2 BULLETIN 349, U. S. DEPARTMENT OF AGRICULTURE. 
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weather, the earliest picked grapes drying in 10 days and the later 
ones often taking four weeks or more. 
The method of drying is very simple. The bunches are cut from 
the vines and placed in shallow trays 2 feet wide, 3 feet long, and 1 
inch high (Pl. V, figs. 1 and 2), on which the grapes are allowed to 
sun-dry, being turned from time to time by simply placing an empty 
tray upside down on the full one and then turning both over and 
taking off the top tray. After the raisins are dried they are stored 
away until they are packed and prepared for shipment. Some of — 
the larger growers, in order not to run so much risk in drying on 
account of rain, and also to enable them to handle the crop fast © 
enough, have curing houses, where the curing is finished after having 
been partially done outside. 
DIPPING AND SCALDING RAISINS. 
The operation of dipping and scalding is designed to accomplish 
several purposes, namely, to cleanse the fruit, to hasten its drying, 
and to give the dried fruit a lighter color. In dipping and drying, 
the fruit, immediately after being cut from the vines, is either dipped 
in clear water to first rinse it of particles of dust and other foreign 
matter, or it is taken direct to the scalder and immersed in a boiling 
alkaline mixture called “legia” (lye) until the grapes show an 
almost imperceptible cracking of the skin, the operation consuming 
perhaps from one-fourth to one-half of a minute. This dipping 
calls for skill on the part of the operator, the duration of the im- 
mersion depending on the strength and temperature of the mixture 
and the condition of the fruit. Desiccation follows the scalding 
process, which is accomplished on trays (Pl. VU, fig. 1) in the sun, 
the same as undipped raisins cured entirely by solar heat (Pl. VU, 
fig. 2).. On account of the scald they cure rapidly, and the fruit is 
also often of lighter color when cured. The following formula has 
been used at Woodland, Yolo County, for Sultana and Sultanina 
grapes: 
Thirty pounds of English bicarbonate of soda are boiled in 30 gallons of 

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AT oretin’ Recall 
water until dissolved, to which are added 70 gallons of water and approximately ~ 
one teacupful of genuine olive oil. This mixture is for grapes containing 25 
per cent of sugar; should their sugar content be less, more bicarbonate of soda : 
is added. The bicarbonate of soda must be sufficiently strong to remove the ~ 
bloom of the grape and open the pores of the skin to facilitate drying. The 
cup of olive oil added forms a thin film on the surface of the solution. This 
film is preserved while dipping by adding an occasional teaspoonful of oil, the 
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mixture being kept sufficiently warm so that the oil dissolves perfectly and — 
spreads evenly over the surface. Three-fourths of a gallon of olive oil will be 
sufficient to dip 5 tons of grapes in the mixture as given here. When the solu- 
tion gets dirty it is renewed. 
