418 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1941 



there is very little sale for kelp as a food here where the dietary 

 standards differ so radically from those of the Occident. It is valu- 

 able to Japan because of its cheapness and the number of ways in 

 which it can be prepared as food. Most of the kelp is obtained from 

 Hokkaido, the most northern of the main islands of the Japanese 

 Archipelago. The kelps grow on all parts of the coast, but those 

 of highest quality are found on the northeastern coast which is 

 washed by the Arctic current. 



Undoubtedly the most important seaweeds used as food and in 

 industry are those with jelly-making properties that belong to the 

 family Gelidiaceae. Agar is made chiefly from the algae Gracilaria 

 Uclienoides, Gelidium comeum (pi. 2, fig. 2) and other closely re- 

 lated species of Gelidiium. The Chinese introduced it to Japan in 

 A. D. 1662. It was used principally as a substitute for bird's-nest 

 soup stock and as a summer jelly. It is used in Japan, China, and 

 India as an ingredient of soups and sauces, and is also used as a 

 sort of dessert and as a candy. In Japan it is called Kan-Ten 

 which means "cold weather" as the substance made from the algae can 

 only be manufactured during the winter months. The manufactured 

 product is called agar. 



In the early years of its use, or rather before the large agar indus- 

 try was developed, the seaweed was merely boiled to form a mass of 

 jelly, but at the present time the agar of commerce is in the form 

 of sheets, sticks, bars, and flakes. 



Kan-Ten is pearly white, shiny, transparent, tasteless, and odor- 

 less. It swells in cold water but does not dissolve, and is soluble in 

 boiling water and easily forms a jelly. In foreign countries it is 

 Used chiefly where a gelatin is required such as in making jellies, 

 soups, sauces, candies, pasteries, and many desserts, in all of which 

 it is far superior to animal isinglass or gelatin. It is also used for 

 the clarifying of wines, beers, coffee, and other drinks. 



Agar is used to a great extent in the United States. It is very 

 desirable in food manufacture as it jells rapidly and at relatively 

 high temperatures without the assistance of intermediary substances. 

 It has proved very economical because of its high gel strength. Ex- 

 periments have shown tnat agar in bread and pastries, on account 

 of its high moisture-retaining quality, keeps them fresh longer. The 

 confectioner can use it to make a healthful jelly candy with less 

 sugar by using agar in % to 1 percent solutions. For that reason 

 it is very economical. It provides a good body to drinks, and acts 

 as a stabilizer in chocolate drinks and syrups, in which it prevents the 

 forming of sediment. A manufacturer of ginger ale and fruit syrups 

 believes that it sharpens the flavor. Agar has proved to be of great 

 value commercially in the manufacture of sherbets, ice creams, and 



