Is the nutrient content always the same within the same type of food, for instance an apple?
In vegetable foods (fruits and vegetables), the content of nutrients will vary greatly according to type, growing conditions and degree of ripeness while harvested and used.
Conditions during storage, transport, industrial processing and/or preparation in household are also of importance for the nutrient content in foods, products and dishes. In addition, there is always some variation in analytical results from a laboratory.
The nutrient content in foods of animal origin primarily varies with the breed of the bird or animal, feed and the age at which they were slaughtered. The content in fish and shellfish also varies according to where and at what time of the year they werecaught or gathered and what they have been eating.
Many of the food items in the Food Composition Table are generic.For some fruits and vegetables there are values for both products cultivated in Norway and imported products.