FDSC 200 Lecture 12: 12_Energy Content of Food

• School: McGill University
• Department: Food Science
• Course: FDSC 200
• Professor: Lawrence Goodridge

Document Summary

Provide fuel & raw material for growth (young) & maintenance (mature) 1 calorie = amount of heat required to increase the temperature of 1g h2o by 1oc: measured from 14. 5 to 15. 5oc. 1 cal = 4. 184 j: food calories (cal) the calorie (cal) is too small of a unit to measure energy in food. Determining energy content of food: bomb calorimeter is unreliable does not take into account digestibility, combustion of 1g cellulose produces the same amount of heat as combustion of 1g starch. *by definition, fiber is indigestible carbohydrate: energy content is derived from organic acids produced by microbial fermentation of such carbohydrates in the intestinal tract: fats, very high calorie. much higher number of carbon atoms per gram: combustion to co2 involves reaction with a larger number of o2 molecules, 9kcal/g is the average value. Longer fatty acid chains higher caloric content: compact way to store energy.