Konjac, also known as elephant yam, is a corm—like a bulb or tuber but actually just an underground swelling of the stem—used in cooking in East and Southeast Asia. One of its most salient properties is that it is low-carb, making it very popular with the Keto crowd. But those looking to slash their starches are not the only ones who can reap its benefits. This corm can also help lower cholesterol because it is high in fibre, a trait that also makes it a panacea for gut difficulties. Its special fibre, called glucomannan, gives you the feeling of being full while being low-calorie, making konjac the darling of dieters.
Konjac is used as a thickener (in soups or as a gelatin substitute). But its most well-known use is in making shirataki noodles or shirataki rice, which are low-calorie alternatives for these normally carb-heavy staples. Douse shirataki noodles in garlic sauce and add spinach, or use them as the baseline to set the smooth vamping of peanut sauce against the brazen riffs of snap peas and cherry tomatoes.
Read on for a small encyclopaedia of facts about this curious corm.
This is the 'academic' name for konjac, a plant belonging to the Araceae family that is farmed in China, Korea, Japan, Taiwan and South East Asia.
Konjac noodles are perfect for 'absent-minded' cooks because even after one hour’s boiling it is impossible to overcook them.
This term used for the bulb of this plant, which looks like a large beetroot and can even weigh up to 4 kg with a diameter of 25 cm. It is used to make flour for traditional Japanese noodles, among other things.
Konjac (pronounced "kohn-yak") is also known as konnyaku, gonyak, jǔruò, konjac potato, voodoo lily, devil’s tongue or elephant yam.
This is the abbreviation used to identify konjac gum. If you believe you have never eaten it, think again: it is used in chewing gum, jelly and jelly sweets.
Glucomannan flour is made from konjac. In Japan, where it is known as 'konnyaku', it is the number one ingredient (and the only one if we exclude water) for making shirataki. It is also used for making biscuits and for thickening and emulsifying soups and sauces.
More specifically, it is a glucose and mannose based polysaccharide extracted from the konjac corm. When coming into contact with water, it forms a gel that can increase to 60 times its original volume.
This is the name attributed to brown alga characterised by its pronounced flavour and valuable nutritional properties. It is used to add flavour and colour to konjac noodles, which would otherwise be white and rather bland.
Close relatives of shirataki, but slightly darker in colour owing to the addition of algae to the dough: they are mainly to be found in the Kansai region and appear in the famous 'sukiyaki' recipe, a Japanese dish that is a meal on its own and is typically consumed during the New Year celebrations. As well as konjac filaments, the dish also contains strips of beef and vegetables cooked in a stock with soy sauce, sugar and mirin (rice wine), further enriched by tofu, spring onions, shitake or enokitake mushrooms.
The preparation of 'Thai drunken (konjac) noodles' calls for a generous amount of this well-known green chilli pepper. Plus tamari sauce (soy), a spicy hot sriracha sauce and, finally, lime, onion, garlic, unrefined cane sugar, red and yellow sweet peppers.
Konnyaku Hyakusen (100 recipes for Konnyaku)
This is the title of a popular recipe book published in Japan in 1846, with one hundred recipes for using konjac in various ways, many of which are still in vogue today and represent a cornerstone of the Japanese culinary tradition
These are jellies packed and sold in plastic tubs. Also known as 'konjac jellies', they have a fruit centre. Unlike other jellies, however, they do not immediately melt in the mouth and in fact need to be chewed at length to avoid the risk of suffocation. For this reason, their sale has been banned in the United States, Canada and the European Union. Nevertheless, in Japan they are still widely marketed but the foremost producer of snacks and sweets made from konnyaku gelatine, the Mannon Life company, invites consumers to break the product up into small pieces before giving it to children.
Miraculous? They certainly are for compulsive dieters and all those who, for health reasons, need to keep an eye on their weight because konjac noodles are composed of 97% water and 3% fibre. In other words, this means that they make you feel full with a calorie intake that is close to zero.
Nutritional? Not at all!
While ensuring an intake of 16 different types of amino acids and despite being rich in minerals such as calcium, phosphorus, iron, zinc, manganese, chrome and copper, konjac is not a nutritious food. There is a story to prove it: in the sixties, the Japanese writer Soichi Ohyakeb decided to follow a diet consisting of nothing but konjac. He died of malnutrition.
A typical Japanese dish for the winter months featuring konjac noodles, better known as 'shirataki'. In actual fact, it is a dashi broth flavoured to various extents with soy sauce, to which hard boiled eggs, daikon radish and little dried fishcakes are added, along with vermicelli-type noodles.
In South Korea, the konjac bulb is used instead of potatoes.
Since their weight increases considerably when in contact with water (up to 2.5 times the original weight), remember that 50 g of noodles make a particularly large portion.
Dried konjac noodles require 5-7 minutes’ cooking in salted boiling water, after which they should be strained and rinsed in cold water to eliminate the sugar used in the drying process. However, those sold in preserving liquid need a bit more attention, also to eliminate the strong aroma they give off when removed from their liquid. So, rinse them several times under running cold water and then cook them in salted boiling water for a couple of minutes. Alternatively, once strained they can be tossed straight into a frying pan without fat for 3-5 minutes but, if you opt for this method, they will retain their strong (almost fishy) flavour. Once cooked, you just need to stir fry them (in a pan or wok) with seasonings or add boiling broth (if you are making soup) before serving.
In Japan, these popular noodles made from glucomannan flour are sold either dried or soaked. To make them, the glucomannan gelatine mass is extruded in exactly the same way as ito-konnyaku noodles which, on the contrary, once used to be hand cut into fine strips.
Konjac tends to be chewy, a characteristic that is only slightly less evident when it is cooked. However, some producers have discovered that by adding tofu to the basic mixture, they obtain a less “elastic” consistency.
One of the many condiments that can be used to heighten the enjoyment of shiataki is Japanese umeboshi made from plums (ume), also in its red fermented version with shiso: the acidic saltiness resulting from the maceration of fruit in salt enhances and confers character to the blandness of the noodles.
Konjac is widely used in vegan cooking as a substitute for animal gelatines. In Chinese cuisine, for instance, after being jellified and cut into very fine strips, it replaces shark’s fin in the eponymous soup dating back to the Ming dynasty. It is also a popular substitute for meat in the vegetarian diet of Shojin monks.
The literal meaning of the word 'shirataki' is white cascade, a term that well describes the pale appearance of these noodles made from konjac flour.
XII to XVIII century
It would seem (here the conditional tense is mandatory) that konjac was brought to Japan from China and Korea in or around the VI century, and was first used as a medicinal product rather than an actual foodstuff. It slowly earned a place for itself in cooking during the Kamakura period (1185-1333), before becoming widespread from the XVII century onwards. Since 1776, when the Japanese perfected the technique of making flour from konjac, it caught on to such an extent that it almost became more popular than rice.
One of the many terms used to indicate konjac-based products: a prime example being 'yam noodles' (and 'white yam' is often the term used to identify konjac root). To be precise, however, it must be said that yam is actually a tropical tuber rich in starch belonging to the dioscoreaceae family.
Zero and zero point
Konjac is totally gluten-free and has a negligible amount of calories: 100 g amount to no more than 10 kcal. Furthermore, they only contain 0.5 g of carbohydrates and a scarce 0.3 g of proteins and fats.