home  Introduction History Technology Agro Associations Agro Scenario Career Opportunities

 Other Agro Products
Natural Honey
Sugar
Soya Meals
Jaggery
Flour
Tobacco Products
Brewed Liquor
Natural Dyes and Pigments
Potpourri
Baby Food
Soup
Dehydrated vegetables
Dehydrated fruits
Vinegar
 
 
 
 

 
Dehydrated Vegetables

Canned food, stored preservatives and well packed vegetables have stormed our kitchens so much that we hardly feel the seasonal variance of the vegetables and fruits. It all seems so simple and nutrition being on the top of our minds, preserved and dehydrated vegetables seem to provide the best solutions.

The progression of time, technology and necessity have encouraged human beings to invent and find solutions to the ever sustaining problems. One of the major reasons for our survival, food has also provoked us to think of various methods to preserve and store it in different productive manners.

 

The seasonal and perishable vegetables are a challenge to normal storage and thus dehydration is one of the most convenient and appropriate methods to preserve them in a dry form and thus making them available throughout the year in hygienic conditions at reasonably priced tags.

We should eat to live and not live to eat. This fact is but a golden truth of life, as hunger is the most feared and dreaded situation of our lives. As the human mind thought of techniques to store food for emergency needs or later times, various techniques flooded his creative and innovative mind. One of the many techniques involved in preservation of food is dehydration of the food items.

 

What is dehydration?
Most of the vegetables generally contain more than 75% water and that leads to their spoilage in shorter duration if not stored properly. Moreover even proper storage also does not come handy if the vegetables are not properly dehydrated.

Dehydration of the vegetables enables them to restore the nutrients and let loose of the fats thus transforming the all time favorite vegetables into nourishing , revitalizing and health conscious food.

The oldest food preservation technique has been practiced since ages. Even in the older times, ancient civilizations incorporated various methods of drying the vegetables and fruits top store and preserve enough food for the future usage.
 
Solar radiations have been the ultimate source of hot and blazing fire that burnt the water quotient inside the vegetables and making them last for a year or so. Stoves, gases and other heating devices were brought into use until food dehydrators were introduced. Today, we are well outfitted with the latest and most sophisticated techniques of food dehydration listed below:
  • Traditional Sun Drying
  • Solar Dryers
  • Mechanical Dryers
  • Vacuum freeze drying
  • Vacuum drying
  • Osmotic dehydration
  • Dehydration through explosion puffing
  • Microwave based technique
  • Hot air dehydration processing
  • Scientific cultivation of vegetables, etc.

Disadvantages of Sun-Drying

  • Traditional sun-drying of the vegetables is highly time consuming.
  • Open drying provides less hygienic conditions for soaking the vegetables in the sun.
  • Moreover sun drying is totally dependent on climate conditions and thus can not be processed any day.
  • Therefore, new and better methods have been evolved to dehydrate vegetables through osmotic dehydration and vacuum drying.
  • The most suitable method to preserve the hygiene, quality, flavor and nutrients of the vegetables as sun-drying also absorbs the vitamins present in the green vegetables.
 

The dehydrating process involves following steps as well:

  • Grading and sorting of the vegetable
  • Proper washing
  • Peeling/trimming and size reduction
  • Blanching
  • Chemical treatment
  • Dehydration and packaging in suitable air tight containers and jars.

The other equipment needed to enforce the entire process are cabinet or tray drier, stainless steel vessels, perforated baskets, vegetable cutter, peelers, slicers and handling vessels, etc.

How is the Osmotic Dehydration Carried on?
The normal and most popular dehydration process compiles of three prominent steps as following:

Osmotic Dehydration: It is a simple initiating process in which the vegetables are subjected to the osmotic treatment by dipping them into an aqueous solution of sugar under specific required conditions. This leads the water of the vegetables to migrate into the sugar solution thus depriving the vegetables of their water quotient. This step involves the maximum dehydration.

Vacuum/Air Drying: The remaining water is lost through this process as it inevitably the the cutting edge method to dry up the remaining water in less than 6 hours. This step further carries on to the final level of packaging.

Packaging: The final drying through vacuum or air enables the vegetables to be wrapped up in packages to be marketed to the consumers. The safe and hygienic packaging enables the free supply of nutritious and healthy vegetables in all seasons irrespective of their availability otherwise.

Benefits of Vegetable Dehydration

  • Water dehydration leads to the loss of water in the vegetables and due to absence of water food spoilers like bacteria, fungi and molds are unable to grow on the food. Due to this the food remains safe and healthy.
  • Dehydrated vegetables retains more of their nutrients than their other alternative methods of preservation such as freezing and canning.
  • It turns the vegetables to be stored properly due to their light weight, powdered or thin structured texture, increase in volume and are well flavored.
  • Various vegetables like carrot, mushroom and so on are used as flavor to different sauces and condiments and can also be used as ingredient to numerous recipes.
  • The premium osmotic dehydration techniques enhances the storage of the vegetables for a longer duration and at the same time also preserves flavor, nutritional characteristics and prevents microbial spoilage.
  • Due to dehydration, transportation of the bulk vegetables also becomes easy and a variety of seasonal vegetables can be made available trough out the year.
  • The dehydrated vegetables are further used to prepare a variety of confectioneries and other recipes. Dehydrated vegetable soups are one of the most prominent example of dehydrated vegetables.
  • The intermediary step of dehydration that brings the raw vegetables to be supplied all over the world despite of their native lands and seasonal diversities. It not only helps in the hygienic retailing of raw vegetables but also helps in there safe supply to various regions.
  • Dehydration makes the conventional food and pharmaceutical industries possible and profitable as well. Floral products, herbs and other green vegetables when air dried become reasonable and easy to handle.
  • It usually takes green vegetables about 6-16 hours to dry and rest of the time can be utilized in packaging.
  • A prolonged life devoid of spoilage and other damages is ensured by the dehydration of the vegetables. Most of the products last even for five to seven years.
  • Health experts firmly believe that dehydration is a safe and hygienic method to preserve nutritional value of the vegetables and it also ensures availability of demanded vegetables throughout the year.

Dehydration of Onions

  • The onions to be dehydrated are different from the ones usually grown to be used afresh. These special onions possess greater solid content and are endowed with pungent flavor and higher nutritional value.
  • firstly the 4% to 5% of the water is removed from the onion followed by milling or separating to specific particle sizes.
  • Before dehydration, the onion is cleaned and peeled well. then the tops and roots are removed and the materials washed and sliced. Cleaned & sliced onions are subjected to temperature, air flow & retention stages. Scientific removal of the water through osmotic dehydration is carried on followed by vacuum drying and finally the dried onions are packaged in air tight containers and is preserved for future usage.
  • In the similar manner the following vegetables are also dehydrated and later used for prolonged periods.

Carrot, Potato, Cucumber, Onion (Shallot), Spinach, Mushroom, Asparagus, Turnip, Tomato, Broccoli, Bell Pepper, Green Chilly, Cabbage, Cauliflower, Eggplant, Peas, Sweet Pepper, Zucchini, Bottle Gourd, Sponge Gourd Bitter Gourd, Mushroom, etc.

Ready to cook and nutritious to relish, dried vegetables or dehydrated vegetables serve to be the best solution to preservation methods.