Is it more cost-effective to buy leaner ground beef?

Plenty of times, as I drain unseemly amounts of grease from ground beef (we generally buy either 73/27 or 80/20), I’ve wondered whether it is really cheaper to buy the cheap stuff or not. By pouring off 27% or more, am I dumping my savings? So I decided to put it to the test.

Raw weight: 73% ground beef - 12.7oz; 93% ground beef - 16.2oz
Raw weight:
73% ground beef – 12.7oz
93% ground beef – 16.2oz

ground beef patties cooking, 73% on left, 93% on rightI started with two packages of ground beef, the cheapest, nastiest 73/27 available ($2.196/lb) and some 93% lean ($4.436/lb). I formed them into patties and—once I finally was able to wash the slime from the 73% off my hands—cooked them in separate skillets. I cooked them identically—if I covered one, I covered them both; if I turned the burner down on one, I turned it down for both.
When they were done cooking, it was time to weight again.

Cooked weight: 73% ground beef - 6.8oz; 93% ground beef - 13.3oz
Cooked weight:
73% ground beef – 6.8oz
93% ground beef – 13.3oz

The 73% weighed in at 53.5% of its raw weight, while the 93% retained 82.1% of its original weight. So the actual post-cooking price per pound is $4.10 for 73% and $5.40 for 93%. Sigh….looks like it’s still more cost-effective to buy the fattier meat and throw away the fat.

the drained grease, 73% - 1/2 cup, 93% - not measurable
Ewwww

But, of course, these prices aren’t constant. So, using my rusty algebra skillz, I determined that if the pre-cooked price per pound of the 93% lean is less than 53.4% more than the price of the 73%, it is more cost-effective to buy the 73%. In the grocery store, then, just divide the cost of the 93% by the cost of the 73%. If the answer is more than 1.534, buy the 93%; if less, buy the 73%.

Of course, if you just can’t stand the sight of 1/2 cup of fat, buy the leaner meat. Which I totally get.