AGAR AND RELATED PHYCOCOLLOIDS 55 



water. Those which chance to lodge in a favorable place grow into plants whicli 

 produce spores in tiny groups of four, known as tetraspores; such plants are 

 termed tetrasporic plants. Mature tetraspores are shed in the water and in turn 

 develop into either male or female plants. It is believed that of each group of 

 four tetraspores, two are capable of developing into male plants and the other 

 two into female plants. In general female plants produce their carpospores in the 

 summer, while tetrasporic plants produce spores in the fall. 



Collection. Irish moss is gathered from May until about the first of September. 

 Old-fashioned methods are still used. The mosser goes out to the beds, usually 

 in a dory, an hour or two before low tide. By means of a specially constructed 

 rake he pulls moss from the rocks until an hour or so after the tide has begun to 

 rise. The rake is composed of tapered steel tines welded to a crossbar so that 

 their bases are very close and the space between the tines wedge-shaped. The 

 angle of the rake and the 12- to 20-foot wooden handle enable the tines to be 

 drawn horizontally across the bottom. Bunches of moss are wedged between 

 the tines and torn loose. An experienced mosser can gather 400 to 500 pounds, 

 fresh weight, of moss during the 3 to 4 hour period of one low tide. 



Drying. Fresh moss is usually washed in large vats of running sea water with 

 motor-driven agitators. Washed moss is then spread on portable racks or the 

 beach to facilitate drying. Since rain would extract much of the gelose, loose moss 

 is quickly raked into piles and covered and the racks are stacked in tiers. If a 

 bleached product is desired, the moss is sprinkled several times with fresh or sea 

 water. Each successive drying results in further bleaching. Factories that extract 

 carrageenin and market it as a dehydrated, purified powder usually use un- 

 bleached moss as pigments are removed in the manufacturing process. If the moss 

 is to be sold in its dry, crude form, or simply pulverized, a clean, bleached product 

 is desired as it brings the highest price. Considerable quantities are marketed 

 in small packages sold at retail. Moss sold for extraction of carrageenin is usually 

 unbleached and is put up in 100- to 200-pound burlap-covered bales. Careful 

 attention must be given to the moisture content of dry Irish moss. If the moisture 

 exceeds about 28 per cent, deterioration by mold growth is very likely to occur; 

 from 15 to 18 per cent is considered ideal. Moss that is too dry is brittle and dif- 

 ficult to handle. Estimate of moisture content is done with good accuracy by those 

 experienced in the drying and packing process. 



Approximately 4 pounds of fresh moss are required to produce 1 pound of 

 dry, unbleached (black) moss of average moisture content; about 5 pounds, fresh 

 weight, are required to produce 1 pound of bleached moss. A large proportion of 

 salt is lost from the bleached moss and sometimes a small portion of the most 

 soluble fractions of its gelose content. Bleached moss also contains a lower average 

 moisture content because more of the sea salts have been removed. 



In 1948 and 1949 fresh moss sold for 2 cents per pound. Moss harvesters prefer 

 to sell it in this condition, but the market is limited because it must be spread and 

 dried promptly or deterioration will take place. Therefore most moss is dried by 

 those who harvest it. Dried moss brought 8 to 12 cents per pound in 1948 and 

 1949. If bleached, the price range was from 12 to 15 cents. Prime quality bleached 

 moss brought from 24 to 39 cents per pound in 1947.* 



** Anon., "Agar- Agar and Irish Moss (Chondrus)," World Trade in Commodities, 5, 

 No. 89, Part 2 (1947). 



