Both Agar and Gelatin are essential ingredients in the preparation of desserts worldwide. The main difference between agar and gelatin is the source from which they are derived. Agar is a vegetarian substitute for Gelatin since it is derived from a plant and has higher gelling properties.
edit Differences in source
While agar is derived from red algae, gelatin is made mainly from the collagen present in pork skins, pork and cattle bones, or split cattle hides. Contrary to popular belief, horns and hooves are not used.
edit Properties of Agar vs Gelatin
Agar melts at 85 degrees Celsius and solidifies between 32 and 40 degrees Celsius. Gelatin melts at 35 degrees Celsius and solidifies at low temperatures but the exact gelling would depend upon the concentration and time of standing.
edit Differences in Form & Shape
Agar is white and translucent and sold as either strips or as a powder, originally eaten in Japan. Gelatin is colorless, translucent and odorless solid substance and comes in the form of granules, powder or sheets.
edit Nutritional Properties
Agar is low in saturated fat and cholesterol and high is calcium, folate, iron and vitamins amongst others. It is ideal for people interested in weight loss and maintaining good health. Gelatin, although comprises 98 to 99% protein, if eaten exclusively results in net loss of protein and malnutrition.