在沸水中极易分散成溶胶，在冷水中不溶，但能吸不膨胀成胶块状，溶胶液呈中性反应。食用时不被酶分解，所以几乎没有营养价值。琼脂易分散于热水，即使0.5%的低浓度也能形成坚实的凝胶。1%的琼脂溶胶在42℃固化，其凝胶即使在94℃也不融化，有很强的弹性。琼脂溶胶的凝固温度较高，一般在35℃即可变成凝胶。琼脂的吸水性和持水性高，干燥琼脂在冷水中浸泡时，徐徐吸水膨润软化，可以吸收20多倍的水。琼脂凝胶的耐热性较强。琼脂的耐酸性比明胶与淀粉强，但不如果胶琼指可用作食品增稠剂、蚕丝上浆剂、缓泻剂，以及药品的胶粘剂、增稠剂和胶囊，还可作为细菌培养基、固定化酶载体、细菌的包理材料和电泳的介质。还可用于病毒，亚细胞粒子和大分子的过滤分离，以及血清抗原或抗体的观察。ADI（每日允许摄入量）不需要特殊规定。
Agar disperses very easily in boiling water to form a sol, is insoluble in cold water but can absorb water and swell into gel-like lumps; the sol solution exhibits a neutral reaction. It is not broken down by enzymes during digestion and therefore has almost no nutritional value. Agar disperses readily in hot water, and even at a low concentration of 0.5%, it can form a firm gel. A 1% agar sol solidifies at 42°C, and the resulting gel does not melt even at 94°C, exhibiting strong elasticity. The gelation temperature of agar sol is relatively high, typically forming a gel at around 35°C. Agar has high water absorption and water retention capacity; when dry agar is soaked in cold water, it gradually absorbs water, swells, softens, and can absorb more than 20 times its weight in water. Agar gels have strong heat resistance. Agar is more acid-resistant than gelatin and starch, though less so than pectin. Agar can be used as a food thickener, a sizing agent for silk, a laxative, and as an adhesive, thickener, and capsule material in pharmaceuticals. It can also serve as a bacterial culture medium, a carrier for immobilized enzymes, a material for bacterial encapsulation, and a medium for electrophoresis. Additionally, it can be used for the filtration and separation of viruses, subcellular particles, and macromolecules, as well as for the observation of serum antigens or antibodies. The ADI (Acceptable Daily Intake) requires no special specification.
K2211080
危险品化学品经营许可证（带存储）