540 Journal of Agricultural Research vol. xx,No. 7 



methods that a farmer should use are given. From the study of Tables 

 I and II of this paper it is plain that more care is needed on the part of the 

 average farmer before he can expect to secure a silage of good quality. 

 If the suggestions embodied in farmer's bulletins of the United States 

 Department of Agriculture are followed, the farmer will not only be 

 rewarded with a silage of good quality and high feeding value but he 

 will also avoid the loss of stock. 



ACIDITY OF SUGAR BEET TOP SILAGE 



Investigations of many types of silage by the writer x and others have 

 indicated that in practically all silages that have undergone a normal 

 fermentation there results an acidity in which the chief acids are lactic, 

 acetic, and propionic, their relative importance decreasing in the order 

 named. In the sugar beet top silage it was desired to study the acidity 

 of several samples to learn what types of acids were formed in the silage 

 found on the average farm. With this idea in mind, several of the 

 samples sent in to the experiment station were examined. The Duclaux 

 method 2 was used for estimating the volatile acids, and the zinc lactate 

 method was used for the nonvolatile or lactic acid. The algebraic and 

 graphic methods described by Gillespie and Walters 3 were used in 

 calculating the individual volatile acid after they were identified by the 

 qualitative tests suggested by Dyer. 4 The results on the volatile and 

 nonvolatile acids are given in Tables III and IV. Table III gives the 

 results on the wet basis and Table IV gives the results on the moisture- 

 free basis. 



An inspection of Tables III and IV shows that the acids developed in 

 the sample of sugar beet top silage are not similar to those usually found 

 in the corn silage. Corn silage contains lactic, acetic, and propionic 

 acids. The proportion of lactic to the two volatile acids is usually about 

 1 part to 75 hundredths, while the proportion of acetic to propionic is 

 usually 1 part to one-tenth. Butyric acid was never found in silage that 

 was classed as good corn silage. It was found, however, in partially spoiled 

 samples. Hence the conclusion was reached that silage containing buty- 

 ric acid has undergone an abnormal fermentation. 



'Neidig, Ray E. acidity of silage made from various crops. In Jour. Agr. Research, v. 14, no. 

 10. P- 395 - 409- 1918. Literature cited, p. 408-409. 



2 Duclaux, E. recherches sur les vtns. deuxif.me mf.moire: sur les acides volatils du vin. 

 In Ann. Chirn. et Phys., s. 5, t. 2, p. 289-324. 1874. 



— traite de microbiologie. t. 3, p. 388. Paris, 1900. 



'Gillespie, L. J., and Walters, E. H. the possibilities and limitations op the duclaux method, 

 for the estimation of volatile acids. In Jour. Amer. Chem. Soc, v. 39, no. 9, p. 2027-2055, 3 fig. 1917. 

 Literature cited, p. 2055. 



<Dyer, D. C a new method of steam distillation for the determination of the volatile 



FATTY ACIDS, INCLUDING A SERIES OF COLORIMETRIC QUALITATIVE REACTIONS FOR THEIR IDENTIFICATION. 



In Jour. Biol. Chem., v. 28, no. 2, p. 445-473, 2 fig. 1917. 



