What is Agar?
Agar-agar, usually seen abbreviated as agar, is a gelatinous substance derived from red algae. There are a number of uses for agar, although most people are familiar with it as the culture medium in petri dishes. Agar is also perfectly edible, and in addition to appearing in regional cuisine, it is also used as a thickening agent in candies and other foods. Since agar is derived from plant material, it has the advantage of being vegetarian, unlike gelatin derived from animal sources. In microbiology, agar is an important part of the equipment in a laboratory. Because agar is not protein-based, it is not as readily digested by bacteria. When scientists are trying to grow a culture, agar is the growth medium of choice, since it will not turn into a cloudy bacterial soup like animal derived gelatins can. The agar can be enriched with nutrients for the bacteria to feed on, but the agar itself will remain stable. In cooking, agar is extremely useful. In parts of Asia, agar is used as an ing
Agar is the standard material used in microbiological and mycological culture work for gelatinizing nutrient broths. It is derived from certain seaweeds and cannot be directly digested by most organisms. It is material, with the addition of various nutrients, that is poured into petri dishes. It is used to germinate spores and isolate mycelium away from contaminates.
Agar is a polysaccharide found in the cell walls of some red algae from which it’s extracted by boiling. This raw agar is then purified. When agar is dissolved in boiling water and left to cool it will form a gel (very much like gelatin). It can be bought in many different grades from food-grade to purified tissue culture grade. It’s main uses are in the field of microbiology, tissue culture and food preparation (as a vegetarian substitute for gelatin). Why is agar important? We use agar as a gelling agent for nutrient media. By adding nutrients (agar itself does not contain digestible compounds) a nutrient base can be made on which mushroom mycelia can be cultivated in a flat two-dimensional way. It can not be substituted by gelatin since gelatin is digestible and does not gel after autoclaving.
