1921.] Wright.—Chemical Technology of Meat Industry. 
155 
\ 
CHEMICAL TECHNOLOGY OF THE FROZEN - MEAT 
INDUSTRY.* 
By A. M. Wright, A.I.C., F.C.S., Chief Chemist, New Zealand Refrigerating 
Company (Limited). 
PART III. 
Wool. (28, 30, 31, 34, 36, 37, 39, 40, 42.)t 
The sheep and lamb skins after their removal from the carcase are con¬ 
veyed to the fellmongery, and are at once placed in washing-machines, 
which usually are merely vats fitted with a revolving paddling arrange¬ 
ment to ensure that a more or less thorough washing of the skins is 
effected. 
The blood adhering to the skin and wool, as well as the dirt and sand 
which are inevitably present upon all skins, are removed in part from the 
wool and skin by this initial washing, the importance of which can hardly 
be stressed too much. If the wool is thoroughly cleansed the market value 
is enhanced; for, after all, the buyer, who has in view the ultimate return 
of pure wool-fibre in the manufactured woollen goods, bases his judgment 
as to value upon the amount of non-wool material which he estimates to be 
present ; in addition it has to be borne in mind that it costs a considerable 
sum to remove adherent dirt and blood from the wool at the mill, and 
hence it is important to pay adequate attention to the washing of the wool 
and skin immediately after the removal of the skin from the carcase. 
This washing of the skin must not be confused with the process of 
scouring, which is carried out at the woollen-mill after the arrival of the 
“ slipe ” wool, as it is termed. 
The skin with its wool, after removal from the washing paddle-vats, 
is then placed in some form of hydro-extractor, usually a centrifugal 
machine which throws out the surplus water, leaving the skin and wool 
comparatively free from an excessive amount of adherent moisture. 
In order to remove the wool from the skin a process termed “.depilation 
is employed. Formerly this proces of depilation was carried out (and it 
is even yet in some quarters) by “ sweating ” the skins ; this method is 
probably one of the most ancient forms of depilation, depending as it does 
upon the action of putrefactive bacteria to bring about the loosening of 
the w r ool-fibres from the skin. 
The “ sweating ” process, while being one which is satisfactory as regards 
the wool, has been found to be objectionable on account of the injury which 
it causes to the pelt, or skin. Despite this fact it is still employed in 
some fellmongeries, and consequently some account of the operation is 
justified. 
* The author desires to express his thanks to the New Zealand Refrigerating 
Company (Limited) for permission to publish this article, 
f See “ Literature cited,” p. 164. 
