FOOD 2010 Chapter Notes - Chapter 5: Food Composition Data, Spectrophotometry, Calorie

• School: University of Guelph
• Department: Food Science
• Course: FOOD 2010
• Professor: Massimo Marcone

Document Summary

Composition of foods is determined by a variety of scientifically sound, standardized methods. The first system of approximating the nutritional value of a food was developed at the weende. Experiment station more than 100 years ago (in germany)- this system separates a food into nutritive fractions through a series of chemical determinations: the different fractions included water or dry matter, crude protein, ether extract (crude fat), Proximate analysis sugars and starches (nitrogen-free extract) and ash or total mineral. A newer methods spectrophotometry, and liquid and gas chromatography- they allow the determination of fatty acids, cholesterol, amino acids and specific minerals and vitamins. Energy is measured in terms of calories. Calorie is a metric unit of heat measurement the small calorie (cal) is the amount of heat required to raise the temperature of 1 gram of water from 14. 5 degrees to 15. 5 degrees celcius.