THE MILK SUPPLY OF CHICAGO 173 



necessary for the condenseries to absorb this surplus, which 

 sometimes works a hardship on that industry. 



PRODUCTION 



At the present time 98 per cent of the milk consumed in 

 Chicago is pasteurized, according to the Chicago Health De- 

 partment. The other 2 per cent is certified milk. A clause 

 in the city ordinance provides for the sale of raw inspected 

 milk, but none is sold, unless certified milk is included under 

 this head. 



All pasteurized milk has been heated in a "holding system" 

 since 1914. A minimum temperature of 140 F. with a min- 

 imum time of 20 minutes is required. Previous to 1914, the 

 4 ' Hash ' ' system was used almost exclusively. 



The largest dealers in the past have advertised the fact 

 that their milk was bottled in the country, and at the present 

 time, this practice is maintained by them, although one of 

 the largest companies has erected and operated a modern plant 

 within the city limits for the past four years. 



The plants located in the country are known as "bottling 

 plants". They are situated as a rule near a railroad track. 

 The milk is delivered at these plants, by the farmers them- 

 selves, between 6 :30 and 11 A. M., depending on the season 

 of the year. In summer deliveries are made early, and 

 in winter late. It is a ruling of the milk distributors that 

 the milk cans be covered with canvas during transit from farm 

 to plant. 



The milk is cooled by the farmer to 60 F. or below, usually 

 by placing the cans in a tank of cold running water. After 

 delivery at the plant, the cans are thoroughly washed and 

 steamed before they are returned to the farmers. Immed- 

 iately after delivery, the milk is pasteurized and cooled to 

 45 F. The milk is then filled into glass bottles; no single 

 service packages are used to any extent. All milk for the 

 retail trade has been bottled since 1891, and that for the 

 wholesale trade is put up in 8 or 10 gallon cans. 



Some of the bottling plants are equipped with separators 

 and separate their own cream for the trade. The skim milk 



