Energy conversion factors The Atwater general factor system includes energy values of 4 kcal per gram (kcal/g) (17 kJ/g) for protein, 4 kcal/g for carbohydrates and 9 kcal/g (37 kJ/g) for fat. Alcohol is also technically considered a macronutrient and contains 7 kcal/g (29 kJ/g).
What is the Atwater equation?
Calculated with modified Atwater equation (AAFCO, 1997): ME (kcal/kg) = 10 × (3.5 × Crude Protein % + 8.5 × Crude Fat % + 3.5 × Nitrogen-Free Extract %).
What are the Atwater general factors?
The Atwater general factor system includes energy values of 4 kcal per gram (kcal/g) (17 kJ/g) for protein, 4 kcal/g for carbohydrates and 9 kcal/g (37 kJ/g) for fat. Alcohol is also technically considered a macronutrient and contains 7 kcal/g (29 kJ/g).
What is the Atwater scale?
The Atwater system, named after Wilbur Olin Atwater, or derivatives of this system are used for the calculation of the available energy of foods. As with the calculation of protein from total nitrogen, the Atwater system is a convention and its limitations can be seen in its derivation.
Are Atwater factors accurate?
Although modified Atwater factors may be accurate under standardized conditions of zero-nitrogen and zero-energy balance, they overestimate energy availability from high-fiber fruit and vegetable and cereal diets when food intake is reduced spontaneously in addition to when intake is reduced voluntarily.
Are Atwater factors gross energy?
The Atwater factors have important shortcomings. The gross energy contents of dietary proteins, fats, and carbohydrates are not constants. Other chemical components in foods other than protein, fat, and available carbohydrates contribute energy and may influence the ME of the principal chemical components.
How does the Atwater system work?
The Atwater system uses the average values of 4 Kcal/g for protein, 4 Kcal/g for carbohydrate, and 9 Kcal/g for fat. Alcohol is calculated at 7 Kcal/g. (These numbers were originally determined by burning and then averaging.)
What is Atwater?
Atwater is a city on State Route 99 in Merced County, California, United States. Atwater is 8 miles (13 km) west-northwest of Merced, at an elevation of 151 feet (46 m). The population as of the 2010 census was 28,168.
What is Atwater indirect system?
Today, producers use the “Atwater indirect system” to calculate calories by adding up the calories provided by the energy-containing nutrients: protein, carbohydrate, fat and alcohol.
Is the Atwater system accurate?
How do I calculate nutritional information?
Make a list of all the ingredients in your product. Write down how much of each is in there. Look up the nutritional values of each ingredients per gram of ingredient. Now multiply the amount of material with the nutritional values and you’ve got your values!
What is modified Atwater?
As such, AAFCO recommends the use of the modified Atwater equation [ME = 3.5×CP (%) + 3.5×N-free extract (NFE, %) + 8.5×crude fat (%)] to predict metabolizable energy (ME) of dog and cat foods, which is then used to calculate daily feeding allotment.
What is the Atwater factor of food?
Quick Reference. The Atwater factor is the energy value per unit mass of food expressed as kilo-calories per gram.
What are the variables in Atwater’s system?
The protein, fat and carbohydrate, alcohol contents are the variables, while the energy factors for the same compounds generally are treated as constants. However, in Atwater’s system there are eight variables on the right side of the equality sign as all the factors are variables.
What is the standard Atwater factor for fat?
The standard Atwater factor of 9.0 kilocalories (37.7 kJ) per gram of fat should be used for calculating the energy value of fat in all nutrition surveys and food composition tables; Standard methods and reference materials should be used in the analysis of the fatty acid content of foods and in the preparation of nutrient databases;
What is the Atwater conversion chart?
The Atwater Conversion Chart provides the calories per gram values for a wide variety of foods. Atwater Conversion Factors CompareArticlesHistoryVersionsDemoPDFsContactUpdateWhy Buy? PricesBuyOn-Line HelpMore
