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

scientificamerican.com

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

#91

Post by thinkloop »

sukilot wrote: post #85
spoofball wrote: post #69

Earlier quoted context omitted.

the majority of pet food is meat not fit for human consumption. [1] if you aren't feeding your pet meat that you eat, it's living on extreme crap. [1]: http://www.dogfoodadvisor.com/dog-food-industry-exposed/unfi...

People like fancy food. That doesn't make non-fancy food extreme crap.

"not fit for human consumption" is not a synonym for "unfancy". It describes the processes involved to arrive at the final food. Filet mignon can be unfit for human consumption, while pigs' feet can be processed correctly and be fit for consumption.

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

#92

Post by thinkloop »

Someone wrote: post #17
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 linked-to https://en.wikipedia.org/wiki/2008_Chinese_milk_scandal was way more scandalous. When bought in bulk, milk isn’t priced by the liter because it is too easy to water it down. Instead, it is priced by kilograms of protein. Measuring protein is hard, so they measure nitrogen instead ( https://en.wikipedia.org/wiki/Kjeldahl_method#Conversion_fac... , https://en.wikipedia.org/wiki/Dumas_method#Advantages_and…

They went hard on the justice atleast:

"Two people were executed, one given a suspended death penalty, three people receiving life imprisonment, two receiving 15-year jail terms,and seven local government officials, as well as the Director of the Administration of Quality Supervision, Inspection and Quarantine (AQSIQ), being fired or forced to resign"

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

#93

Post by mapt »

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.

How do you distinguish between evaporated water and respirated CO2?

As an aside: My understanding was that most breads don't vent all that much CO2. Bread doughs are not risen in processes that leave the opportunity for rapid bubble formation and dissolution; If they did, baking after that first rise would give you a layer of thick dense bread, and another layer of fluffy bubble-bread on top.

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

#94

Post by danieltillett »

spoofball wrote: post #72
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

Cows are not extracting protein from grass (well not much), they are converting the cellulose in the grass into microorganisms and then extracting the proteins from the microorganisms. The ruminant digestive system is an amazing system [1].

1. https://en.m.wikipedia.org/wiki/Ruminant

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

#95

Post by yodsanklai »

> The original method used to determine the number of kcals in a given food directly measured the energy it produced.The food was placed in a sealed container surrounded by water--an apparatus known as a bomb calorimeter. The food was completely burned and the resulting rise in water temperature was measured.

I don't think the article addresses the following point. I may be totally wrong but I suspect the residues of the combustion still contain organic molecules that could possibly be broken down furthermore by some other process and release more energy (I believe it's the case with fuel, I remember a chemistry teacher telling us that burning fuel was terribly inefficient).

Would it be possible that the digestion mechanism is somehow more efficient at breaking down this molecules and produce more energy than combustion?

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

#96

Post by vrc »

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 know some smaller brands estimate using the USDA Food Composition Database (https://ndb.nal.usda.gov/), which in turn gets its data under the National Food and Nutrient Analysis Program (http://www.ars.usda.gov/News/docs.htm?docid=9446).

This is what I could find about their data:

"Data have been compiled from published and unpublished sources. Published data sources include the scientific literature. Unpublished data include those obtained from the food industry, other government agencies, and research conducted under contracts initiated by USDA’s Agricultural Research Service (ARS)." (http://www.ars.usda.gov/sp2UserFiles/Place/80400525/Data/SR/... <- page 2)

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

#97

Post by thinkloop »

thinkloop wrote: post #91
sukilot wrote: post #85

Earlier quoted context omitted.

People like fancy food. That doesn't make non-fancy food extreme crap.

"not fit for human consumption" is not a synonym for "unfancy". It describes the processes involved to arrive at the final food. Filet mignon can be unfit for human consumption, while pigs' feet can be processed correctly and be fit for consumption.

Check this out: http://www.alive.com/health/fit-for-human-consumption/

Animals that are sick or unhealthy are separated from the herd and slaughtered independently, then sold for pet food and livestock feed. This was partly what fostered the mad cow issue.

There is higher risk for illness with non-human grade food. If you don't want higher risk for your pet than child, you shouldn't feed the off-the-shelf non-human grade food.

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

#98

Post by awqrre »

thesimon wrote: post #23
lukasm wrote: post #12

In Poland it's regulated, you can be off by 15%. My mate did tests in a lab. All products he picked showed 15% lower kcal value on the packaging. I pick reduced fat houmous from the fridge. The label says 100g has 256kcal (18g of fat, 13g of carbs, 8,5g of protein = 248kcal)

And apparently in the US you can be off by whatever you want https://www.youtube.com/watch?v=hE2lna5Wxuo The video also deals with calorie count in restaurants. The NYC regulation to require calorie counts directly on the menu really seems like a good idea. Other than the people already knowing the rough calorie count, who checks the obscure and difficult tables on the website?

The government doesn't even have the resources to check fish species that are sold in grocery stores and restaurants [1]... food labeling is a big problem in the US.

1. http://www.npr.org/sections/thesalt/2013/02/21/172589997/one...

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

#99

Post by lsc »

thinkloop wrote: post #97
thinkloop wrote: post #91

Earlier quoted context omitted.

"not fit for human consumption" is not a synonym for "unfancy". It describes the processes involved to arrive at the final food. Filet mignon can be unfit for human consumption, while pigs' feet can be processed correctly and be fit for consumption.

Check this out: http://www.alive.com/health/fit-for-human-consumption/ Animals that are sick or unhealthy are separated from the herd and slaughtered independently, then sold for pet food and livestock feed. This was partly what fostered the mad cow issue. There is higher risk for illness with non-human grade food. If you don't want higher risk for your pet than child, you shouldn't feed the off-the-shelf non-human g…

> if you care about your pet like you do your child, you shouldn't feed the off-the-shelf non-human grade food.

This is... an interesting generational thing, I think. To most older people, the idea of caring as much for your pet as you would for a child seems viscerally wrong. They even economize on pet healthcare. but... among those younger than me, your view, as far as I can tell, seems to be the norm. The very idea that you might be unwilling to go bankrupt paying for medical care for your pets seems abhorrent.

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

#100

Post by gambiting »

yodsanklai wrote: post #95

> The original method used to determine the number of kcals in a given food directly measured the energy it produced.The food was placed in a sealed container surrounded by water--an apparatus known as a bomb calorimeter. The food was completely burned and the resulting rise in water temperature was measured. I don't think the article addresses the following point. I may be totally wrong but I suspect the residues of…

Considering how nutritious(for bacteria) our faeces are, I strongly suspect not. If anything, we know that calories from certain types of food (like nuts) are not absorbed in 100%, so even though a packet of nuts might say it has 500 kcal, it doesn't mean you will get 500 kcal out of it.
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