96 



by the very rapid increase of the yeast plants, as a result of which a 

 sort of boiling of the liquid is produced, much carbonic acid gas is 

 liberated, and the minute bubbles of this gas rise through the liquid 

 and escape with a hissing sound, often alluded to as the ''singing of 

 the cider." This development of the yeast is likely to be altogether 

 too tumultuous if the temperature is high; hence the importance of 

 regulating the temperature. If the characteristic fermentation super- 

 venes within twent} r -four to forty-eight hours, it is a sign that proper 

 progress is being made. The liquid at once becomes turbid and much 

 disturbed, and small particles of vegetable matter rise to the surface, 

 accompanied by more or less viscid mucilaginous material, all of 

 which is really borne upward by the escaping gas. At first this sur- 

 face material is light and frothy, but should assume more and more 

 the character of a well-defined crust or covering, the u chapeau" so 

 often mentioned by the French. This, however, is not considered 

 important by some. The English makers seem to be pleased if the 

 head forms well in their "keeves," because they can then skim it off 

 and be rid of so much of the lees, but if it does not form they make 

 no effort to secure its formation. On the other hand, the French 

 maker, if the head or "cbapeau" does not form, at once concludes 

 that his must is sick, and takes steps to set it right. It may be that 

 unfavorable temperature is the sole trouble, or at other times there 

 really is a lack of proper yeast organisms in the must. 



No one appears to explain this matter of the formation of top lees or 

 "head" on the basis of observed facts, nor does it appear that any suffi- 

 ciently critical chemical study has been made of the subject. From 

 all the observations made this seems to be a very important feature of 

 the first fermentation, and it should be thorough^ studied. Some of 

 the remedies proposed by the manufacturers for application in case 

 the head does not form properly, appear not to deserve serious con- 

 sideration, namely, the addition of small quantities of ashes boiled in 

 cider, or of clay. The only result of such substances would be to 

 neutralize the acids, which, as a rule, would prove quite injurious to 

 the growth of the yeasts. In fact, the writer has fully proven that 

 neutralizing the acids checks the normal fermentation very decidedly. 

 It is also proposed by some makers to add a portion of the head from a 

 properly fermenting cask; and this has some element of sound sense in 

 it, because one would thus sow the must with vigorous yeasts, but he 

 would also sow it with many other organisms, probably some unde- 

 sirable ones. 



The German makers care little or nothing about the formation of 

 the head or top lees, for reasons already explained, but they watch 

 carefully to see that the must comes into strong fermentation, and if 

 this does not occur at the proper time they sow strong yeast cultures 

 into the must, correct the temperature if necessary, and, as a yeast 



