Konnyaku / Yam Cake

Konnyaku (こんにゃく in Japanese) is a traditional Japanese processed food made from yam. It is often used in stews, stir-fries, etc. As konnyaku has a particular smell, it should be parboiled or stir-fried without any oil or water before use. If you tear it by hand or make incisions with a knife, the flavors of the dish you include it in will penetrate better. There are many varieties, such as konnyaku sheets, balls, threads, and sashimi konnyaku, which can be eaten raw. There is also black konnyaku mixed with seaweed, and white konnyaku without any seaweed.

Konnyaku is a highly alkaline food with a pH value of 11, which is very rare amongst foods. This is because calcium hydroxide is used in its manufacturing process. This also means that konnyaku contains calcium. Konnyaku is rich in dietary fiber, which helps to eliminate waste products from the body. The dietary fiber contained in konnyaku yams is rich in soluble dietary fiber called glucomannan; however, it becomes insoluble dietary fiber during the gelatinization process.
One example of a kyonnyaku product is called shirataki noodle. It is said that shirataki, which is formed as thin noodles, helps calcium absorption because its wide surface area makes it easier for calcium to be dissolved. Konnyaku is both very low in calories and filling, so it is good to use to bulk up dishes when limiting caloric content. 

Wash konnyaku before storing and wipe off the water thoroughly. If you soak it in an airtight container filled with water and refrigerate it, it can be stored for about a week. Or, if you wipe off the water and put it in an airtight container with the air removed, it can be stored for about a month in the freezer. The texture will change slightly, but this will have little effect if you use it in dishes like stews.

Konnyaku has become increasingly popular as a health food in Europe and North America over the past decade, due to its low calories and plant-based properties. Since thread konnyaku can also be used as a substitute for pasta, it is sometimes sold in supermarkets in North America under names such as "Miracle Noodles" and "Skinny Noodles."