34 
POPULAR SCIENCE REVIEW. 
WHAT IS WINE? 
BY A. Duplin, Ph.D., 
Lecturer on Chemistry, Westminster Hospital. 
I N a former communication we have seen how, in the course 
of fermentation and subsequent maturing, the compara- 
tively speaking simply constituted must is changed into the 
highly complex mixture wine. We will now consider some- 
what more fully the quantitative relation of some of its most 
important constituents. Before doing so, however, it may be 
well once more to recall to mind the various substances hitherto 
detected in wine, and to contrast them, in a tabular form, with 
those found in the must. 
Must contains 
water 
ST7'}»*» «•/. 
malic acid 
tartaric „ 
racemic „ 
albumenoid substance 
vegetable mucus 
essential oils 
extractives 
mineral substances 
tannin 1 f rom ^ g^g 
colouring matter f and kernels 
fatty oil J 
Wine contains 
water 
grape sugar) 
fruit „ [0-0to6»/ o 
ethylic alcohol 5 to 22% 
propylic „ 
butylic „ 
amylic „ 
etc. etc. 
malic acid 
tartaric 
if 
racemic „ 
acetic 
.0 3 to 0-8 
succinic,, r 
formic „ 
propionic,, 
butyric „ 
etc. etc. ^ 
ethers of foregoing alcohols and acids 
glycerine 
aldehyd 
carbonic acid 
ammonia 
trimethylamin 
