Conclusions cannot be drawn from the direct comparison between the vitamin and mineral composition of different forms of a specific food (raw, boiled, frozen, canned, etc.). The destruction of some nutrients by heat is only one of the factors influencing nutrient composition during processing. Moisture loss during cooking leads to the concentration of all nutrients. In addition, most often it is not samples of food from the same crop that were analysed raw, frozen, boiled, canned or dried. Differences in growing conditions, sample handling, etc. could therefore result in nutrient differences. Analyses for the various forms (raw, boiled, frozen, canned, etc.) of a food item may also have been done at different analytical laboratories, possibly using different analytical methodologies and thus producing different values. With inter-laboratory studies the impact on values, using different analytical methods, can be minimised. Adding additional ingredients to processed food as well as the fortification of the food item may also influence the final analytical values.