Yacon

Sweet-root, Peruvian ground apple, strawberry jicama, Bolivian sunroot, llacon, ground pear, Chicama, Ilagon, and Yacon Strawberry.

Smallanthus sonchifolius (formerly Polymnia sonchifolia), synonymous with Polymnia edulis

Yacon is native to Colombia and Ecuador and is a hardy, attractive herbaceous perennial that has a very high yield of sweet tubers. As a member of the sunflower family, yacon can grow to 2 metres in height with small, daisy-like yellow to orange flowers.

Edible Uses

The stems and leaves of the yacon plant are cooked and eaten as vegetables. The tubers are textured somewhere between a potato and a crisp apple, and the flavour somewhere between apple and watermelon, with tones of sugarcane and maybe pear. We prefer to eat yacon raw. First remove the outer brown skin and inner white skin by peeling with a knife as the skin has a resinous taste, to reveal the amber coloured sweet crunchy flesh. They can be added to green salads, and they will absorb flavours from any herbs in the salad, such as coriander, fennel, etc. It can also be used in potato salad and Waldorf salads. When cut into long strips, they make an interesting addition to a plate of raw vegetable crudites for dipping into your favourite guacamole or cream cheese dip. In Peru, they are even made into candies. The sweet tubers are a food product that can serve as a sweet and refreshing treat that diabetics can enjoy without fear of increasing their blood sugar levels, and as a filling yet low caloric food that can help dieters lose weight by sating their appetite. Children living in the Andes have considered raw yacon a "special treat" for centuries, and because of its clean, crunchy, refreshingly sweet flavor, yacon can be a "special", yet healthy treat for anyone. Nutritionally yacon is low in calories but it is said to be high in potassium.

When first harvested, the root can taste somewhat starchy, but when allowed to mature for a few days in a dry place in the sun becomes sweet, crisp and juicy and is delicious eaten raw. The tubers can be eaten like a fruit or diced and added to salads. The skin has a somewhat resinous taste so it is usually removed. It can also be boiled, steamed or baked with other vegies. In cooking they stay sweet and slightly crisp. If boiled “in the jacket” the skin separates from the flesh and can be peeled off like a boiled egg. Yacon can also be used in a dessert crumble or pie with apples, pears or choko. The tubers juice well in an electric juicer and can be used to sweeten other juices or used in juice combinations. In the Andes, they are grated and squeezed through a cloth to yield a sweet refreshing drink. The juice can also be boiled down to produce a syrup. In South America the juice is concentrated to form dark brown blocks of sugar called chancaca. Leaves and stems - cooked as a vegetable. They contain 11 - 17% protein, dry weight. The sugar present in the tubers, inulin, contributes no calories as we do not digest it. Yacon is naturally low-calorie — a jar of yacon syrup contains half the calories as a same-sized jar of honey — and its sugar does not raise blood glucose levels.

The root contains 86-90% water and only traces of protein and lipids. It is high in oligofructose (also called fructo-oligosaccharide), a dietary sugar, which the human body does not metabolize, hence its potential use for diabetics and in body weight control. Moreover, increased intake of oligofructose has been associated with improved gut health because of the stimulation of (beneficial) bifidus bacteria in the colon. Carbohydrates (sugars) comprise up to 20 percent of the tubers, but the sugars stored in the tubers include only minimal amounts of glucose, they consist mainly of fructose, sucrose, some oligosaccharides and inulin — sugars that are poorly absorbed in the gastro-intestinal tract of humans.

Yacon stores carbohydrates in the form of inulin, rather than glucose, which means a world of a difference for diabetics and dieters alike. You see, the human body lacks the enzyme necessary to metabolize insulin, so the substance that gives yacon its sweetness passes through the digestive tract unmetabolized. In other words, yacon tuber has a very low glycemic index and very few calories.

