digging. Perennial rhizomes are left in the ground for propagating the next crop, or, alternatively, they can be kept in a refrigerator or buried away from freezing temperatures until spring. Chemistry The chemical composition of yacon varies depending on factors such as location, farming, the growing season, harvest time and the post-harvest temperature. Yacon tubers consist mostly of water and carbohydrates. The water content is about 70% of fresh weight. Therefore, the energy value is low. The dry matter is composed of out of 40-70% of fructooligosaccharides. Inulin, a low-polymerization β(2-1)-oligosaccharide is the main fructooligosaccharide in yacon. These oligosaccharides are known to be nontoxic, non-digestible and sweet. There are also 15-40% simple sugars as sucrose, fructose and glucose. The most abundant minerals in yacon are calcium and potassium. In addition, yacon juice is rich in free essential amino acids. Dry basis ND Not determined Carbohydrate was estimated by the difference FOS Fructooligosaccharides ND Not determined Special compounds Yacon tubers are rich in bioactive compounds, which occur naturally in both the leaves and the roots. Most of the beneficial effects reported from consumption of this tuberous plant result from the presence of such compounds. The major antioxidative compounds in yacon are chlorogenic acid and L-tryptophan. Yacon contains also different phenolic compounds. The phenolic compounds enable epiphytic bacterial growth with very specific metabolic properties, inhibiting the attack of pathogens. Polyphenols found in yacon leaves and bark produce an acrid and astringent flavour, as well as impart a typical odour. Polyphenols are also substrates for the enzymatic browning of damaged tissues in yacon root, giving it a greenish or black colour due to a condensation reaction of polyphenol compounds with amino acids and the enzymatic polymerization of polyphenols. Use Generally, yacón is cultivated in different countries for food and medicinal use. Since 1960, this plant spread from South America to a lot of different countries around the world such as New Zealand, Japan and many other countries which lead to variable usages. Food and storage The tubers can be eaten raw, boiled, dehydrated, roasted or processed into beverages, jams, syrup, vinegar, flour, chips and juice. If they are eaten fresh, they are sweet and crunchy. While usable-sized edible tubers develop fairly early in the season, they taste much sweeter after they have matured and have been exposed to some frost. After harvest tubers left in the sun to harden taste much better than