P.\S'l'iaiKI/.A'|-|()X TF.ArPERATUkl'-.S 



203 



nu'thod of hcatin,L!; has ]>vL-n rrt'nnniicnded 1)\' liini Icir the [ii-ir- 

 posc of (lcstro\in,t!; the cii/yi^os in the cream. lUittiT nuule trom 

 cream thus treated lias shown unusually i^'ood kee])in,!j; qualities, 

 and he reports that it does not ,<(o iish}- when placed in storage. 

 One of the adA'antages of jiasteurization is that it destroys all the 

 pathogenic micro-organisms in the cream if an}- l)e present. 

 Efficient pasteurization destroys from 99.5 to 90.9 ]>vr cent of 

 the organisms present in cream. Pasteurization, ho\ve\'er, does 



Fig, (if).— Tin- Simplex regenerative pasteurizer (a[)art). 



not put poor cream in a condition where good Initter can be 



made from it. 



Pasteurization and sterilization are not the same. The 

 latter means that ntilk or cream, or any other licjuid substance, 

 has been heated so often or to a high enough tem.perature to 

 entirely destro}- ever\- li\'ing micro-organism present. In order 

 to get a substance tlioroughly sterilized without heating under 

 pressure, it is essential that it be heated about thirty minutes 

 on each of three or more consecutiA'e days. 



