20 CIRCULAR 2 7 8, IT. S. DEPARTMENT OF AGRICULTURE 



range from 36° to 40°, is not satisfactory because of the common 

 occurrence of end rot, a fungus disease, which can develop at low 

 temperatures {118) . Shrinkage of the berries as a result of water loss 

 is also a limiting factor. Further facts that need to be kept in mind 

 are that keeping quality depends to some extent on the maturity of 

 the fruit, that some varieties keep better than others, and that there 

 may be a difference in keeping quality from year to year in crops 

 from the same bog. 



Cranberries for long-time storage are best held "in the chaff" in 

 the picking crates as they come from the field. Thus handled they 

 keep better than if sorted and cleaned previous to storage. 



Cleaned and sorted cranberries can safely be stored at the market 

 for 5 to 8 weeks if held at a temperature of 32° F., but fruit held for 

 a longer time at that temperature is likely to develop a "low-temper- 

 ature break-down." Berries in this condition are "rubbery" when 

 pressed between the fingers, the flesh is permeated with red pigment 

 from the skin, and some of the natural luster has disappeared. Such 

 berries closely resemble those that have been frozen. Fruit held at 

 36° to 40° is less likely to discolor and become rubbery, but if it has 

 been cleaned and sorted it is more likely to suffer from decay than if 

 held at 32°. 



(See4,«J.) 



Dates 



(Temperature, see text; relative humidity, 65 to 75 percent; or 28° F. and no 

 humidity control for cured grades) 



Dates absorb moisture and odors readily from the air. The rate of 

 absorption is much less at temperatures below 32° F. than at those 

 above 32°. Deterioration caused by humidity above 75 percent is 

 slow at storage temperatures below 28°. The dates of commerce are 

 of three grades with respect to storage life — dried, cured, and non- 

 cured. The cured and noncured grades are perishable. A tempera- 

 ture as low as 0° has no deleterious effect upon dates but is actually 

 beneficial to them. 



Dates are of two different types, and fruits of each type are likely 

 to be either dry, cured, or noncured. The cane-sugar type is usually 

 firm, light-colored, and comparatively dry, whereas the invert-sugar 

 type is usually softer, darker colored, and inclined to be slightly sticky 

 or sirupy. 



Deglet Xoor, the most important variety grown in this country, is 

 of the cane-sugar type. Dates of this variety, cured grade, keep well 

 until March at 28° to 32° F. and for a year at 24° to 26° or lower, 

 whereas the noncured grade requires 18° or lower for storage until 

 March and 0° to 10° for a year. In Deglet Noor dates that have be- 

 come overripe or have been held under unfavorable storage conditions 

 the cane sugar is inverted and the dates become soft, sirupy, and 

 darker in color. Such dates are commonly graded as "dark soft." 

 If they can be dried down somewhat, they can be stored at 28° to 32° 

 until Christmas without becoming objectionably dark and sirupy, 

 although a temperature of 0° to 10° will be needed if they are to be 

 stored until March. If such dates are not cured, a temperature of 

 0° to 10° is necessary for even short-time storage (89) . 



