1 Mar., 1899.] QUEENSLAND AGRICULTURAL JOURNAL. 185 
CHEESE ROOMS. 
If it is desired, as should be the case, to produce the best results with the 
minimum of extra trouble, a cheese-ripening room specially constructed will go 
a long way to this end. The room must be so arranged or managed that 
damp, cold, and excessive heat are excluded, thoroughly well ventilated so that 
the temperature can be controlled and kept within certain limits. The floor, 
and any shelves or stands which may be fitted up, should be of some hard close- 
lying wood. Artificial means of raising the temperature of the room, which 
ure fitted up in most—one might say all—dairies of modern construction, are 
preferably hot-water pipes, the actual means of heating, z.¢., the stove, being 
outside the room. Cellars or underground rooms, if properly built, are much 
easier kept under control as regards the regulation of temperature, which we 
pial presently see is one of the important factors governing the ripening of 
cheese. 
THE PROCESS OF CHANGE. 
Various physical and chemical changes take place before the green curd 
becomes a mature cheese, and although the composition of the cheese depends 
to a very great extent on the cheese-making properties of the milk from which 
it is manufactured, yet all the different kinds of cheese made from whole milk 
start at the same thing, and their special characters owe their development 
mainly to the after treatment during the ripening period. 
The ripening process is really one of gradual decay, in which the con- 
stituents of the cheese alter their nature by the action upon them of certain 
organisms, classed under the names of “moulds” and “bacteria,” and also to the 
unorganised ferments produced by the latter, and termed “ enzymes.” 
The nitrogenous constituents of curd are gradually transformed into a 
soluble condition, becoming more mellow, and melting as ripening proceeds ; 
the reason why fresh cheese is so solid and unpalatable is because the casein of 
the curd is insoluble. : 
In some cheeses the “ butter-fat” begins to decay, giving rise to certain 
fatty acids, &c., which serve to play their part in the ultimate nature of the 
cheese ; but in many cases, where, as the cheese ripens, fat seems to be produced, 
really it has only accumulated owing to loss of casein (by solubility), water, 
&e. <A certain amount of fat is usually lost, but not from chemical causes or 
reactions. This point will be considered later on. 
Milk sugar, which is present in fresh cheese in small quantities, is not 
found in ripened cheese; it has been decomposed into such bodies as lactic 
acid, and possibly butyric acid. 
During ripening a certain amount of gas is produced, chiefly carbonic acid 
gas, and it in excessive quantity a “ puffy’? cheese is the result. Amongst 
other products of decomposition, alcohol, carbonate of ammonia, and such 
fermenting substances as leucin and tyrosin are foand. The percentage of 
water becomes less, and the whole cheese loses in weight. ‘The general process 
seems to conduct itself in a similar way to that of digestion by the digestive 
fluids in the stomach and alimentary canal of an animal, 
CHANGE IN TEXTURE. 
The transformation of the hard elastic curd into a soft buttery cheese is a 
process which must go on under ordinary conditions; that is to say, the bacteria 
working this change, having originated in the milk, are enabled to effect this _ 
transformation even under the most unfavourable conditions. It is the flavour 
and mellowness of the cheese which suffers under a bad system of management, 
for the change in texture is not entirely coincident with the acquirement of a 
{ull ripe taste; indeed, the actual texture of a cheese may be all that is desired, 
and yet a further period of time is necessary for the development of the peculiar 
flavour. 
