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How do food manufacturers calculate the calorie count of packaged foods? (2003)

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Re: How do food manufacturers calculate the calorie count of packaged foods? (2003)

#71

Post by misinformation »

chris_va wrote: post #46
misinformation wrote: post #26

Earlier quoted context omitted.

Bit different answer: Yes it is possible. While it is true that two individuals eating the same food will gain weight differently, if you count your calories and measure everything you'll eventually learn (In the body building community we usually say two weeks) how many calories you need to keep your weight. With that information, you can adjust your calorie intake to lose weight. Say your maintenance is 2500 calori…

That is not entirely true (not entirely false either), the reality is more complicated. Your metabolism level, and the percentage of calories that are actually taken up by fat cells, depend on many factors besides total calorie count. A nice paper that came out recently: https://www.sciencedaily.com/releases/2015/11/151119143445.h... So, for example, person A can eat 3000 calories of cookies per day, but would gain w…

The question I responded to was along the lines of "Can calorie count reliably predict the effect on a person's weight?". Now my conclusion is that your answer that "The short answer is "no"" is wrong.

I don't see what fat cells have anything to do with this either.

As for your rebuttal of my points, it does not seem sequent. I made the point that two individuals eating the same food will gain weight differently. You then made the very same point by linking to another paper which by the way does not support what either of us said - as it measured individuals individual glycemic responses to different foods, which is not correlated with the body's calorie intake on the food.

Here's the full paper in case you did not read it (and for others to read if they'd like): http://www.sciencedirect.com.sci-hub.cc/science/article/pii/...

As for the paper, the graphics used represent outliers. Plus they in one example compared cookies and bananas. Both which have different metabolic pathways. Fructose is handled in the liver and glucose is not. When they compared bread and glucose the difference was not quite as drastic even when comparing outliers. Therefore it seems more like it has to do with varying ability in people's bodies efficiency to metabolise fructose and glucose.

Re: How do food manufacturers calculate the calorie count of packaged foods? (2003)

#72

Post by spoofball »

tezza wrote: post #27

> 9 Kcal/g for fat. [...] These numbers were originally determined by burning This method for calculating the calorie count for fat has in my opinion allowed the demonisation of fat. Our stomachs are imperfect at digesting globules of fat. Burning-until-gone releases much more of the energy than surface acting acids and proteinases. Effective calorie count for fat just has to be so much lower than the listed value. C…

same thing is for protein present in grass but indigestible for humans.

cows can extract "enormous" amounts of protein from foods that humans wouldn't ever.

it's very hard measuring how much digestible protein something has, such as beans, or lentils, or soybeans. it depends if you eat the shell, did you blend the shell like a mad man, even if you blended beans into a homogenous phlegm

Re: How do food manufacturers calculate the calorie count of packaged foods? (2003)

#73

Post by silviogutierrez »

maxerickson wrote: post #34
silviogutierrez wrote: post #3

There are foods on which the standard processes don't accurately measure energy content. Or at least, certain manufacturers tell us that. Not sure if to believe them or not. Example: Quest bars. Their syrup would typically show 4 kcal per gram, but is actually closer to 2. Supposedly. That's how a bar can have so few calories and such good macros. Ultimately, if you're consistent with tracking your calories and its e…

I'm not sure what the syrup in those bars would be, but most liquid sugar products have a pretty substantial portion of water by mass.

The original syrup was https://en.wikipedia.org/wiki/Isomaltooligosaccharide . I buy retail for my own recipes, under the brand name VitaFiber.

Re: How do food manufacturers calculate the calorie count of packaged foods? (2003)

#74

Post by spoofball »

qq66 wrote: post #51

This reminded me of a question I've always had... there's always a lot of mass of the food not accounted for in the Fat/Carbohydrates/Protein/Fiber. For example, a can of food that weighs 454g net might only have 150g accounted for in the nutrition facts. What's in the rest of the food, besides water?

usda when measuring cooked or raw beans, for example, measures them differently.

for example cooking 100g of beans in 500g of water would result in, let's say, 450g of beanwater (beans + water). usda takes 100g of that beanwater and says it's 100g of cooked beans (water content of cooked beans is way higher than in raw beans [their tables say]).

I was worried there's not enough protein in 100g of cooked beans, but there is, it's just not 100g of cooked beans, it's 450g of beanwater.

