2 BinCLETIl^ 1096, U. S. DEPAETIMEXT OF AGRICULTUEE. 



CRUSHING PEANUTS, 



VARIETIES USED.2 



The Spanish variety is the one grown principally for the production 

 of oil. The meats of this variety have a higher oil content than those 

 of any other, \Yith the possible exception of the Valencia, or Tennessee 

 red. It has a higher proportion of meats to hulls than any other 

 variety and is adapted to a %vider range of soil and climatic conditions. 



PROCESSES. 



Most of the crushing of peanuts is done in cottonseed-oil mills, 

 which are well adapted to this work. These mills run for part of 

 the season on cotton seed, when it is available, and for another part 

 of the season on peanuts. Thus a close relationship exists between 

 the cottonseed-oil industry and . the peanut-oil industry, although 

 many mills crush peanuts exclusively. 



The processes for crushing peanuts in this country are of two dis- 

 tinct types — the hydraulic, which is intermittent, and the expeller, 

 which is continuous. 



HTDEACLIC PROCESS. 



From the storehouses to which they are brought by the farmers the 

 peanuts are run through shakers or conveyors having fine sieves, to 

 remove the sand and fine dirt, and then through larger sieves, con- 

 sisting of perforated plates having holes large enough to permit the 

 peanuts to drop through, thus separating them from the sticks, 

 vines, stones, and larger pieces of trash, which pass out from the tail 

 of the machine. 



The peanuts are next taken in screw conveyors to the huller. 

 Sometimes this is an ordinary cottonseed bar huller, or a slight 

 modification of it, consisting of a cylinder the lower part of which 

 is made of sharp-edged steel bars, with revolving sharp-edged bars 

 attached to a frame within. The peanuts are chopped as they pass 

 between the sharp edges, and the meats and hulls pass out through 

 slits between the bars. Most mills, however, use the so-called disk 

 huller. This consists of a cylinder the lower half of which is made of 

 steel bars properly spaced, having inside rough-faced disks, some re- 

 volving and others stationary, placed side by side, so that the revolv- 

 ing disks alternate with the stationary disks. Peanuts are fed in at the 

 top, the hulls are rubbed off as they pass between the disks, and the 

 hulls and meats pass out tlirough the slits between the bars below. 



The stock is next conveyed to a shaker machine, where the meats 

 are separated from the hulls by means of sieves and an adapter 



2 A complete description of the varieties of peanuts grown in the United States is given in Farmers' 

 Bulletin 751, copies of which may be had on appUcation to the Division of Publications, U. S. Department 

 of Agriculture, Washington, D. C. 



