Contribution from the Bureau of Plant Industry 
WM. A. TAYLOR, Chief 
Washington, D. C. PROFESSIONAL PAPER™ : June 4, 1921 
COMMERCIAL UTILIZATION OF GRAPE POMACE 
AND STEMS FROM THE GRAPE-JUICE INDUS- 
TRY.’ , : 
By FRANK RABAk, Chemical Biologist, and J. H. SHRADER, Chemical Tech- 
nologist, Office of Drug, Poisonous, and Oil Plant Investigations. 
CONTENTS. 
; Fage. Page. 
The conservation of fruit-product Quantity and value of jelly and 
WPSURS sae Soe ce ee See Hee 1 TGS CU Che eee al ace ards md, TES ee eda eh 13 
Accumulation and present. disposal Manufacture of oil from grape 
OMpOTAPOuWwaSsten 2222 Lees ees 2, SECS een are edt cone eae te 15 
Available quantity of grape waste__ 4 | Extracting tannin from the hulls___ 17 
Commercial products obtainable from Quantity, uses, and value of the oil, 
IAM Ch WAST aoe eo ek eS 4 oil cake, and tannin extract from 
a PEA EAS CCC Saws apes ok a ahs See 18. 
Cream of tartar from grape stems_— ” | Gross returns ‘and net profits from 
Preparation of grape pomace for the the undertaking _____ Spee 20 
manufacture of jelly and oil_____ 6 SiopoilinsQate agate ep oa eens esha eau ies MS 92 
Making jelly from grape skins_____ LOM Literature cited] .2= a= a es 23 
THE CONSERVATION OF FRUIT-PRODUCT WASTES. 
OR MANY YEARS the cultivation of grapes for the produc- 
tion of grape juice has been an industry of large and growing 
proportions, and with the increasing popularity of the juice as a 
beverage the industry has received added impetus. In the process 
of preparing the juice for market large quantities of stems and 
pomace result, which at present are practically waste material. 
In several publications of the United States Department of Agri- 
culture (13, 14, 15, 16)? it has been shown that in preparing products 
for market from such fruits as cherries, raisins, peaches, apricots, 
and tomatoes the waste resulting from the various processes is capa- 
1 The writers wish to express their thanks to Mr. J. D. McIntyre, Chemical Labora- 
torian of the Office of Drug, Poisonous, and Oil Plant. Investigations, for valuable assist- 
ance rendered during the course of this investigation. 
2The serial numbers in parentheses refer to ‘‘ Literature cited” at the end of this 
bulletin. 
30842°—21 1 