Re: How do food manufacturers calculate the calorie count of packaged foods? (2003)

#75

Post by lostlogin »

cma wrote: post #4
alexbock wrote: post #2

The obvious next question then is how the protein and carbohydrate content is measured. That sounds like it would require more difficult analytical methods than bomb calorimetry and might not be worth the time and expense if it were not for the fact that those need to be reported separately on the label anyway. Brief searching suggests that proteins are measured with a nitrogen content test and fats are determined by…

The protein test was famously faked with melamine in the Chinese dog-food scandal that killed dogs and resulted in a recall: https://en.wikipedia.org/wiki/2007_pet_food_recalls

The same cheat was used in milk in China in '08. Baby formula was effected and babies died. Many companies were doing it and something like 50,000 babies were hospitalised. https://en.m.wikipedia.org/wiki/2008_Chinese_milk_scandal

Re: How do food manufacturers calculate the calorie count of packaged foods? (2003)

#76

Post by fcoury »

alexbock wrote: post #2

The obvious next question then is how the protein and carbohydrate content is measured. That sounds like it would require more difficult analytical methods than bomb calorimetry and might not be worth the time and expense if it were not for the fact that those need to be reported separately on the label anyway. Brief searching suggests that proteins are measured with a nitrogen content test and fats are determined by…

I found this URL that explains different methods of carbohydrate analysis in food: http://people.umass.edu/~mcclemen/581Carbohydrates.html

Re: How do food manufacturers calculate the calorie count of packaged foods? (2003)

#77

Post by z3t4 »

lostlogin wrote: post #75
cma wrote: post #4

Earlier quoted context omitted.

The protein test was famously faked with melamine in the Chinese dog-food scandal that killed dogs and resulted in a recall: https://en.wikipedia.org/wiki/2007_pet_food_recalls

The same cheat was used in milk in China in '08. Baby formula was effected and babies died. Many companies were doing it and something like 50,000 babies were hospitalised. https://en.m.wikipedia.org/wiki/2008_Chinese_milk_scandal

Considering how cheap protein is, you must be the greediest person ever to fake baby formula.

Re: How do food manufacturers calculate the calorie count of packaged foods? (2003)

#78

Post by anarazel »

jobigoud wrote: post #66
ng12 wrote: post #25

Earlier quoted context omitted.

But they also list servings per package. As someone who relies on this information out of medical necessity I've never felt it to be that confusing. The EU/UK, on the other hand, makes it incredibly difficult by listing things in units of 100g. Nothing like sitting in a dark movie theater trying to calculate fractions.

I often find it more convenient actually because often you don't eat "one serving". Consider breakfast cereals, rice or pastas. Having the per 100g values allows you to actually compare one item to the next. When I'm the US I find myself trying to convert back the per serving to per 100g to get back to known territory.

This.

Not even primarily due to health/nutritional concerns. A lot of the cereals in the US are way to sweet for my taste. Haven't found a better way to figure out which isn't other than comparing contained sugar.

Re: How do food manufacturers calculate the calorie count of packaged foods? (2003)

#79

Post by jasonjei »

snewk wrote: post #59
jasonjei wrote: post #40

Earlier quoted context omitted.

Agreed. 500 calories from chicken or a lean protein like crab is very different from 500 calories from a pastry. What should be highlighted is amount of sugar and carbohydrates, not total calories. Not every calorie is created equally. In fact, you could almost remove carbohydrates from your diet and be unaffected, but the same isn't true of protein and good fats.

i don't understand why your comment scores so low. It's pretty clear that our bodies will absorb 500 sugar/carbohydrate calories much more quickly than 500 protein/fat calories. You will get a much greater insulin response when eating a pastry than a chicken breast.

I suspect I'm being down voted because I said I don't believe carbohydrates are required for survival.

While glucose is essential for life since the brain cells die quickly without it, glucose does not have to be obtained from carbohydrates. It can be obtained from protein or fat by breaking down the protein or fat into glucose. In fact, a good percentage of protein (~50%) becomes glucose when it enters the body.

Protein is favored over many other energy forms since it contains amino acids, one of the most useful sources of nutrients to your body. Your body cannot store amino acids and yet it needs a daily intake of amino acids to survive. Additionally, protein conversion to fats is costly, so your body under normal conditions does not usually convert much of it, compared to fats and carbohydrates (carbs almost immediately undergo storage). Good fats, however, are beneficial (essential even for health) than carbohydrates in all cases.

Or perhaps someone might enlighten me why I'm wrong (at the time of this writing, my original comment has 0 points of karma).

I've cut bread and processed sugar to a large degree from my diet and stick to lean proteins like seafood and chicken, and have found myself to be quite lean and healthy (bulking even with my anterior/posterior chain, triceps/biceps). I haven't counted calories since I switched to a diet that focuses on lean protein and seafood (and I suspect there are days where I eat more than 2000 kCal).

Re: How do food manufacturers calculate the calorie count of packaged foods? (2003)

#80

Post by Symbiote »

analog31 wrote: post #62
alexbock wrote: post #11

Earlier quoted context omitted.

If anyone can find a reference on the amount of CO2 produced during bread making it would be easy enough to calculate. I haven't been able to find any relevant sources except this old one [1] which mentions that the alcohol content in bread can be as high as 1.9 percent (which sounds quite high to me, but it's hard to critique when they don't explain their methodology). [1] http://www.ncbi.nlm.nih.gov/pmc/articles/PM…

Well, all I can offer is... tonight is baking night. I will weigh the ingredients, equipment, the risen dough, and the final product.

You could also seal the dough in a large bag, and measure the volume of gas produced.
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