[m0rose]

Since we're being blunt: This is misleading.

We don't use the bomb calorimeter today, but we still use the Atwater system (with a quick tweak for fiber) for those "nutritional components." All that means is instead of burning the food ourselves we're looking at a table that the guy who burned the foods created... with his bomb calorimeter.[1] The only reason we're marginally better now is because we're starting to take into account digestibility (e.g. Carbs have non-digestible fiber subtracted before the calories are calculated).[2]

[1]https://www.scientificamerican.com/article/how-do-food-manuf...

[2]https://en.wikipedia.org/wiki/Atwater_system#Modified_system

[dtech]

So you're repeating the exact point I was making. A bomb calorimeter is not used anymore today. Altough it is very interesting that the 4 kcal/g protein etc values are still used based on that research, I thought the values had been better determined nowadays. At least progress is possible and being made.

But still, what the gp says was that a wooden log would have a food label with a high calorie content. That is not correct.

[nkurz]

But still, what the gp says was that a wooden log would have a food label with a high calorie content. That is not correct.

Was the original comment edited? As it reads now, the GP makes no mention of a label, only the factually correct statement that a log "is several megacalories" (ie, hardwood releases about 20 kCal/g when burned) but "you'll starve eating it" (ie, human digestion is not able to make use of this energy).

You are right that a current nutritional label would not show the log has having any significant number of calories, but the GP's actual post never said that it would. What makes you visualize this non-existent food label and then claim it is incorrect, as opposed to accepting their statement as written?

[dtech]

The article is about how "the calorie is dead" (title), in the context of human consumption. The GP says "makes sense, a log of wood is several megacalories but you'll starve eating it". My point is that a log would have a food label with very little calories, not several megacalories. It does not "make sense" to use as support for "the calorie is dead".

[xkcd-sucks]

Exactly, energy that one can't use,and do they like do a chromatographic separation before calorimetry or what??

I also do wonder about the calories in ethanol. Apparently its immediate metabolism does produce a few atp, but the fact that hangover cures are universally high calorie foods suggests that the downstream steps might be endothermic or rate limited by fat, if that's even possible