PDA

View Full Version : How do they test for Nutrition Facts?



Bignbuff
07-30-2009, 11:46 AM
Anyone know?

I've always wondered how they know that a serving of large french fries from McDonald's has 500 calories, 25g fat, 63g carb, 350mg sodium, 6g protein, etc.? Or a Taco Bell hard shell taco has 170 calories and 10g fat, etc.

I know they hire outside vendors to do the testing for them, but what exactly does the testing entail that allows them to make these claims.

papasmurf2217
07-30-2009, 11:49 AM
I'm pretty sure McDonald's or Taco Bell has to submit a list of all of the ingredients that go into making each patty, bun, taco shell, etc.

Obviously it's not going to be perfectly accurate because of how they're assembled at the restaurant (i.e. # of fries in a medium) but it's a good estimate.

nano.ix
07-30-2009, 11:50 AM
I've done soil testing and i would assume they undergo the same process'. Alot of chemical analysis to determine the chemical make up of the product/sample

http://www.sciencecompany.com/sci-exper/food_chemistry.htm
http://www.geocities.com/CapeCanaveral/Hall/1410/lab-B-09.html

More:

http://www.omafra.gov.on.ca/english/livestock/swine/facts/03-007.htm
http://www.scienceteacherprogram.org/biology/Lillien02.html

Bignbuff
07-30-2009, 11:52 AM
I'm pretty sure McDonald's or Taco Bell has to submit a list of all of the ingredients that go into making each patty, bun, taco shell, etc.

Obviously it's not going to be perfectly accurate because of how they're assembled at the restaurant (i.e. # of fries in a medium) but it's a good estimate.
Thanks. I figured that part, but I was more referring to how they test in general (i.e. how they test all the ingredients).


Chemical testing

these should explain how some are done. These are simplified versions but i think the lab testing is conducted in the same matter. Or relvativly close

http://www.sciencecompany.com/sci-ex..._chemistry.htm
http://www.geocities.com/CapeCanaver.../lab-B-09.html
Great reads .Thanks!

nano.ix
07-30-2009, 11:55 AM
Thanks. I figured that part, but I was more referring to how they test in general (i.e. how they test all the ingredients).


Great reads .Thanks!

edited for sence-ability :p

PremierGirl
07-30-2009, 12:28 PM
my answer is not completely supported I dont think but someone told me and so i always thought.... actually I think it was my H-chem teacher last year that since calories is like a measure of energy they run it through some sort of test and calculate the output energy....



lol i dont know the exact explanation she gave.


im curious how they get macros and all that though ... really interesting.

nano.ix
07-30-2009, 12:31 PM
my answer is not completely supported I dont think but someone told me and so i always thought.... actually I think it was my H-chem teacher last year that since calories is like a measure of energy they run it through some sort of test and calculate the output energy....



lol i dont know the exact explanation she gave.


im curious how they get macros and all that though ... really interesting.

calorimetry bombs ... not as exciting as they sound

FunkDaddy
07-30-2009, 12:44 PM
Don't you ever watch the Simpsons? Remember when Homer had to go back to school and the chemistry teacher started burning donuts to show how much fat was in it lol

ptflyforatallguy
07-30-2009, 01:25 PM
Anyone know?

I've always wondered how they know that a serving of large french fries from McDonald's has 500 calories, 25g fat, 63g carb, 350mg sodium, 6g protein, etc.? Or a Taco Bell hard shell taco has 170 calories and 10g fat, etc.

I know they hire outside vendors to do the testing for them, but what exactly does the testing entail that allows them to make these claims.

Gas-liquid chromatography to differintiate between the present compounds and fire (i.e. registering the thermal exchange of the compounds at there flash point to determine calories/joules and this is a very old technique developed in the 1930's and is a large topic of debate as to how they really translate into human use because we don't "BURN" calories).

lewistk
07-30-2009, 01:35 PM
Anyone know?

I've always wondered how they know that a serving of large french fries from McDonald's has 500 calories, 25g fat, 63g carb, 350mg sodium, 6g protein, etc.? Or a Taco Bell hard shell taco has 170 calories and 10g fat, etc.

I know they hire outside vendors to do the testing for them, but what exactly does the testing entail that allows them to make these claims.

bomb calirometer...i think the differnt nutrients give off different temperatures or something within the machine, thus allowing you to determine the macronutrients by temp?

nano.ix
07-30-2009, 01:50 PM
bomb calirometer...i think the differnt nutrients give off different temperatures or something within the machine, thus allowing you to determine the macronutrients by temp?

not quite. the CB works by incinderating the sample... without getting into details...

with that change in temperature, you can determine how many calories were in the sample (amount required to breakdown sample).
after that test, you will be left with only inorganic materials (for food ... there should be none)

... CB only measures exchange of heat. Other experiments must be conducted for chemical compounds

*food for thought (heh lulz) this is also how one can determine if a product can be used for biofuel.