22 BULLETIN 952, U. S. DEPARTMENT OF AGRICULTURE. 



erations, thus reducing the cost of equipment and labor charge as 

 well. If only a few of the products are manufactured, the profits 

 would necessarily be reduced, since the cost of preparing the ma- 

 terial would be distributed over a smaller number of products. 



Complete utilization of grape waste for its full market value would 

 be possible only when done at one point, since increased costs would 

 mitigate against the success of the undertaking if attempted at sev- 

 eral points with only a fraction of the total quantity of material 

 available for reduction. 



SUMMARY. 



Since this investigation has shown that the waste which accumu- 

 lates annually in large quantities at the various grape-juice plants 

 can be made to yield a number of commercially valuable products, 

 the utilization of this material should command the serious attention 

 of manufacturers. 



The jDossibilities have been pointed out and attention has been 

 called to the proper and most economical methods for handling the 

 waste. The procedure and methods of treating the stems, seeds, and 

 skins for the production of cream of tartar, oil, oil cake, tannin ex- 

 tract, and jelly are most important from the standpoint of' successful 

 exploitation. 



A careful study of the cost of the various operations involved in 

 handling the waste and in manufacturing the products shows, by 

 comparison with the returns, that profitable utilization is entirely 

 possible. 



It should be understood that all costs and returns, unless other- 

 wise specified, were calculated on prices prevalent during the winter 

 of 1919-20. Therefore fluctuations in prices and costs of freight, 

 labor, machinery, and products must be given due consideration in 

 the interpretation of the returns possible from an undertaking of 

 this character. 



With the growth of the grape- juice industry an increase in the 

 quantity of waste will result. The more urgently, therefore, should 

 be emphasized the necessity for utilizing this waste, both as an 

 adjunct to the mother industry and as a reclamation project of agri- 

 cultural and industrial importance. 



