10 PEANUT BUTTER. 



The manufacturers who are producing the finest grades of peanut 

 butter are employing more than one variety in its composition. 

 When made entirely of Virginia peanuts, the product is lacking 

 in smoothness, and the addition of some Spanish stock greatly 

 improves its consistency. Peanut butter composed entirely of Span- 

 ish peanuts is very smooth, but does not possess as fine a flavor as 

 that made from a blend of equal parts of the Virginia and Spanish 

 varieties. 



A variety of peanut known as " Java " is frequently imported and 

 is used to a limited extent for the manufacture of peanut butter. 

 This variety makes a very smooth product, but as the nuts have 

 a tendency to become strong and rancid they can be used only 

 when strictly fresh. 



GRINDING. 



The manufacture of peanut butter in quantities requires the use of 

 special grinding machinery. "V\niile peanut butter can be made for 

 home use with the aid of an ordinary meat grinder, machines of this 

 class do not grind finely enough for commercial work. Peanut but- 

 ter requires to be ground to a fine granular form rather than to 

 a pasty consistency. The oil in the meats is contained in minute 

 capsules or cells, and it is desirable to have these cells broken apart 

 rather than crushed and the oil liberated. For this reason worn 

 or smooth grinding plates do not give good results when run closely 

 together, owing to the rubbing or smoothing of the pulp between 

 them. When ground to a paste it lacks proper consistency and does 

 not hold up well. 



The grinding produces considerable heat, and care is necessary to 

 prevent scorching. One or two factories are equipped with grinders 

 in which the working parts are surrounded by a water jacket similar 

 to that around the cylinder of a gasoline engine. By this means a 

 circulation of water through the jacket controls the temperature of 

 the burrs. By connecting the jacket to both hot and cold water pipes 

 and with the use of a thermometer similar to those emplo3^ed in 

 heating systems, the operator, by means of conveniently arranged 

 valves, can absolutely control the temperature of the grinder. 



Figure 5 shows a large motor-driven grinder Avhich is equipped 

 witn a cooling device. This gi-inder requires a 30-liorsepower motoi- 

 to operate it and will grind 21 pounds of meats a minute. Most fac- 

 tories are, however, equij^ped with smaller grinders of the type shown 

 in figure 6. The smaller machines do not have so great a tendency 

 to become overheated as do the larger ones, but in all cases where 

 some method of cooling is not provided it will be necessary to run 

 the machines at a moderate speed or allow them to cool occasionally. 



[Cir. 98] 