As if that's not enough, the tuber can give your body a great balance of 20 amino acids. It is very high in potassium (having one of the highest levels found in any plant) and also high in calcium, magnesium, phosphorus and iron. What else is in this refreshing, low-cal snack? When scientists analyzed fresh yacon tuber, they discovered the tubers consist of 69 to 83 percent moisture, 20 percent sugars (mostly inulin) and 0.4 to 2.2 percent protein. However, when tubers are eaten in their dried form, these figures shift to 65 percent sugars (again, inulin), 6 to 7 percent protein, 4 to 7 percent ash, 4 to 6 percent fiber and 0.4 to 1.3 percent fat. Pay special attention to the figures for the dried form of tuber if you're looking for a healthy, low-cal snack, because dried yacon tuber provides a great alternative to potato, tortilla or even apple chips.

Dried Yacon Slices -- Perfect for that "sweet tooth-attack" snack. Use low-temp driers to ensure organic yacon slices with high nutritional quality. Or infused with Elderberry Juice -- Offer everything that the original yacon slices offer, plus an extra boost of antioxidants and a nice berry flavor. See Curriculum for a food dryer.

Medicinal Uses

Andean lore attributes several medicinal properties to yacon. It controls blood sugar among diabetics. Anti-diabetic medicinal properties were attributed to yacon leaves. Dried yacon leaves were used to prepare a medicinal infusion or mixed with common tea leaves. It is also supposed to cure kidney and digestive problems, and rejuvenates the skin.

Yacon is attributed the following properties: A good treatment for diabetics, Provides high fiber content that helps assist people with digestive problems, low calories but perfect for nutritious diet for obesity, helps prevent kidney problems, good for skin rejuvenation, prevents colon cancer, and fertility enhancer. Yacon tubers is said to aid in diabetes, hypertension, kidney diseases, constipation, insomnia, and even mosquito bites, dog bites, open wound, inflammation, bee sting, etc.

The healthiness of yacon doesn't end there. Unlike olestra -- which many people say upsets your digestive tract and causes stomach cramps, gas and diarrhea -- yacon tuber is actually good for your intestines. Inulin helps keep intestinal flora in balance (the good bacteria that live in your intestines to stop the bad bacteria from spreading). Healthy and strong intestinal flora mean healthier blood, improved skin complexion, enhanced digestion and much more.

The yacon’s oligofructose properties were discovered by ancient peruvians but the modern medicine found out that if the leaves are used in tea, it has the effect of avoiding the peaks that you have when eating sugary or starchy food, when your blood sugar level goes up violently, one of the biggest problems of diabetic people who have high blood sugar levels and whose bodies do not produce or properly use insulin, a hormone that would normally be released to process food.

Research has proven that is beneficial for those with hypertension. By thinning the blood Yacon can lower blood pressure by 5 to 10 percent. It can also lower cholesterol and discourage clot formation. Yacon has a reputation for being a Diabetes but it is also excellent to reduce the hypertension problems.

Dr. H Brams said yacon roots themselves had not been proven to have the same palliative effect as the Yacon leaves. Even so, yacon is now popularly associated in Peru with diabetes, though other benefits such as its laxative quality and ability to help prevent colon cancer and osteoporosis are less well known.

Yacon tubers store carbohydrate in the form of inulin, a type of fructose, which is a suitable food for diabetics. Type II diabetics are not insulin dependant and so can control their blood sugar levels through diet. Plants with the sugar inulin such as Jerusalem artichokes and yacon can be useful additions to their diet. In addition to providing living enzymes often lacking in a constricted diet there is satisfaction in being able to have a sweet juicy treat. Some diabetics have stated that eating even a small piece of yacon has lowered their blood sugar levels. With the ease with which yacon juice can be extracted there is a possible future potential as a commercial crop to make sucrose-free foods for diabetics and dieters. Just like sugar cane, the sugars can be concentrated to obtain a high-fructose sweetener.

