134 THE STERILISATION OF COPE A 



so that nothing remains which will, of itself, conduce 

 towards, or expose the product to, the ravages of 

 vermin, or injury from excessive heat. This is 

 now affirmed by science, which asserts that steri- 

 lisation alone can ensure these results. 



The first step in the process is to see that the 

 natural fat in the nut is so preserved that there is 

 no tendency towards oxidisation ; or, in other 

 words, rancidification. 



There are in use several processes in. which 

 oxygen, one of the finest disinfectants, bleachers 

 and preservatives known to science, is employed ; 

 the copra, or to be more exact, the oil contained in 

 the copra, is brought into contact with just the 

 necessary proportion of the gas to secure the 

 desired result. Most of these processes have been, 

 more or less, adaptations of the Mercer process, 

 which was originally designed for the bleaching 

 and sterilisation of cereals, particularly flour. It 

 is so well known that no extended reference to the 

 process is necessary at this point. Its principal 

 feature is the injection of a charge of oxygen, 

 accompanied by electrical treatment. Flour or 

 other cereal products so treated are chemically 

 bleached, sterilised and preserved, while the process 

 itself results in the maturing of the product in less 

 time than would be necessary under normal con- 

 ditions. 



The Hoffmann process for the sterilisation of 



