Food Tests

Identifying Food Nutrients Carbohydrates Iodine Test: Cut a section of carbohydrate-rich food to expose the flesh. Pour drops of iodine on the exposed flesh. If it turns black or darkish brown, it indicates the presence of carbohydrates. If it remains light brown, carbohydrates are absent. Litmus Test: Peel and grate the food item, then make […]

Identifying Food Nutrients

Carbohydrates

  1. Iodine Test: Cut a section of carbohydrate-rich food to expose the flesh. Pour drops of iodine on the exposed flesh. If it turns black or darkish brown, it indicates the presence of carbohydrates. If it remains light brown, carbohydrates are absent.
  2. Litmus Test: Peel and grate the food item, then make it into a paste. Immerse red litmus paper into the paste. If it turns blue, it shows the presence of carbohydrates; if unchanged, it lacks carbohydrates.

Proteins

  1. Foam Test: Dissolve the food substance in water and shake vigorously. The production of foam indicates the presence of protein. The absence of foam suggests no protein.
  2. Alcohol Test: Immerse the food product or its solution in alcohol. Coagulation, shrinking, or curdling indicates the presence of protein. Meat may change colour to brown.
  3. Million’s Test: Warm the foodstuff with Million’s reagent. A white precipitate, turning red, confirms the presence of protein, except for gelatin.

Fats

Blotting Paper Test: Grind a small quantity of foodstuff between two pieces of blotting or filter paper. Translucency or greasiness on the paper indicates the presence of fats or oil. Absence of such indicates no fat.

 

Food Composition Table

A food composition table is a tabular representation of the nutritive value (nutrient amounts) of common food commodities, whether raw, processed, or cooked.

 

Purposes of a food composition table:

  1. Provides accurate information on the nutritive values of major food commodities, preventing consumer misinformation by food processors and marketers.
  2. Facilitates the comparison of food values to help consumers make informed choices according to their nutritional needs.
  3. Assists in meal planning tailored to specific groups, such as infants, adolescents, and the elderly.
  4. Enables the calculation of nutritional content for comparison with standards, determining if a food meets the Recommended Daily Allowance (RDA) for nutrients.

 

Factors affecting the food composition table:

  1. Nature and type of soil used to grow the commodity.
  2. Variety of plant or breed of animal.
  3. Age of the animal affecting meat and milk composition.
  4. Type of feed given to animal and poultry livestock impacting meat, milk, and egg composition.
  5. Climatic conditions during plant growth.
  6. Handling and storage methods.

Related Posts:

The Scientific Study of Food

Absorption

Digestive System

Dietary Deficiency

Mineral Elements | Macro Elements, Micro Elements & Water

Leave a Comment

Your email address will not be published. Required fields are marked *

Scroll to Top