Freeze Drying

Freeze-Drying Or Lyophilisation Or Cryodessication

graph

Freeze-Drying is a process of sublimation where water molecules in a solid phase are directly converted to vapor phase.

It’s a dehydration process of foods under vacuum so the moisture content changes directly from a solid to a gaseous form without having to undergo the intermediate liquid state through sublimation. During and after the process original size, shape, colour and natural ingredients are retained. Speciality of this process is removal of interstitial cell water with minimum rupture to cells. Thus all nutrients are kept as such even after processing.

The process is used for drying and preserving a number of food products, including RTE, RTS, vegetables, fruits, and instant coffee products.

Depending on the product and the packaging environment, freeze dried foods are shelf-stable at room temperature for up to twenty-five years or more, if canned, and between 6 months to 3 years if stored in a poly-bag container.

The main determinant of degradation is the amount and type of fat content and the degree to which oxygen is kept away from the product.

The Benefits of Freeze-Drying

There are several benefits to freeze-dried foods over dehydrating:

  • Products become very light due to removal of water.
  • Bulk amount of products can be transported easily and efficiently.
  • Nutritional quality, colour, taste, shape and size is retained.
  • Stored at room temperature without refrigeration.
  • Preserved for months or years.
  • Rehydrated very quickly and uniformly.
  • Spoilage due to microorganisms is prohibited.

Freeze Drying Fruits and Vegetables

Freeze-drying or lyophilisation or cryodessication is a kind of preservation technology by which the material is cooled down to its eutectic temperature or glass transition temperature. Its commonly called as sublimation in which water molecules in a solid phase are directly converted to vapor phase. It’s a type of vacuum dehydration process for preservation of heat sensitive and high value products and ingredients.

The freeze drying of fruits and vegetables is emerging and high value-added technology. Its bottlenecks has been rectified over the period of time and it's now time and energy saving methodology. The parameters of the freeze-drying process have decisive impact on the quality of freeze-dried food.

Range of freeze dried products are:

Fruits and Vegetables:

  • Apple
  • Guava
  • Sapota
  • Strawberry
  • Mango
  • Jackfruit
  • Okra
  • Spinach
  • And Many More...

Herbs and Spices:

  • Curry Leaves
  • Ginger
  • Garlic
  • Chilli
  • And Many More...

RTE/RTC/RTS:

  • Pav Bhaji
  • Biryani
  • Curries
  • And Many More...


This is a representative list of products. The products can be customized and tailored as per market demand and customer needs.

Applications

Freeze-dried foods are high value-added products, regarded as high-quality food, convenience food, leisure food. Those products are exported as vegetables and fruits, or in travelling, exploration, navigation and so on.

Freeze-dried foods are used by astronauts, campers, backpackers, food manufacturers and the military. Those products can also be used for domestic purpose like fruit pieces found in some cereals and astronaut ice cream found in gift shops. Entire meals can be freeze-dried, as almost all foods can be freeze-dried like biryani, pav bhaji, curries etc.