounces): 8.3g total fat, 3.5g sat fat Grilled (3.1 ounces): 7.5g total fat, 3.2g sat fat Shrinkage: 22% weight loss, 10% fat loss
* Still our recommended grade—just as tasty but with much less fat. Less shrinkage, too.What the Ratios Mean: The ratio is percentage by weight. Fat is higher in calories than protein, so a 4-ounce raw 80/20 beef patty has 285 calories, versus a 90/10 patty, which has 200 calories. And the 90/10 has 12.9 fewer grams of total fat.
Photo: Francesco Tonelli/Philippa Brathwaite