2, BULLETIN 1159, U. S. DEPARTMENT OF AGRICULTURE, 
Ratio of soluble solids to acid.—TYo determine the ratio of solubl 
solids to acid divide the percentage of soluble solids (Brix readin 
corrected according to temperature) by the percentage of acid. 
Example: Percentage of soluble solids, 8.74, divided by 0.9 equals 9.7; i. e. 
the ratio of soluble solids to acid is 9.7 to 1. 
SUMMARY. 
Satsuma oranges in Alabama become edible, palatable, and suit- 
able for food some weeks before they assume a yellow or orange 
color on the tree. 
Normally the picking of Satsuma oranges colored on the tree 
begins about October 15, but frequently, owing to seasonal variations 
in ‘climate, picking is delayed from two to four weeks. 
In certain sections local variations in environment tend to delay 
ripening or coloring. : 
The process of coloring as applied to the conditions in Alabama — 
enables the growers to get their fruit on the market four to six weeks 
sooner than if it were left to color on the trees. ‘ 
This procedure enables the growers to obtain better prices on 
the market and in addition serves to insure the crop against early 
frosts. ; 
Coloring is accomplished by the action of the exhaust gas driven © 
off by a gasoline engine or by the incomplete combustion of kerosene 
ina stove. This gas destroys the green chlorophyll which masks the 
yellow color. 
Satsuma oranges to be colored should meet the requirements of — 
United States Department of Agriculture Food Inspection Decision — : 
182 and contain “ not. less than eight parts of soluble solids to each 3 
part of acid calculated as citric acid without water of erystalli- — 
zation.” F 
Fruit carrying up to 40 per cent natural ripe color will ordinarily Fi 
require four days in the coloring room to develop the full golder — 
yellow color. 