Inulin has been the subject of much scientific interest lately. It reportedly stimulates the body’s immune system when injected; but inulin is not absorbed in the gastrointestinal tract and therefore its immuno-stimulant effects have never been observed with oral use. Inulin has likewise been demonstrated to stimulate the growth of friendly bacteria (lactobacilli) in the large intestine. In a study where subjects were given 15 grams of inulin a day for 15 days, the population of Lactobacillus bifidobacteria increased by 10 percent, while at the same time, the population of disease-causing bacteria decreased. Inulin may also prevent precancerous changes in the colon.

Cultivation

The yacon plant can reach six feet in height. Its leaves are dark green and its stems are hairy. South American origin. Small orange daisy flower. The plant takes 6-7 months to reach maturity, although they have been known to crop quite well in a 5 month growing period. Its root system consists of fleshy tubers which look like Dahlia or Kumara (sweet potato), but they are slightly softer and bigger, often reaching 25 cm in length and 10 cm in diameter, and on average weigh about 300g but can weigh up to 2 kg. The skin is brownish, but the meat is white to yellowish. After flowering, top growth withers and dies back and the tubers are harvested. The tubers continue to sweeten as the plant dies back so the main harvest should only take place once all the top growth is dead, (although in warmer areas this dieback is minimal). Don’t leave it too long though, especially in areas that have mild winters, as the plant will start to shoot again as the weather warms up and the days get longer. Harvest tubers mid-late winter. The plant needs to be dug carefully to avoid damage to the crisp tubers. After separation from the central stem undamaged tubers can be stored in a cool, dark and dry place with good air circulation for several months. The average sugar content of the tubers increases during storage because of starch conversion.

Yacon grows successfuly even in poor soils, although it does prefer a warm position in a deep rich soil. It likes sun but has been said to grow well even under trees. Plants are fast-growing and very happy in temperate climates as they are unaffected by day-length. It appears to be drought tolerant although crop will benifit from occasional deep watering in hot dry spells, and is so far pest-free.The top growth is killed back by frost but the tubers can tolerate at least light frosts. The roots are brittle and must be harvested with care to avoid damage. Yields of 38 tonnes per hectare have been recorded in South America. Plants have not been selected for flavour or yield, most roots are exceedingly sweet but some can be fairly bland. Any rizome left in the ground will likely grow a new plant, but Yacon is not superinvasive as it is easy to remove and stays in a localised clump.

Propagation

Division in autumn. Yacon actually produces two types of underground tubers, reddish rhizomes in a tight clump directly at the base of the stem, which can be eaten when young but are mainly used for propagation and large tubers, usually on thin roots 2 - 5cm long, are used as storage organs and do not have the capacity to form new shoots. These are the tubers that are usually eaten. It is relatively easy to separate the rizomes from the tubers when harvesting as they form in a clump that does not break up easily. Just cut the main stems back to about 10cm long and store these stems with their cluster of small tubers in a cool frost-free place. Do not let them dry out. Divide and pot them up in early spring in a greenhouse, under shadecloth or even in a warm spot inside. Plant them out in late spring in deep soft soil after the last expected frosts. Mulch well, yacon will grow up through the mulch, just like potatoes. Little weeding is needed as dense shade is created as the yacon grows. Plants are large and vigorous, so space them at least .5 metres apart. Also propagated by cuttings of basal shoots in early spring in a warm greenhouse. Harvest the shoots with plenty of underground stem when they are about 8 - 10cm above the ground. Pot them up into individual pots and keep them in light shade in a cold frame or greenhouse until they are rooting well. Plant them out in the summer.

Other Uses

Animal Forage
Yacon has potential as a forage crop for animals, the leaves have a protein content of 11-17% and when cut the foliage sprouts again from the underground stems. The tubers may be a good cattle feed, for inulin is rapidly metabolised by ruminants. It is used as a soil protector because of its ability to maintain itself as a perennial species, especially in dry areas. In this case don’t expect a yield of tubers but grow it instead for animal forage.

Bio-Alcohol

The sugars in Yacon have potential in being used to make a bio alcohol for industry.