An assortment of foods plays a vital role in maintaining the normal function of the human body by providing adequate and necessary nutrients. The single composite approach has given way to the concept that overall protection against disease is provided by a range of phytonutrients contained in foods. Scientists have identified thousands of different phytonutrients, found in vegetables, fruits, beans, whole grains, nuts and seeds. The wide application of phytonutrients indicates that nutrition science has advanced beyond the treatment of deficiency syndromes to reduce disease risk. Among the phytochemicals, carotenoids have been the widely studied ones. Glucosinolates are sulphur-containing glucosides prevalent in the cruciferous family of vegetables, especially Brassicas and are also present at relatively high levels in oilseeds and also in condiments. Allium compounds are organosulphur compounds found in Allium vegetables such as garlic, onions, shallots, scallions, chives and leeks, which are responsible for their distinctive flavour and aroma.