Agar, Bacteriological is a gelifying agent used for the cultivation of microorganisms in a laboratory setting. Agar is a phycocolloid composed of 70% agarose and 30% agaropectin, and extracted from red-purple algae, mostly Gelidium spp. In this product, the naturally occurring pigments, salts, and miscellaneous matter have been reduced to a minimum. Agar is a gel at room temperature and remains firm at temperatures up to 65 ºC. In order to gelify, agar must be dissolved, heated to its melting temperature (85-91ºC) and cooled down to 34-37ºC.