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Food Preparation Instructions

Drying foods to about 60 percent ERH (Equilibrium Relative Humidity) will prevent microbial growth on fruits and vegetables. But, certain chemical reactions caused by enzymes within the fruit and vegetables can still cause spoilage, color change, loss of flavor and the loss of nutrients. These enzymes must be inactivated to prevent these reactions from taking place. Blanching Vegetables will inactivate these enzymes. Blanching is done by dipping the vegetables into boiling water or steam for a brief period of time. Blanching fruits is not advised. Blanching will give your fruits a cooked taste and texture due to their high water content. The best way to deactivate the enzymes in fruit and to preserve their color and vitamins A and C is with Sodium bisulfite.

Dehydrating machines are more economical for dehydrating than using your oven. It costs about 9 to 12 times more to dry foods in your oven than in a food dehydrator. You also get the best control in humidity, temperature in optimal drying time. Dehydrating machines have a fan and heating element that circulates hot, dry air to quicken the moisture removal process. They also have a temperature control you can adjust depending on what you are drying. Moving air will evaporate moisture faster than still air and the heat releases the moisture from the food.

Each Food Dehydrator has been manufactured to dry up to a specific quantity of food at one time. You must follow the owners manual included with each machine to determine how much you can dry in your machine. Some of the larger dehydrators can hold up to 8 pounds of fresh fruits and vegetables at one drying time. Before purchasing a dehydrator, look at how many trays it has and how large the trays are. Then decide how many slices of fruits and vegetables you want to dehydrate at one time. Another thing to consider when purchasing a dehydrator is how large the outer dimensions are (height, width and depth), where will you place it and store it.

Food to be dried should be sliced into 1/8 to 1/4 inch thick discs or strips. The thicker the slices the longer it will take to dehydrate. A piece which is twice as thick as another one will take four times longer to dry. It is important that all pieces being dehydrated at the same time be cut to the same thickness. That is when a fruit and vegetable slicer comes in handy. It will slice fruits and vegetables evenly. The pieces of food should be spread evenly on the dehydrator trays in a single thin layer. Food should not over lap or touch each other in a dehydrator. Over lapping will slow that portion down from drying and the foods will not dry evenly. Opening your dehydrator during the drying process will slow drying down. Opening the door will let heat out and possibly moisture in. Now you may have to open it towards the end of the drying time to see if the food is dehydrated to the desired dryness. But do not keep opening it just to see what is going on in there. Also do not keep adding fresh produce to the dehydrator as it is drying. This will increases the drying time and will produce a poor end result. If new food is introduced moisture is also introduced. As you repeatedly use your dehydrator you will learn how long it takes for a specific cut of food to reach your desired dryness. Just keep notes of what you did for future reference.

The optimal drying temperature for both fruits and vegetables is about 140 degrees to 145 degrees F. Lower temperatures are acceptable, but higher temperatures are not recommended. Higher temperatures can dry out the outer surface faster than the inside. If the inside does not dry to a low enough moisture level, the food will be more susceptible to premature spoilage. Drying times on humid or rainy days will be much than dehydrating on days with low humidity.

Vegetables must be dried to about 5 percent water content and fruits to 15 to 20 percent water content. The reason dried fruits are stable at a higher moisture content than dried vegetables is because of the natural sugars and acids in the fruit function as an added preservative. Vegetables must be dried to about 5 percent water content and fruits to 15 to 20 percent water content. The reason dried fruits are stable at a higher moisture content than dried vegetables is because of the natural sugars and acids in the fruit function as an added preservative. To determine if vegetables are dry, remove a piece after a minimum of 6 to 8 hours of drying time. Allow the pieces to cool to room temperature. It is dry if it is brittle or crisp. It should break or shatter when bent or bitten. For the thick, small pieces that you can not bend or bite, hit them with a hammer and they should shatter. To determine if fruit is dried enough, remove a piece from the dehydrator towards the end of the drying period according to your dehydrators owners manual. Cool it to room temperature. It should feel pliable and leathery. There should not be any pockets of moisture.

Dried foods must be stored properly to maintain the low moisture content and to prevent spoilage. Before packing foods, the dried pieces should be allowed to cool for as short amount of time as possible. As soon as it has come to room temperature, place the dried food in plastic bags, glass jars, or vacuum sealed bags. Plastic containers or metal cans with plastic lids are not recommended because moisture can enter through the container. You want to not only keep out air and moisture you want to seal the food up with as little air space as possible.

The shelf life of home dried fruits and vegetables when stored at 60 degrees F is 4 to 6 months in a zip lock or vacuum seal bag. If stored at 70 degrees F, the shelf life will be shorter. To lengthen the storage time seal the dried fruits and vegetables in a vacuum seal bag. Note that every time you open any bag you let in moisture. To store your fruits and vegetables longer, seal the dried product in a vacuum sealer bags. Foods stored in vacuum sealed bags and zip top bags can also be stored in the refrigerator and freezes to extend the foods life as long as the bag is sealed tightly to prevent air and moisture from entering the bag.

Rehydrating dried vegetables is not necessary, but if you soak 1 cup of dried vegetables in 2 cups of water or vegetable broth for 2 hours your cooking time will be significantly shortened. After soaking the dried vegetables for 1 hour, check to see if you should add a little more water. The vegetables should return to their original cut size before dehydrating. If there is any left over water after 2 hours of soaking, use that water or broth in something you are cooking. That liquid will contain some nutrients from the vegetables. Dried fruit can be eaten in its dry state. If you wish to plump up your fruit, either place the fruit is enough boiling water to cover. Remove from burner and let sit for 5 minutes. Drain off the excess water. You may also use this water to cook with just as the vegetable soaking water. Or, place the dried fruit in a steamer basket over boiling water and steam for 3 to 5 minutes.

Refrences:

University of Illinois at Urbana-Champaign, College of Agriculture, Cooperative Extension Service TheCookingInn.com

Copyright by VeggieSensations.com 8/28/2008