THE RAISIN INDUSTRY. 13 
_ The following formula has been used for Sultana and Sultanina 
grapes at Fresno: : 
Fifteen pounds of ‘ Greenbank’s 98-per cent lye” are boiled in 100 gallons of 
water. This mixture is for grapes containing 25 per cent of sugar. Should 
their sugar content be less, enough lye is added to remove the bloom and open 
the pores of the skin of the grapes. After dipping, the grapes are spread on 
trays and sulphured for 1 to 14 hours. Observation will show whether it may 
be necessary to vary this formula a trifle to suit conditions of ripeness and 
influence of temperature. The length of time required for dipping is ascer- 
tained by experience, and differs with the strength of the lye, the heat of the 
solution, and the thickness of the skins of the grapes. 
PACKING RAISINS.* 
The raisins as received at the packing house are weighed and the 
loose raisins and those that are to be shipped as dried grapes are 
immediately run through a stemmer and grader (PI. VIII, fig. 1), 
which stems, cleans, and assorts the raisins into three or four dif- 
ferent grades, after which they are packed and shipped to various 
parts of the country, some also being exported. Those producing 
cluster or layer raisins (if they have not already been equalized) are 
first stored in the equalizing rooms (PI. VII, fig. 3). In these rooms 
the sweat boxes, filled with layers of new raisins, are stacked and left 
usually from 10 to 30 days, or long enough for the overdried berries 
to absorb moisture from the underdried ones. This sweating also 
properly softens and toughens the stems, which prevents their break- 
ing and enables them to hold the berries better. In California, 
where the climate is so dry, no first-class pack could be made without 
thus first equalizing the raisins. After having been equalized the 
raisins are taken out, assorted into the different grades, and placed 
in trays holding 5 pounds each (PI. IX, fig. 1). The trays of the 
same grades are then pressed and stacked away in piles ready for 
packing. 
Pressing the raisins so they look well and so none are burst open 
is work requiring experience and good judgment. It takes four 
pressed trays to fill a 20-pound box. The loose raisins that have 
dropped from the cluster through handling before they were equal- 
ized are also graded, the largest, of course, making the choicest pack. 
CLASSES OF RAISINS. 
Previous to the consolidated organization of the packers the three 
best grades of raisins on the stems were known as “ Imperial,” “ De- 
hesia,” and “ Fancy Clusters,” respectively. The California Raisin 
_ Growers’ Association established classification and grades similar to 
« 

1 Department Bulletin No. 235. ‘“ Control of Dried-Fruit Insects in California.” 
