122 ANNUAL REPORTS OF DEPARTMENT OF AGRICULTURE. 



handling the curd for Camembert which reduces the labor appreci- 

 ably has given a satisfactory product. The brown discoloration of 

 Roquefort, which has given trouble in the past, has been found to be 

 due to delay in wa-apping in tin foil. 



On the basis of the results obtained with Pecorino cheese made 

 at Grove City, another series has been started with the object of 

 reducing the drjpness and hardness. Additional curing-room space- 

 has been provided at Washington, and a considerable quantity of 

 cheese of the Parmesan and Romanello type is being made for long 



storage 



UTILIZATION OF SKIM MILK, BUTTERMILK, AND WHEY. 



Studies have been made on the vapor pressures of skim-milk 

 powder in relation to its aging and solubility. As a powder ages, 

 there is a measurable variation in the amount of water it will absorb. 



It has been found practicable to produce by 14 days' fermentation 

 from 5 pounds of lactose a mixture of 1 pound of acetic and 2.35 

 pounds of propionic acid. This is about 90 per cent of the theoretical 

 yield. Attention is now being given to products obtained by the 

 direct oxidation of lactose. 



Dried whey and dried buttermilk have been furnished to the 

 Animal Husbandry Division for feeding experiments with chickens. 

 In the first half of the 12-month experiment the pen receiving dried 

 whey produced more eggs than any other pen. 



Considerable quantities of dried whey have been made on a small 

 commercial scale at Grove City. About 4 pounds of crude sugar 

 and li pounds of dried w^hey containing about 30 per cent of albumin 

 were obtained from each 100 pounds of whey. The dry whey has 

 been sold at 25 cents a pound to a laboratory making an infant 

 food. This has given a profit over the cost of manufacture. 



DAIRY EXPERIMENT FARM. 



The w^ork at the dairy experiment farm, Beltsville, Md., has 

 steadily increased. An adjoining farm of 129 acres has been leased 

 and is being cleared. This additional land will permit of a more 

 extensive use of pasture and will provide for the natural increase 

 of the dairy herd for several years. Because of the presence of 

 abortion and other genital diseases the health of the herd was not 

 satisfactory. An average of 27 cows and 12 calves have been on 

 experiments of various kinds at all times during the past year, and 

 in addition the cows on official test have provided much valuable 

 data. 



DAIRY CATTLE MANAGEMENT STLTJIES. 



Cows kept under test conditions were found to produce, on the 

 average, about 60 per cent more milk and butterfat than those kept 

 under ordinary herd conditions. Most of the work at present is in 

 determining the effect of each one of the factors responsible for the 

 higher production. So far only 20 per cent of the increase has been 

 satisfactorily accounted for. Five per cent was due to keeping cows 

 in box stalls as compared with stanchions. 



One of the commonly accepted rules of dairying is that cows 

 should be milked at regular intervals. To test this, cows were 



