Riverside College - Physiologic Value of Food

Riverside College Overview

• Riverside College is located in Bacolod City, Philippines, and was established in 1954.
• It is affiliated with Metro Pacific Health.

Physiologic Value of Food

• Food is composed of various compounds, both organic and inorganic.
  • Organic Compounds: Includes proteins, lipids, carbohydrates, vitamins, water.
  • Inorganic Elements: Includes carbon, hydrogen, nitrogen, etc.

Chemical Structure of Food Substances

• Proteins, Lipids, Carbohydrates:
  • These are essential macronutrients for the body.
• Organic Compounds:
  • Substances that contain covalently bonded carbon, hydrogen, and other elements.
  • Can consist of simple molecules, typically with one or two different elements.

Energy Measurement in Nutrition

• Calorie:
  • The standard unit for measuring energy from food, commonly expressed as kilocalories (kcal).
  • 1 kcal = 1000 calories.
• Bomb Calorimeter:
  • Device used to measure the total calorie content in food.
• Energy is measured in joules:
  • 1 kcal = 4184 joules (4.184 kJ).
  • Example: 1 cup of milk contains 170 kcal, which translates to 711.28 kJ.

Energy Calculation from Macronutrients

• Fuel Factors:
  • Carbohydrates: 4 Calories per gram.
  • Protein: 4 Calories per gram.
  • Fat: 9 Calories per gram.
• Example Calculation for 1 cup of milk:
  • 12 g Carbohydrates x 4 kcal/g = 48 kcal
  • 8 g Proteins x 4 kcal/g = 32 kcal
  • 10 g Fat x 9 kcal/g = 90 kcal
  • Total: 48 kcal + 32 kcal + 90 kcal = 170 kcal.

Calculation of Physiologic Food Value

• For given quantities: 1 1/2 cups of whole cow’s milk and 2 teaspoons of muscovado:
  1. Nutrient Content:
  • Whole Cow’s Milk:
    • Carbohydrates: 12 g
    • Proteins: 8 g
    • Fats: 10 g
    • Energy: 170 kcal
  • Muscovado:
    • Carbohydrates: 5 g per teaspoon,
    • Energy: 20 kcal (for 1 tsp).
  1. Total Weights and Energy:
  • Total Weight = 18 g (carbohydrates) + 12 g (proteins) + 15 g (fat) = 55 g.
  • Total Energy = 72 kcal (CHO) + 40 kcal (protein) + 48 kcal (fats) + 135 kcal (from muscovado) = 295 kcal.
  1. Nutrient Percentages calculated based on total grams and total energy:
  • Carbohydrates = 28 g, Protein = 12 g, Fat = 15 g; Total = 295 kcal.

Example of Percent Energy Contribution

• Carbohydrate Percentage:
  • (112 kcal from CHO) / 295 kcal = 0.3797 = 37.97%
• Protein Percentage:
  • (48 kcal from protein) / 295 kcal = 0.1627 = 16.27%
• Fat Percentage:
  • (135 kcal from fats) / 295 kcal = 0.4576 = 45.76%

Summary Table of Nutrients and Energy