VEGETABLE AND FRUIT DEHYDRATION 207 



The varieties of spinach commonly grown for use as fresh vege- 

 table are probably satisfactory for drying. Nobel, also known as 

 Giant Thick Leaf, is very productive. The smooth leaves are easily 

 cleaned, and it stands for a long time before going to seed. Long 

 Standing Bloomsdale is the most widely grown savoy-leaved variety. 

 Virginia Savoy and Old Dominion are good varieties for fall plant- 

 ing, since they are hardy, but are not suited for spring planting. 



Spinach is perishable and should be processed as soon as possible 

 after harvest. Cooling quickly to 34° or 35° F. in air at 90 or 95 

 percent relative humidity will help prevent spoilage. Crushed ice 

 applied to the pack will hasten cooling and protect the quality over 

 short periods of unavoidable delay. 



Undue handling or bruising of the leaves of fresh spinach will 

 result in large losses of ascorbic acid. The first step in the prepara- 

 tion is the cutting off of the roots. The loose material is then washed 

 under cold water sprays as it is loaded on the conveyor belts. Next, 

 all damaged and discolored leaves are removed and the stems cut off. 

 Not more than 10 percent of the stem should remain on the spinach. 

 Trimming losses for spinach range from 45 to 65 percent. After 

 sorting and trimming, the leaves are thoroughly washed to remove 

 the remaining sand and dirt. 



Spinach should be blanched, as soon after preparation as possible, 

 in live steam until the catalase system is destroyed (table 21). Care 

 must be taken to see that the leafy material is uniformly loaded in 

 the blancher. If there is a delay between blanching and dehydration, 

 the product should be cooled immediately to 65° or 70° F. by means 

 of water sprays or immersion in cold water. This is essential as a 

 means of preventing discoloration (undesirable brownish color) in 

 the finished product. The delay between blanching and dehydration 

 should not be more than 1 hour. 



Information on dehydration is presented in tables 22 to 25. The 

 leaves are preferably dried whole. Various kinds of greens should 

 not be dried together, nor should they be mixed after they are dried. 

 Because of the limp condition of the blanched leaves, care should be 

 taken to spread the material so that it will not pile up in bunches. 



Government procurement specifications require dehydrated spinach 

 to be packaged in hermetically sealed containers in which the air 

 has been replaced by nitrogen or carbon dioxide gas. Spinach dried 

 to 2 percent moisture content can be packaged in lead-foil-protected 

 cartons if it is stored at safe temperature and for short periods, such 

 as would commonly be possible in domestic use. For longer and 

 more severe storage, such as would be necessary in shipment abroad, 

 gas-packed sealed cans are advisable. In quality tests, unblanched 

 spinach dried to 2 percent moisture content and stored at 90° F. was 

 found to retain its palatability after more than a year. 



For the rehydration test the following procedure is recommended : 

 To one part by weight of dried spinach add six parts of water. Soak 

 for 2 hours and then boil gently for 5 minutes. The drained weight 

 of the rehydrated product should be about three to four times the 

 original weight. Longer soaking will do no harm, but longer boiling 

 will cause loss of vitamins and flavor. The product should be mildly 

 bitter, soft, tender, a uniform dark green, and free from foreign 

 odor. 



