Agar, also known as agar-agar, is a jelly-like substance consisting of polysaccharides obtained from the cell walls of some species of red algae, primarily from "ogonori" (Gracilaria) . It is a translucent, plant-based, gelatin-like substance extracted from algae with many uses in the culinary arts and beyond. Here are some key facts about agar:

• Composition: As found in nature, agar is a mixture of two components, the linear polysaccharide agarose and a heterogeneous mixture of smaller molecules called agaropectin.

• Uses: Agar has been used as an ingredient in desserts throughout Asia and also as a solid substrate to contain culture media for microbiological work. It can be used as a laxative, an appetite suppressant, a vegan substitute for gelatin, a thickener for soups, in fruit preserves, ice cream, and other desserts, as a clarifying agent in brewing, and for sizing paper and fabrics.

• Preparation: Agar can be boiled in water until the solids dissolve to make jellies, puddings, and custards. It can be used as an addition to or as a replacement for pectin in jams and marmalades, as a substitute for gelatin for its thickening properties, and to make dental impressions.

• Benefits: Agar gives a sensation of fullness, leading it to be used in some diet products. In Asia, it is also sometimes used as a digestive remedy for upset stomachs. It can also be used as a laxative or to thicken soups, sauces, or preserves.

Agar can be found in Asian supermarkets, health food stores, or online, as flakes or powder. It is suitable for use by vegans as a substitute for gelatin, as it is derived from plants, not animals.