4S0 KXPKHIMKNT STATION HKCOHD. 



Addilioiial rosulls ohtaiiied aiv as follows: " Tliero was no variation in 

 v.alcr content iM-twecii half woikod and workt'd l)utlcr or aftt'r llic tliird 

 revolution of tlie cliiirn until workinj; was coinplctod. There was no differ- 

 ence ill et)niiiosition of l)utter made from cream lield 1 to li liours and that 

 held 12 to ir> hours at churning temperature, liutter of the same composition 

 can l)e m.ide from either i)astenrized or uni)asteurized cream. Dry and wet 

 saltiuK methods are identical as far as composition is concerned." "The 

 jtercentage of water in butter is affe<-ted by the make of churn. ChnrniuK 

 of butter washed with water differinj; 10° in tempei'atnre, produced butter 

 with an averafie difference in water content in 40 comiiariscms of 1.!>'.I iter 

 cent." 



In comparing the water content of butter in the churn with that from tubs 

 24 hours later and from one of these tubs melted, the average water content 

 in 12 samples was found to be from the chum 14.56 per cent, from the unmelted 

 tubs 13.84 per cent, and from the melted tubs 14.20 per cent. In another lot 

 of 12 samples the average water content in tubs 24 liours after packing w-as 

 13.93 per cent, from the same tub, frozen, after 6 or 7 months in storage 12.94 

 per cent, and from the same tub melted 13.07 per cent. 



In 1907 the average butter fat content of the cream each day for 56 churn- 

 ings was 452.57 lbs. and of this amount 447.15 lbs. was recovered in the 

 butter. The only loss being in the buttermilk. From this, " it is reasonable 

 to conclude that the tub sample quite accurately represents the average com- 

 position of the butter." In 1908 from 80 churnings the average amount of 

 butter fat received each day was. according to the ])atron's test, 890.79 lbs. ; 

 by the test before the starter was added 803.2 lbs.; and by the test after the 

 starter was added 89.2.71 lbs. The average butter fat recovered was accord- 

 ing to the churn samples 883.43 lbs. and from the tub samples 892.57 lbs. 



The average overrun when based upon butter fat churned was 20.5 per cent, 

 the highest overrun being 26.7 per cent and the lowest 15.3 per cent. " The 

 greatest factor influencing overrun obtained in creamery operation, is the 

 sampling and testing of the milk and cream received. An error of 0.1 per 

 cent in testing 4 per cent milk and 1 per cent in 40 per cent cream will alter 

 the overrim 3 per cent." 



As to the effect of the composition of butter upon quality, scores by 5 differ- 

 ent judges indicate that a reasonable variation in comjtosition does not affect 

 quality. 



Keeping qualities of butter, I, General studies, W. S. Saykr, O. Rahn, 

 and Bell Farrand (Michigan 8ta. Tech. Bill. 1, pi>. 5-61, fig. 1). — The investi- 

 gations reported in this bulletin were undertaken to obtain basic data for 

 further work on special problems connected with the keeping quality of butter. 

 Twelve lots of butter w^ere obtained in May and June from different creameries 

 and put in storage at temperatures from +20 to ■ — 10° C The butter was 

 scored by experts when fresh and from time to time during storage. The 

 liistory and scoring of each sample is given in detail. 



With few exceptions all samples kept in storage above the freezing point had 

 become unfit for use before November. In most cases they were very rancid, 

 but no other flavors were noted except moldiness. 



The water content of all the samples was very uniform, ranging from 12.07 

 to 14.67 per cent. The salt content had a greater range, from 1.06 to 3.78 per 

 cent. These factors were thought to show no diffei'ence in the keeping quality. 



The use of a starter in preparing the cream for churning appeared to have a 

 decided influence upon the scores, for without a single exceiition the average 

 scores of 8 lots where a pure culture starter was not used were lower than the 



