416 EXPERIMENT STATION RECORD. 



bacteria and the cylinder with its contents is kept in a warm place until the 

 flax residue sinks to the bottom. This indicates that the fermentation is over. 



Standard specifications for the purity of raw linseed oil from North 

 American seed {Jour. Indus, and Enyln. Chcm., 6 (11)14), No. 2, p. IG.'t). — The 

 American Society for Testing Materials has issued a compilation of the reports 

 of the commiUec on preservative coatings for structural materials, from 1903 to 

 19i;>. Specifications for the purity of raw linseed oil from North American 

 seed have been adopted, and raw linseed oil from North American seed must 

 conform to the following requirements: Specific gravity at 15.5° C, 0.936 to 

 0.932, or at 25° 0.931 to 0.927; acid number 6; saponification number 195 to 189; 

 unsaponifiable matter 1.5 per cent; refractive index at 25° 1.4805 to 1.479; 

 and iodin number (Ilanus) 178. 



Methods of lesting are <lescribed. 



The analytical constants of hydrogenated oils, C. Ellis (Jour. Indus, and 

 Engin. Chcm., 6 (VJUf), No. 2. pp 117-122}.— The hydrogenation of oil changes 

 the constants wherewith the fats and oils are usually partially identified to such 

 an extent that identification is made much more difficult than heretofore. This 

 article gives most of the available literature on the topic. 



Hydrogenation of oils, C. Ellis (New York, 1914, PP- X+3//0, fiffs. 145). — 

 In addition to the hydrogenation of oils, the work deals with catalyzers and 

 catalysis and the generation of hydrogen. Some of its contents are the analyt- 

 ical constants of hydrogenated oils, edible hydrogeuated oils, uses of hydroge- 

 nated oils and their utilization in soap making, hydrogenation practice, the 

 hydrogen problem in oil hardening, water gas as a .source of hydrogen and the 

 replacement of carbon mouoxid by hydrogen, liquefaction and other methods for 

 the removal of carbon dloxid, action of acids on metals, and miscellaneous 

 methods of hydrogen generation. 



The effect of pressure on certain micro-organisms encountered in preserv- 

 ing fruits and vegetables, B. H. Hite, N. J. Giddings, and C. E. WkiVKley. jb. 

 (West Virginia 8ta. Bui. 146 (1914), PP- 67, figs. 29).— The work previously 

 noted (E. S. R., 11, p. 583), which was done with milk, has now been extended 

 to fruits (peaches, pears, blackberries, raspberries, plums, and tomatoes), A-eg- 

 etables (corn, peas, beans, beets, radishes, and potatoes), and grai>e and apple 

 juice. 



From the investigations it appears that pressure destroys the organisms 

 largely responsible for the spoilage of sweet rii>e fruits. In the case of grape 

 juice a pressure of 100.000 lbs. for 10 minutes stopped fermentation. " Two 

 samples inoculated with yeast were examinetl at the Boston Biochemical Lab- 

 oratory as follows: An old sample fermenting rapidly when subjected to 75,000 

 lbs. for 30 minutes; a fresh sample receiving 25.000 lbs. for 16 hours. In each 

 case an extended series of inoculation tests gave negative results. Inoculated 

 with yeast after standing several years, the compressed samples fermented 

 rapidly." 



A pressure of 30,000 lbs. came to be regarded as the lowest that would prob- 

 ably be worth applying in practice. 



Apple juice subjected to 60,000 to 80.000 lbs. for 30 minutes did not later 

 develop gas and remained sweet. Two one-month-old samples were examined 

 and found sterile. Apple juice kept for five years, after being subjected to a 

 pressure of from 90.000 to 120.0(X) lbs., remained good and had an excellent odor 

 and taste. Peaches and pears exposed to pressures of 60.000 lbs. for 30 minutes 

 never spoiled, and samples kept for five years were in good condition. Plums 

 also kept very well. Raspberries and blackberries usually underwent fermenta- 

 tion, and the samples which remained good were not always those subjected to 

 a high pressure. 



