ABSTRACT
Foods are often characterized by the composition of their chemical components. However, a wide range in the precise levels of those constituents may in fact exist, due to intrinsic biological variability, multiplicity of cultivars and variants of each species, or as a result of geographical location, environmental and seasonal influences, or from the application of genetic engineering. Furthermore, the chemical composition of foods may also be influenced by natural or unintentional contaminants, by processing or upon storage. This potentially wide range of composition and characteristics leads to difficulty in defining the chemical composition of foods, and to issues of validating authenticity or detecting adulteration issues (1).
