What is Agar?

Agar is a substance with gelatin-like consistency and is derived from red algae. It is commonly used in various parts of Asia in preparing sweets and desserts.  Sometimes called “agar-agar”, this substance is specifically sourced from the cell walls of a particular algae called “agarophytes”.  In other countries, a similar substance is called by a different name.  In China, agars are referred to as China grass and in Japan it is called Japanese isinglass.  But the most common reference to this gelatinous substance is “agar” or “agar-agar”.

The substance agar is widely used in the food industry.  Agars can be used to thicken soups and broths and may serve as vegetarian alternatives to standard jelly.  Since agars are plant-based gelatins, vegetarians around the world can have this option in terms of marshmallows and jelly beans.  For those watching their weight, agar food preparations are also said to act as laxatives aiding in the food digestion process in the intestines.  Breweries also use agars as a clarifying agent resulting to increased quality of brewing products.  Other desserts like ice creams may also have agar as one of the ingredients to add volume and thickness to the cream.  Although agars are a bit slimier than protein-based gelatins, they still are widely used for their thickening properties.  Just like protein-based gelatins, most agars are sold in powder form.  Water is also the only other basic ingredient that should be mixed with agar to make a gelatinous substance or food item.

Aside from its use as food additive, agars are also utilized by microbiologists as growth medium.  When scientists try to grow a culture of certain substances and/or organisms, agars provide a stable base for growth.  And since it is not based on protein, agars cannot easily be digested by bacteria, making it a good choice for experimentations.  And similar to food preparations, other ingredients may also be added to the agar base to serve as food for microbes that are being studied.